Research Article |
Corresponding author: Sonali Garg ( sgarg.du@gmail.com ) Academic editor: Raffael Ernst
© 2022 Sonali Garg, Sivaperuman Chandrakasan, G. Gokulakrishnan, C. Gopika, Indraneil Das, S. D. Biju.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Garg S, Chandrakasan S, Gokulakrishnan G, Gopika C, Das I, Biju SD (2022) The curious case of Charles Darwin’s frog, Rana charlesdarwini Das, 1998: Phylogenetic position and generic placement, with taxonomic insights on other minervaryan frogs (Dicroglossidae: Minervarya) in the Andaman and Nicobar Archipelago. Vertebrate Zoology 72: 169-199. https://doi.org/10.3897/vz.72.e79496
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Since the description of Charles Darwin’s frog as Rana charlesdarwini in 1998, its generic placement has been a taxonomic enigma. Subsequent studies first transferred this species to the dicroglossid genus Limnonectes, and then considered it as a ceratobatrachid of the genus Ingerana, which has since been moved to the family Dicroglossidae. However, recent works have doubted this generic placement and also suggested the possibility of its sister relationship with the genus Liurana, within Ceratobatrachidae. Nonetheless, there have been no detailed investigations to ascertain the generic placement of this taxon by confirming its phylogenetic position or using integrative taxonomic approaches. Here, we provide the first molecular assessment of Ingerana charlesdarwini based on mitochondrial and nuclear DNA and reveal that it is nested in the dicroglossid genus Minervarya. A member of the Minervarya andamanensis species group, Minervarya charlesdarwini comb. nov. is sister taxon to M. andamanensis and shows relatively shallow genetic distances (2.8–3.6%) in the 16S gene. Both species are widely distributed, occur sympatrically, and exhibit high morphological variations, leading to long-standing confusions with other dicroglossid frogs reported from the region. Our combined morphological and molecular studies on dicroglossid frogs sampled across the known ranges of these species suggest that reports of Limnonectes doriae (Boulenger, 1887) and L. hascheanus (Stoliczka, 1870) from the Andamans are misidentifications of the former two, pointing to the absence of genus Limnonectes from the Andaman Islands. Our study also reveals the novel record of Minervarya agricola from the Andamans, a species that appears to have been confused with Fejervarya limnocharis and Minervarya keralensis in the literature and misidentified museum specimens, and is found to be widely distributed across these islands. We further find another congener from the Nicobar group of Islands, M. nicobariensis, to be closely related to M. charlesdarwini. Similar to the case of Andaman dicroglossids, our work emphasises on the need for further studies to ascertain the taxonomic identities and generic placement of Minervarya and Limnonectes species reported from the Nicobars.
Amphibia, Ingerana, integrative taxonomy, island biogeography, Limnonectes, sympatric species
The Andaman and Nicobar Archipelago are home to about 21 species of amphibians, although knowledge on the fauna of these islands remains incomplete (
A classic case is that of Charles Darwin’s frog, originally described in the family Ranidae as Rana charlesdarwini. Ever since its description, this species has had an uncertain genus as well as family level placement (
The genus Ingerana, with currently four recognised species, is reported primarily from mainland regions of South and South-east Asia spanning across north-east India, southern China, Bhutan, Bangladesh, Myanmar, Thailand and the adjoining Peninsular Malaysia (
The genus Minervarya is recognised as a predominantly South Asian radiation, whereas Limnonectes members are largely restricted to South-east and East Asia (
Hence, in an attempt to resolve the curious case of Ingerana charlesdarwini, we studied multiple closely related and possibly confused Andaman species (Ingerana charlesdarwini, Limnonectes doriae, L. hascheanus, and Minervarya andamanensis) to address some persisting questions due to their complex taxonomic identities and unresolved systematic relationships. We extensively sampled these taxa, based on their apparent identities as understood in the literature, and provide the first integrative molecular and morphological assessment for these species from the Andaman Islands. Our study further investigates the identity of Fejervarya ‘limnocharis’ reported from Andamans and also looks into the systematic relationships of another closely related minervaryan frog, Minervarya nicobariensis, from the Nicobar group of islands.
Sampling of various species of dicroglossid frogs was carried out across the Andaman and Nicobar Archipelago (Tables
Genomic DNA was extracted from 15 samples using the Qiagen DNeasy blood and tissue kit (Qiagen, Valencia, CA, USA). From all the extracted samples, a ~540 bp fragment of the mitochondrial 16S rRNA gene was PCR-amplified using primers from
Bayesian inference (BI) and Maximum Likelihood (ML) analyses were performed with a concatenated character matrix of 2,101 nucleotides for 69 taxa (Table
S.N | Taxa | Collection Locality | Voucher No. | Accession Number | Reference | |||
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Minervarya andamanensis group | 16S | 12S | TYR | RAG1 | ||||
1 | M. andamanensis | India: Andaman Island | n.a. | AB488899 | AB488876 | AB489015 | AB488951 |
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2 | M. andamanensis | India: South Andaman: Mt. Harriet National Park | SDBDU 2019.3951 | ON009955 | n.a. | n.a. | n.a. | Present study |
3 | M. andamanensis | India: South Andaman: Mt. Harriet National Park | SDBDU 2019.3956 | ON009956 | n.a. | n.a. | n.a. | Present study |
4 | M. andamanensis | India: South Andaman: Chidiya Taapu | SDBDU 2019.3964 | ON009957 | n.a. | n.a. | n.a. | Present study |
5 | M. andamanensis | India: South Andaman: Chidiya Taapu | SDBDU 2019.3978 | ON009958 | n.a. | n.a. | n.a. | Present study |
6 | M. andamanensis | India: South Andaman: Munda Pahad | SDBDU 2019.3992 | ON009959 | n.a. | n.a. | n.a. | Present study |
7 | M. andamanensis | India: South Andaman: Chidiya Taapu | SDBDU 2019.3996 | ON009960 | n.a. | n.a. | n.a. | Present study |
8 | M. andamanensis | India: Little Andaman | SDBDU 2019.4011 | ON009961 | n.a. | n.a. | n.a. | Present study |
9 | M. andamanensis | India: South Andaman: Sippi Ghat | SDBDU 2019.4028 | ON009962 | n.a. | n.a. | n.a. | Present study |
10 | M. charlesdarwini | India: South Andaman: Mt. Harriet National Park | SDBDU 2019.3945 | ON009963 | ON009953 | ON010541 | ON010543 | Present study |
11 | M. charlesdarwini | India: South Andaman: Mt. Harriet National Park | SDBDU 2019.3947 | ON009964 | ON009954 | ON010542 | ON010544 | Present study |
12 | M. charlesdarwini | India: South Andaman: Mt. Harriet National Park | SDBDU 2019.3952 | ON009965 | n.a. | n.a. | n.a. | Present study |
13 | M. charlesdarwini | India: South Andaman: Mt. Harriet National Park | SDBDU 2019.3954 | ON009966 | n.a. | n.a. | n.a. | Present study |
14 | M. muangkanensis | Thailand: Pilok | IABHU 18145/18156/18157 | AB277300 | n.a. | AB277352 | AB488956 | Kotaki et al. 2008, |
15 | M. muangkanensis | Thailand: Kanchanaburi, Thong Pha Phum | KIZ 024627 | MF166918 | n.a. | n.a. | n.a. |
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16 | M. muangkanensis | Myanmar: Bago, Dawei | USNM:Herp:587076 | MG935778 | n.a. | n.a. | n.a. | Mulcahy et al. 2018 |
17 | M. muangkanensis | Myanmar: Bago, Dawei | USNM:Herp:587073 | MG935779 | n.a. | n.a. | n.a. | Mulcahy et al. 2018 |
18 | M. muangkanensis | Myanmar: Tanintharyi, Yeybu village | USNM:Herp:586873 | MG935780 | n.a. | n.a. | n.a. | Mulcahy et al. 2018 |
19 | M. muangkanensis | Myanmar: Tanintharyi, Yeybu village | USNM:Herp:586874 | MG935781 | n.a. | n.a. | n.a. | Mulcahy et al. 2018 |
20 | M. muangkanensis | Myanmar: Tanintharyi, Yeybu village | USNM:Herp:586875 | MG935782 | n.a. | n.a. | n.a. | Mulcahy et al. 2018 |
21 | M. muangkanensis | Myanmar: Tanintharyi, Yeybu village | USNM:Herp:586876 | MG935783 | n.a. | n.a. | n.a. | Mulcahy et al. 2018 |
22 | M. muangkanensis | Myanmar: Tanintharyi, Yeybu village | USNM:Herp:586878 | MG935784 | n.a. | n.a. | n.a. | Mulcahy et al. 2018 |
23 | M. muangkanensis | Myanmar: Tanintharyi, Yeybu village | USNM:Herp:586879 | MG935785 | n.a. | n.a. | n.a. | Mulcahy et al. 2018 |
24 | M. muangkanensis | Myanmar: Ayeyarwady, near Mwe Hauk village | CAS 208016 | MK621439 | n.a. | n.a. | n.a. |
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25 | M. muangkanensis | Myanmar: Ayeyarwady, near Mwe Hauk village | CAS 208033 | MK621440 | n.a. | n.a. | n.a. |
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26 | M. muangkanensis | Myanmar: Ayeyarwady, near Kyanigan | SMF 103782 | MK621441 | n.a. | n.a. | n.a. |
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27 | M. muangkanensis | Myanmar: Ayeyarwady, Kan Ywa to Negwesaung | SMF 103787 | MK621442 | n.a. | n.a. | n.a. |
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28 | M. muangkanensis | Myanmar: Ayeyarwady, Kan Ywa to Negwesaung | SMF 103788 | MK621443 | n.a. | n.a. | n.a. |
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29 | M. muangkanensis | Myanmar: Ayeyarwady, Kan Ywa to Negwesaung | SMF 103790 | MK621444 | n.a. | n.a. | n.a. |
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30 | M. muangkanensis | Myanmar: Rakhaing, Ngapali, Dam Lake | SMF 104873 | MK621445 | n.a. | n.a. | n.a. |
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31 | M. muangkanensis | Myanmar: Ayeyarwady, Kan Ywa to Negwesaung | SMF 105012 | MK621446 | n.a. | n.a. | n.a. |
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32 | M. muangkanensis | Myanmar: Ayeyarwady, Kan Ywa to Negwesaung | SMF 105013 | MK621447 | n.a. | n.a. | n.a. |
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Minervarya agricola group | ||||||||
33 | M. agricola | India: Karnataka: Mudigere | BNHS 4651 | AB488895 | AB488872 | AB489011 | AB488947 |
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34 | M. agricola | India: South Andaman: Chidiya Taapu | SDBDU 2019.3986 | ON009967 | n.a. | n.a. | n.a. | Present study |
35 | M. agricola | India: South Andaman: Sippi Ghat | SDBDU 2019.4027 | ON009968 | n.a. | n.a. | n.a. | Present study |
36 | M. agricola | India: Middle Andaman: Rangat | SDBDU 2019.4054 | ON009969 | n.a. | n.a. | n.a. | Present study |
37 | M. asmati | India: Assam | n.a. | AB488900 | AB488877 | AB489016 | AB488952 |
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38 | M. chiangmaiensis | Thailand: Chiang Mai: Omkoi | KIZ024057 | KX834135 | n.a. | n.a. | n.a. | Suwannapoom et al. 2016 |
39 | M. teraiensis | Nepal: Britamod: Jhapa | CDZMTU356 | MT983106 | n.a. | n.a. | n.a. |
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Minervarya greenii group | ||||||||
40 | M. greenii | Sri Lanka: Hakgala | MNHN 2000.617 | AB488891 | AB488868 | AB489008 | AB488944 |
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41 | M. kirtisinghei | Sri Lanka: Hakgala | MNHN 2000.620 | AB488890 | AB488867 | AB489007 | AB488943 |
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Minervarya mysorensis group | ||||||||
42 | M. brevipalmata | India: Kerala: Kadalar | SDBDU 2011.1048 | MZ156230 | n.a. | n.a. | n.a. |
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43 | M. goemchi | India: Goa: Surla | ZSI/WRC/A/2017 | MG800343 | n.a. | n.a. | n.a. | Dinesh et al. 2018 |
44 | M. mysorensis | India: Karnataka: Kudremukh | BNHS 4653 / 4654 | AB488898 | AB488875 | AB489014 | AB488950 |
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Minervarya nilagirica group | ||||||||
45 | M. keralensis | India | WII: 3263 | JX573181 | JX573190 | n.a. | n.a. | Raj et al. 2018 |
46 | M. nilagirica | India: Madikeri | BNHS 4646 | AB488896 | AB488873 | AB489012 | AB488948 |
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47 | M. kalinga | India: Odisha: Barbara Reserve Forest | SDBDU 2015.3108 | MZ156316 | n.a. | n.a. | n.a. |
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Minervarya rufescens group | ||||||||
48 | M. cepfi | India: Maharashtra: Amboli | ZSI/WGRC/V/A/938 | KY447308 | n.a. | n.a. | KY820753 |
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49 | M. kadar | India: Kerala: Thavalakuzhipara | ZSI/WGRC/V/A/940 | KY447312 | n.a. | n.a. | KY820754 |
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50 | M. manoharani | India: Kerala: Chathankod-Bonnacad | ZSI/WGRC/V/A/945 | KY447313 | n.a. | n.a. | KY820757 |
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51 | M. neilcoxi | India: Kerala: Parambikulam | ZSI/WGRC/V/A/951 | KY447318 | n.a. | n.a. | KY820759 |
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52 | M. rufescens | India: Padil: Mangalore | RBRL 040716-1 or 39-16-Jul-2004 | AB530602 | AB488874 | AB489013 | AB488949 | Hasan et al. 2014; |
53 | M. marathi | India: Maharashtra: Pune, Bhamburde | n.a. | MH370483 | n.a. | MH370484 | n.a. | Phuge et al. 2019 |
Minervarya sahyadris group | ||||||||
54 | M. sahyadris | India: Karnataka: Mangalore | SDBDU 2015.3046 | MZ156082 | n.a. | n.a. | n.a. |
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55 | M. gomantaki | India: Codal village | ZSI/WGRC/V/A/867 | KR781085 | n.a. | KT004440 | n.a. |
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56 | M. krishnan | India: Karnataka: Jog Falls | SDBDU 2003.40156 | MZ156093 | n.a. | n.a. | n.a. |
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Minervarya syhadrensis group | ||||||||
57 | M. pentali | India: Kerala: Nedumbaserry | BNHS 6116 | MZ156229 | n.a. | n.a. | n.a. |
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58 | M. nepalensis | Nepal: Chitwan | n.a. | AB488889 | AB488866 | AB500268 | AB500225 |
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59 | M. syhadrensis | India: Karnataka: Mudigere | BNHS 5060 | AB488894 | AB488871 | AB489010 | AB488946 |
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Outgroups | ||||||||
60 | F. limnocharis | Indonesia: Bogor | IABHU 18002 | AB277302 | AB277286 | AB277354 | AB488953 | Kotaki et al. 2008, |
61 | F. orissaensis | India: Odisha | KU 197186 | AB277304 | AB277288 | AB277356 | AB500222 | Kotaki et al. 2008, |
62 | S. dobsonii | India: Bajipe | n.a. | AB277305 | AB277290 | AB277357 | AB488959 | Kotaki et al. 2008, |
63 | S. pluvialis | Sri Lanka | VUB0182 | AF249042 | AF249014 | AF249173 | DQ347214 |
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64 | E. cyanophlyctis | India | VUB0039 | AF249053 | AF249015 | AF249174 | DQ347205 |
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65 | E. hexadactylus | India: Mudigere | n.a. | AB272608 | AB273176 | n.a. | n.a. | Alam et al. 2008 |
66 | H. crassus | Sri Lanka | VUB0107 | AF249044 | AF249013 | AF249172 | DQ347211 |
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67 | H. tigerinus | India: Mangalore | n.a. | AB488902 | n.a. | AB277358 | AB488958 | Kotaki et al. 2008, |
68 | N. ceylonensis | Sri Lanka | VUB0172 | AF249047 | AF249016 | AF249175 | AY948917 |
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69 | L. laticeps | Malaysia: Kuala Lumpur | n.a. | AB277306 | n.a. | AB277359 | AB488960 | Kotaki et al. 2008, |
A species delimitation analysis was performed using the multi-gene ML phylogram as input by Bayesian implementation of the Poisson Tree Processor (PTP) method (
We morphologically examined our new collections and compared them with the available type specimens, original descriptions, other topotypic specimens or general collections of all the dicroglossid frogs known to occur in the Andaman and Nicobar Archipelago. Sex and maturity were determined by the presence of secondary sexual characters (such as nuptial pads and vocal sacs in males) or examination of gonads through a small lateral or ventral incision. Only adult (sexually mature) individuals were used for morphometric studies. The following measurements were taken to the nearest 0.1 mm using digital slide-calipers with the aid of a stereomicroscope, following measurements and associated terminologies of
Abbreviations. Museum acronyms and other frequently used abbreviations are as follows: ZSI (Zoological Survey of India); ZSIC (Zoological Survey of India, Kolkata); ZSI/ANRC (Zoological Survey of India, Andaman and Nicobar Regional Centre, Port Blair); ZSI/SRS (Zoological Survey of India, South Regional Station, Chennai); NHM (Natural History Museum, London), formerly BMNH (British Museum [Natural History], London); Systematics Lab, University of Delhi (SDBDU).
ZooBank registration. This published work and the nomenclatural acts it contains have been registered in ZooBank, the online registration system for the International Commission on Zoological Nomenclature (ICZN). The ZooBank LSID (Life Science Identifier) for this publication is urn:lsid:zoobank.org:pub:2780E8F9-1ABF-4708-898A-B14447591063. The LSID and associated information can be resolved through any standard web browser by appending the LSID to the prefix http://zoobank.org.
Our phylogenetic study found ‘Ingerana’ charlesdarwini to be deeply nested within the genus Minervarya (Fig.
Phylogenetic position and genetic structure of species in the Minervarya andamanensis species group. A. Maximum likelihood phylogram based on a multi-gene dataset (2,101 bp of mitochondrial and nuclear DNA), depicting the phylogenetic position of Minervarya charlesdarwini comb. nov. in the genus Minervarya and relationships among three members of the M. andamanensis species group. Voucher numbers at terminal nodes are referenced in Table
Within the focal Minervarya andamanensis species group, the multi-loci species delimitation analysis recovered all the three recognised species as distinct (Fig.
Minervarya charlesdarwini, M. andamanensis, M. muangkanensis, and M. nicobariensis.
This group can be distinguished from other minervaryan groups by the following suite of characters (revised after
Furthermore, Minervarya charlesdarwini, M. andamanensis and M. nicobariensis are placed in the genus due to the following suite of characters: omosternum unforked; vomerine ridge with weakly developed teeth; absence of lingual papilla; presence of fejervaryan lines; finger and toe tips rounded with slightly swollen discs, without circum-marginal grooves; and foot webbing not extending up to the toe tips.
Andaman and Nicobar Archipelago of India (Fig.
Distribution of Minervarya species in the Andaman and Nicobar Archipelago. A Location of the Archipelago in the Bay of Bengal. B Expanded view of the Andaman and Nicobar groups of islands. C Minervarya nicobariensis in the Nicobar Islands. D Minervarya charlesdarwini in the Andaman Islands. E Minervarya andamanensis in the Andaman Islands. F Minervarya agricola in the Andaman Islands.
Morphological variation in skin colouration and markings observed among individuals of Minervarya charlesdarwini in the Andaman Islands. A–N Dorsolateral views. A SDBDU 2021.4212 (♂). B–C SDBDU 2019.4059 (♀). D Not preserved. E SDBDU 2019.4006 (♂). F SDBDU 2019.3975 (♂). G SDBDU 2021.4212 (♂). H SDBDU 2019.4005 (♀). I SDBDU 2019.3968 (♀). J SDBDU 2019.4004 (♂). K SDBDU 2021.4213 (♀). L SDBDU 2020.4165 (♀). M SDBDU 2019.3946 (♀). N SDBDU 2021.4214 (♀). Photographs: S. D. Biju, G. Gokulakrishnan & Sonali Garg.
Morphological variation in skin texture, colouration, and markings observed among individuals of Minervarya charlesdarwini in the Andaman Islands. A–H Dorsal views. A–D Variation in skin texture and enlarged view of dorsal skin (demarcated with white square) above. A SDBDU 2019.4059 (♀). B SDBDU 2020.4162 (♂). C SDBDU 2021.4212 (♂). D SDBDU 2019.3977 (♂). E–G Not preserved (♂). H SDBDU 2019.4004 (♂). I SDBDU 2019.4005 (♀). J Ventral view, SDBDU 2021.4212 (♂). K Lateral view, SDBDU 2021.4218 (♂). L Dorsal view of thigh, SDBDU 2021.4212 (♂). M Posterior view of thigh, SDBDU 2021.4212 (♂). N Ventral view of hand, SDBDU 2021.4212 (♂). O Ventral view of foot, SDBDU 2021.4212 (♂). P Schematic illustration of foot webbing, SDBDU 2021.4212 (♂). Photographs: S. D. Biju.
Minervarya charlesdarwini can be morphologically diagnosed by the following suite of characters: small to medium-sized adults (male SVL 24.8–30.1 mm, female SVL 30.8–36.6 mm); rather elongate body; dorsal skin shagreened to granular, or with prominently glandular warts; presence or absence of a weakly to well developed interrupted inverse V-shaped ridge (chevron mark) at the centre of dorsum; upper ⅔rd of tympanum and inner margin of tympanic fold dark brown; groin and thighs without prominent reticulations; finger and toe tips rounded with slightly swollen discs, without circum-marginal grooves; foot webbing relatively reduced, up to or just above the second subarticular tubercle but not beyond on either side of toe IV; elongate inner metatarsal tubercles; small and rounded outer metatarsal tubercle; presence of fejervaryan lines on abdomen; vomerine ridge with weakly developed teeth; absence of lingual papilla; omosternum unforked.
A small to medium-sized species (males: SVL 24.8–30.1, 26.6±1.8, N=6; females: SVL 30.8–36.6, 33.5±1.9, N=7), body rather elongate; head longer (males: HL 10.0–12.0, 10.6±0.7; females: HL 11.1–13.8, 12.7±1.0, N=7) than wide (males: HW 9.0–10.9, 9.6±0.7; females: HW 10.4–12.4, 11.6±0.7, N=7); snout rounded in dorsal and lateral view; snout length (males: SL 4.2–4.4, 4.3±0.1, N=6; females: SL 4.7–5.7, 5.2±0.4, N=7) longer than horizontal diameter of eye (males: EL 3.1–3.9, 3.4±0.3, N=6; females: EL 3.6–4.5, 4.0±0.3, N=7); loreal region obtuse; canthus rostralis rounded; interorbital space flat; tympanum diameter (males: TYD 1.9–2.3, 2.1± 0.2, N=6; females: TYD 2.1–2.8, 2.5±0.3, N=7) nearly ⅗th of the eye diameter (males: EL 3.1–3.9, 3.4±0.3, N=6; females: EL 3.6–4.5, 4.0±0.3, N=7); pineal ocellus present; supratympanic fold well developed, extends from posterior corner of the eye up to nearly the shoulder; vomerine ridge present, bearing small teeth; tongue moderately long, emarginated; 1–4 glands present at labial commissure (Figs
Forearm length (males: FAL 4.8–6.0, 5.3±0.5, N=6; females: FAL 6.0–6.9, 6.6±0.3, N=7) shorter than hand length (males: HAL 6.1–7.8, 6.7±0.6, N=6; females: HAL 7.4–8.7, 8.1±0.6, N=7); subarticular tubercles prominent, single, circular, all present; prepollex oval, prominent; two rounded palmar tubercles; supernumerary tubercles absent; relative length of fingers II < I=IV < III; tip of fingers rounded, not enlarged into discs. Hind limbs short in comparison to the body length with tibiotarsal articulation reaching up to the anterior end of eye when hind limb is stretched along the body; thigh (males: TL 13.1–15.4, 13.6±0.9, N=6; females: TL 16.2–17.0, 16.6±0.4, N=7) shorter than shank (males: SHL 14.1–15.8, 14.5±0.6, N=6; females: SHL 17.5–18.9, 18.0±0.7, N=7) and nearly equal to foot (males: FOL 12.8–15.3, 13.4±1.0, N=6; females: FOL 15.9–17.7, 16.8±0.7, N=7); total foot length (males: TFOL 19.1–22.7, 19.7±1.6, N=6; females: TFOL 23.0–26.1, 24.7±1.2, N=7); toe tips rounded, slightly swollen without discs, toes without dermal fringes, foot webbing moderate: I2––2II1½–3–III2––3+IV3––2–V; subarticular tubercles prominent, all present; inner metatarsal tubercle prominent, elongate; outer metatarsal tubercle small, rounded; supernumerary tubercles absent.
Skin of dorsum highly variable from shagreened to prominently granular or with glandular warts; an interrupted inverse V-shaped ridge (chevron mark) at the centre of dorsum weakly to well developed or absent. Ventral surfaces of throat, chest, belly, and limbs smooth; and posterior parts of thigh and region surrounding the vent sparsely granular (Fig.
Minervarya charlesdarwini cannot be confused with other known species of the genus Minervarya, except three members of the M. andamanensis group (M. andamanensis, M. nicobariensis, and M. muangkanensis). Minervarya charlesdarwini can be distinguished from M. andamanensis and M. nicobariensis by its relatively smaller adult size, male SVL 24.8–30.1 mm (vs. larger, SVL 36.2–42.2 mm and SVL 40.0–49.8 mm, respectively); and elongate body (vs. stout and robust in both the species). It specifically also differs from M. andamanensis by the absence of forearm tubercles (vs. present); canthus rostralis rounded (vs. indistinct); posterior half of thigh without reticulations, usually brown or orangish-brown (vs. light to dark brown with yellowish reticulations); upper eyelid width nearly equal to inter upper eyelid width, UEW 2.4±0.2 vs. IUE 2.4±0.2 (vs. wider, UEW 3.6±0.3 vs. IUE 2.8±0.1); and thigh nearly equal to foot length, TL 13.6±0.9 vs. FOL 13.4±1.0 (vs. shorter, TL 19.9±1.3 vs. FOL 21.7±1.5). Minervarya charlesdarwini also differs from M. nicobariensis by its head being longer than wide, HL 10.6±0.7 vs. HW 9.6±0.7 (vs. wider, HW 17.5±1.0 vs. HL 16.5±1.1); upper eyelid width nearly equal to inter upper eyelid width, UEW 2.4±0.2 vs. IUE 2.4±0.2 (vs. wider, UEW 4.5±0.4 vs IUE 3.2±0.4); thigh nearly equal to foot length, TL 13.6±0.9 vs. FOL 13.4±1.0 (vs. shorter, TL 20.7±1.4 vs. FOL 22.1±1.5); presence of outer metatarsal (vs. absent); and posterior part of thighs without prominent reticulations, usually brown or orangish-brown (vs. light to dark red with thin black reticulations). Further, M. charlesdarwini differs from M. muangkanensis, a species endemic to Thailand and Myanmar, in possessing a distinct supratympanic fold that extends from posterior corner of upper eyelid, along the upper margin of tympanum, up to the shoulder (vs. indistinct supratympanic fold, and not extending up to posterior corner of upper eyelid and down to the shoulder); webbing between toes relatively reduced, up to the second subarticular tubercle on either side of toe IV (vs. above); and posterior part of thighs without reticulations, usually brown or orangish-brown (vs. light to dark brown with yellowish reticulations).
Minervarya charlesdarwini is endemic to the Andaman Archipelago of India, where we find it to be widely distributed in all the major groups of islands: North and Middle Andamans (North Andaman Is., Interview Is., Middle Andaman Is., Baratang Is., and Long Is.), South Andamans (South Andaman Is., Neil Is., Havelock Is., Boat Is., Red Skin Is., Alexandra Is., Rutland Is., and Tarmugli Is.), up to the Little Andaman Island. This species has been observed between elevations of nearly sea level up to 600 m asl (Fig.
Distribution of Minervarya species reported in the present study from the Andaman and Nicobar Islands, India.
District / Group | Island / Locality | Coordinates | Elevation | ||
---|---|---|---|---|---|
Latitude (°N) | Longitude (°E) | (meters) | |||
Minervarya andamanensis | |||||
1 | North Andaman | Landfall Island | 13.6680 | 93.0190 | 2 |
2 | North Andaman | Landfall Island | 13.6630 | 93.0217 | 33 |
3 | North Andaman | Landfall Island | 13.6406 | 93.0304 | 0.4 |
4 | North Andaman | East Island | 13.6333 | 93.0450 | 9 |
5 | North Andaman | Landfall Island – South East | 13.6299 | 93.0298 | 14 |
6 | North Andaman | East Island | 13.6285 | 93.0481 | 30 |
7 | North Andaman | Paget Island | 13.4321 | 92.8438 | 25 |
8 | North Andaman | Hathi Level | 13.4068 | 92.9094 | 8 |
9 | North Andaman | Badur Tikrey | 13.3685 | 92.9632 | 13 |
10 | North Andaman | Smith Island | 13.3494 | 93.0570 | 4 |
11 | North Andaman | Smith Island | 13.3465 | 93.0527 | 8 |
12 | North Andaman | Aerial Bay | 13.2728 | 93.0319 | 18 |
13 | North Andaman | Durgapur | 13.2711 | 93.0376 | 4 |
14 | North Andaman | Kishori Nagar | 13.2711 | 92.9596 | 63 |
15 | North Andaman | Durgapur | 13.2672 | 93.0382 | 24 |
16 | North Andaman | Durgapur | 13.2644 | 93.0407 | 18 |
17 | North Andaman | Madhupur | 13.2589 | 92.9805 | 13 |
18 | North Andaman | Madhupur | 13.2585 | 92.9772 | 13 |
19 | North Andaman | Khudirampur | 13.2361 | 92.9768 | 11 |
20 | North Andaman | Shibpur | 13.2339 | 93.0490 | 8 |
21 | North Andaman | Kalipur | 13.2240 | 93.0454 | 5 |
22 | North Andaman | Lamiya Bay | 13.2037 | 93.0408 | 10 |
23 | North Andaman | Khudirampur | 13.2033 | 92.9691 | 36 |
24 | North Andaman | Kishori Nagar | 13.2025 | 92.9690 | 31 |
25 | North Andaman | Lamiya Bay | 13.2010 | 93.0380 | 36 |
26 | North Andaman | Khudirampur | 13.1994 | 92.9731 | 41 |
27 | North Andaman | Saddle Peak | 13.1967 | 93.0314 | 34 |
28 | North Andaman | Lamiya Bay | 13.1930 | 93.0340 | 53 |
29 | North Andaman | Sita Nagar | 13.1881 | 92.9290 | 43 |
30 | North Andaman | Saddle Peak | 13.1860 | 93.0260 | 57 |
31 | North Andaman | Sita Nagar | 13.1853 | 92.9246 | 92 |
32 | North Andaman | Saddle Peak | 13.1850 | 93.0190 | 224 |
33 | North Andaman | Kalara | 13.1752 | 92.9341 | 47 |
34 | North Andaman | Kalpong Dam | 13.1140 | 92.9971 | 60 |
35 | North Andaman | Kalighat | 13.1013 | 92.9912 | 40 |
36 | North Andaman | Ram Nagar | 13.0800 | 93.0151 | 22 |
37 | North Andaman | Ram Nagar | 13.0724 | 93.0145 | 28 |
38 | North Andaman | Patti Level | 13.0596 | 92.9907 | 123 |
39 | North Andaman | Interview Island | 12.8999 | 92.7200 | 20 |
40 | Middle Andaman | Mayabunder, Austin Strait | 12.8934 | 92.8574 | 28 |
41 | Middle Andaman | Mayabunder, Tugapur | 12.8395 | 92.8568 | 13 |
42 | Middle Andaman | Mayabunder, Hanspuri | 12.7581 | 92.8059 | 74 |
43 | Middle Andaman | Mayabunder, Chainpur | 12.7396 | 92.8068 | 28 |
44 | Middle Andaman | Rangat, Cuthbert Bay | 12.7090 | 92.9680 | 7 |
45 | Middle Andaman | Rangat, Mount Diavalo | 12.6800 | 92.9400 | 156 |
46 | Middle Andaman | Rangat, Mount Diavalo | 12.6800 | 92.9420 | 98 |
47 | Middle Andaman | Rangat, Dhanni Nallah | 12.6160 | 92.9550 | 11 |
48 | Middle Andaman | Rangat, Moricedera | 12.5535 | 92.9712 | 17 |
49 | Middle Andaman | Rangat, Parnashala | 12.5265 | 92.9053 | 26 |
50 | Middle Andaman | Rangat, Yeratta | 12.5038 | 92.9028 | 40 |
51 | Middle Andaman | Rangat, Bakultala | 12.5015 | 92.8857 | 119 |
52 | Middle Andaman | Rangat, Shyamkund | 12.4910 | 92.8480 | 38 |
53 | Middle Andaman | Rangat, Sabari | 12.4861 | 92.9002 | 13 |
54 | Middle Andaman | Rangat, Vishnupur | 12.4840 | 92.8734 | 17 |
55 | Middle Andaman | Rangat, Vishnupur | 12.4756 | 92.8766 | 7 |
56 | Middle Andaman | Rangat, Ullidera | 12.4718 | 92.8613 | 9 |
57 | Middle Andaman | Rangat, Ullidera | 12.4715 | 92.8634 | 10 |
58 | Middle Andaman | Rangat, Bharatpur | 12.4680 | 92.8930 | 16 |
59 | Middle Andaman | Rangat, Bronil | 12.4631 | 92.8312 | 5 |
60 | Middle Andaman | Rangat, Panchawati | 12.4078 | 92.8877 | 9 |
61 | Middle Andaman | Long Island, Sigman Dera | 12.3820 | 92.9290 | 37 |
62 | Middle Andaman | Long Island, Lalaji Bay Forest | 12.3790 | 92.9350 | 60 |
63 | Middle Andaman | Long Island | 12.3710 | 92.9220 | 60 |
64 | Middle Andaman | North Passage Island | 12.2880 | 92.9334 | 12 |
65 | Middle Andaman | Baratang Island, Shankar Nallah | 12.2543 | 92.8041 | 64 |
66 | Middle Andaman | Baratang Island, Shankar Nallah | 12.2543 | 92.8041 | 67 |
67 | Middle Andaman | Baratang Island, Loroijg | 12.2389 | 92.7957 | 37 |
68 | Middle Andaman | Baratang Island, Roglachang | 12.1603 | 92.7936 | 26 |
69 | Middle Andaman | Baratang Island, Baludera | 12.1363 | 92.8069 | 8 |
70 | Middle Andaman | Baratang Island, Baludera | 12.1357 | 92.8032 | 4 |
71 | Middle Andaman | Baratang Island, Jarawa Creek | 12.1250 | 92.7881 | 18 |
72 | Middle Andaman | Baratang Island, Wrafters Creek | 12.1127 | 92.7680 | 45 |
73 | Middle Andaman | Baratang Island, Wrafters Creek | 12.1105 | 92.7725 | 21 |
74 | Middle Andaman | Baratang Island, Wrafters Creek | 12.1066 | 92.7722 | 12 |
75 | Middle Andaman | Baratang Island, Naya Dera | 12.0974 | 92.7535 | 54 |
76 | South Andaman | Jirkatang – 21km | 12.0930 | 92.7070 | 73 |
77 | South Andaman | Jarawa Reserve | 12.0581 | 92.7128 | 59 |
78 | South Andaman | Jarawa Reserve, Jirkatang – 16km | 12.0560 | 92.7020 | 89 |
79 | South Andaman | Havelock Island, Govind Nagar | 12.0418 | 92.9831 | 6 |
80 | South Andaman | Havelock Island, Shyam Nagar | 12.0087 | 92.9635 | 58 |
81 | South Andaman | Havelock Island, Krishna Nagar | 12.0076 | 92.9612 | 61 |
82 | South Andaman | Jarawa Reserve, Jirkatang – 6km | 11.9650 | 92.6770 | 105 |
83 | South Andaman | Jirkatang | 11.9453 | 92.6812 | 127 |
84 | South Andaman | Jirkatang | 11.9060 | 92.6660 | 132 |
85 | South Andaman | Shoal Bay – 19 | 11.8967 | 92.7662 | 33 |
86 | South Andaman | Shoal Bay – 19 | 11.8950 | 92.7650 | 16 |
87 | South Andaman | Shoal Bay – 1 | 11.8820 | 92.7470 | 56 |
88 | South Andaman | Shoal Bay | 11.8770 | 92.7410 | 31 |
89 | South Andaman | Shoal Bay | 11.8747 | 92.7402 | 23 |
90 | South Andaman | Shoal Bay | 11.8746 | 92.7406 | 32 |
91 | South Andaman | Shoal Bay | 11.8710 | 92.7420 | 87 |
92 | South Andaman | Jirkatang | 11.8680 | 92.6550 | 82 |
93 | South Andaman | Shoal Bay | 11.8570 | 92.7350 | 21 |
94 | South Andaman | Shoal Bay 10 | 11.8438 | 92.7293 | 6 |
95 | South Andaman | Shoal Bay 10 | 11.8410 | 92.7290 | 35 |
96 | South Andaman | Neil Island | 11.8354 | 93.0362 | 6 |
97 | South Andaman | Shoal Bay – 8 | 11.8270 | 92.7220 | 9 |
98 | South Andaman | Kalatang | 11.8050 | 92.7140 | 27 |
99 | South Andaman | Wrightmayo Creek | 11.8010 | 92.7080 | 16 |
100 | South Andaman | Kalatang | 11.7958 | 92.7118 | 18 |
101 | South Andaman | Mount Harriet | 11.7570 | 92.7320 | 308 |
102 | South Andaman | Mount Harriet | 11.7440 | 92.7390 | 285 |
103 | South Andaman | Wimberlygunj | 11.7375 | 92.7132 | 42 |
104 | South Andaman | Kadakachang, Stewartgunj 1 | 11.7330 | 92.7150 | 61 |
105 | South Andaman | Tirur | 11.7312 | 92.6146 | 10 |
106 | South Andaman | Mount Harriet | 11.7290 | 92.7420 | 87 |
107 | South Andaman | Mount Harriet | 11.7250 | 92.7370 | 211 |
108 | South Andaman | Kadakachang, Mathura | 11.7230 | 92.6810 | 16 |
109 | South Andaman | Mount Harriet | 11.7202 | 92.7339 | 351 |
110 | South Andaman | Katagachang | 11.7160 | 92.6940 | 18 |
111 | South Andaman | Tirur–Jhau kona Hotspot | 11.7123 | 92.5727 | 49 |
112 | South Andaman | Mazar Pahad | 11.7030 | 92.6370 | 12 |
113 | South Andaman | Gandhi Park | 11.6617 | 92.7408 | 45 |
114 | South Andaman | Ograbraj | 11.6577 | 92.6631 | 4 |
115 | South Andaman | Rachibasthi | 11.6469 | 92.7280 | 61 |
116 | South Andaman | Corbyns Cove | 11.6434 | 92.7442 | 12 |
117 | South Andaman | BSI Garden | 11.6390 | 92.7367 | 16 |
118 | South Andaman | Garacharma | 11.6238 | 92.7041 | 17 |
119 | South Andaman | Chouldhari | 11.6225 | 92.6685 | 3 |
120 | South Andaman | Garacharma | 11.6180 | 92.7062 | 2 |
121 | South Andaman | Wandoor | 11.6177 | 92.6167 | 15 |
122 | South Andaman | Wandoor | 11.6149 | 92.6190 | 15 |
123 | South Andaman | Sippighat | 11.6125 | 92.6931 | 11 |
124 | South Andaman | Bathu Basti | 11.6120 | 92.7183 | 58 |
125 | South Andaman | Tarmugli Island, Mummy Dera | 11.6028 | 92.5413 | 12 |
126 | South Andaman | Tarmugli Island | 11.5935 | 92.5437 | 19 |
127 | South Andaman | Alexandra Island | 11.5851 | 92.6031 | 15 |
128 | South Andaman | Alexandra Island | 11.5850 | 92.6060 | 40 |
129 | South Andaman | Alexandra Island | 11.5770 | 92.6030 | 39 |
130 | South Andaman | Tarmugli Island | 11.5650 | 92.5523 | 24 |
131 | South Andaman | Boat Island | 11.5329 | 92.5579 | 24 |
132 | South Andaman | Boat Island | 11.5268 | 92.5652 | 18 |
133 | South Andaman | Boat Island | 11.5240 | 92.5600 | 33 |
134 | South Andaman | Burmanallah | 11.5225 | 92.7209 | 40 |
135 | South Andaman | Chidiyatapu | 11.5162 | 92.6992 | 13 |
136 | South Andaman | Chidyatapu | 11.5081 | 92.6915 | 10 |
137 | South Andaman | Rutland Island | 11.5080 | 92.6439 | 40 |
138 | South Andaman | Rutland Island | 11.5078 | 92.6436 | 36 |
139 | South Andaman | Rutland Island | 11.5066 | 92.6426 | 39 |
140 | Little Andaman | V. K. Pur | 10.7590 | 92.5530 | 23 |
141 | Little Andaman | V. K. Pur | 10.7460 | 92.5410 | 26 |
142 | Little Andaman | Donghighat | 10.7379 | 92.5703 | 12 |
143 | Little Andaman | Rabinder Nagar Dam | 10.7150 | 92.5360 | 71 |
144 | Little Andaman | Rabinder Nagar Dam | 10.7080 | 92.5350 | 63 |
145 | Little Andaman | Rabinder Nagar Dam | 10.7050 | 92.5430 | 68 |
146 | Little Andaman | RK Pur Dam | 10.7020 | 92.5490 | 44 |
147 | Little Andaman | Krishna Nala | 10.6783 | 92.5396 | 72 |
148 | Little Andaman | Krishna Nala | 10.6710 | 92.5130 | 114 |
149 | Little Andaman | Netaji Nagar | 10.6630 | 92.5440 | 29 |
150 | Little Andaman | Kalapather | 10.6597 | 92.5765 | 5 |
151 | Little Andaman | Netaji Nagar | 10.6493 | 92.5409 | 57 |
152 | Little Andaman | White Surf Water Fall | 10.6290 | 92.5280 | 87 |
153 | Little Andaman | Rabinder Nagar Dam | 10.5945 | 92.5326 | -1 |
154 | Little Andaman | Farm Tikery | 10.5890 | 92.5241 | 73 |
155 | Little Andaman | Herimidhar Bay | 10.5870 | 92.5330 | 4 |
156 | Little Andaman | Ongi Tikery | 10.5710 | 92.5540 | 34 |
Minervarya charlesdarwini | |||||
157 | North Andaman | Hathi Level | 13.4068 | 92.9094 | 6 |
158 | North Andaman | Badur Tikrey | 13.3685 | 92.9632 | 13 |
159 | North Andaman | Kishori Nagar | 13.2711 | 92.95955 | 62 |
160 | North Andaman | Durgapur | 13.2672 | 93.0382 | 23 |
161 | North Andaman | Lamiya Bay | 13.2037 | 93.0408 | 10 |
162 | North Andaman | Khudirampur | 13.2033 | 92.9691 | 36 |
163 | North Andaman | Khudirampur | 13.2026 | 93.0375 | 72 |
164 | North Andaman | Kishori Nagar | 13.2025 | 92.9690 | 31 |
165 | North Andaman | Lamiya Bay | 13.2010 | 93.0380 | 36 |
166 | North Andaman | Saddle Peak | 13.1967 | 93.0314 | 72 |
167 | North Andaman | Lamiya Bay | 13.1930 | 93.0340 | 54 |
168 | North Andaman | Saddle Peak | 13.1860 | 93.0260 | 54 |
169 | North Andaman | Saddle Peak | 13.1850 | 93.0190 | 219 |
170 | North Andaman | Kalara | 13.1752 | 92.9341 | 47 |
171 | North Andaman | Kalpong Dam | 13.1140 | 92.9971 | 59 |
172 | North Andaman | Ram Nagar | 13.0800 | 93.0151 | 8 |
173 | North Andaman | Patti Level | 13.0596 | 92.9907 | 122 |
174 | North Andaman | Interview Island | 12.8999 | 92.7200 | 22 |
175 | North Andaman | Interview Island | 12.8953 | 92.6884 | 78 |
176 | Middle Andaman | Mayabunder, Austin Strait | 12.8934 | 92.8574 | 28 |
177 | Middle Andaman | Mayabunder, Tugapur | 12.8395 | 92.8568 | 13 |
178 | Middle Andaman | Mayabunder, Hanspuri | 12.7581 | 92.8059 | 73 |
179 | Middle Andaman | Mayabunder, Chainpur | 12.7396 | 92.8068 | 28 |
180 | Middle Andaman | Rangat, Mount Diavalo | 12.6800 | 92.9420 | 99 |
181 | Middle Andaman | Rangat, Moricedera | 12.5535 | 92.9712 | 15 |
182 | Middle Andaman | Rangat, Parnashala | 12.5265 | 92.9053 | 24 |
183 | Middle Andaman | Rangat, Yeratta | 12.5038 | 92.9028 | 36 |
184 | Middle Andaman | Rangat, Bakultala | 12.5015 | 92.8857 | 119 |
185 | Middle Andaman | Rangat, Shyamkund | 12.4910 | 92.8480 | 36 |
186 | Middle Andaman | Rangat, Sabari | 12.4861 | 92.9002 | 12 |
187 | Middle Andaman | Rangat, Vishnupur | 12.4840 | 92.8734 | 63 |
188 | Middle Andaman | Rangat, Ullidera | 12.4715 | 92.8634 | 15 |
189 | Middle Andaman | Rangat, Bharatpur | 12.4680 | 92.8930 | 16 |
190 | Middle Andaman | Rangat, Bronil | 12.4631 | 92.8312 | 5 |
191 | Middle Andaman | Rangat, Panchawati | 12.4078 | 92.8877 | 8 |
192 | Middle Andaman | Long Island, Sigman Dera | 12.3820 | 92.9290 | 38 |
193 | Middle Andaman | Long Island, Lalaji Bay Forest | 12.3790 | 92.9350 | 60 |
194 | Middle Andaman | Long Island, Long Island | 12.3710 | 92.9220 | 60 |
195 | Middle Andaman | Baratang Island, Shankar Nallah | 12.2543 | 92.8041 | 68 |
196 | Middle Andaman | Baratang Island, Shankar Nallah | 12.2543 | 92.8041 | 68 |
197 | Middle Andaman | Baratang Island, Loroijg | 12.2389 | 92.7957 | 37 |
198 | Middle Andaman | Baratang Island, Roglachang | 12.1603 | 92.7936 | 21 |
199 | Middle Andaman | Baratang Island, Baludera | 12.1357 | 92.8032 | 5 |
200 | Middle Andaman | Baratang Island, Jarawa Creek | 12.1250 | 92.7881 | 17 |
201 | Middle Andaman | Baratang Island, Wrafters Creek | 12.1127 | 92.7680 | 46 |
202 | Middle Andaman | Baratang Island, Wrafters Creek | 12.1105 | 92.7725 | 21 |
203 | Middle Andaman | Baratang Island, Naya Dera | 12.0974 | 92.7535 | 54 |
204 | South Andaman | Jirkatang – 21km | 12.0930 | 92.7070 | 73 |
205 | South Andaman | Jirkatang – 16km | 12.0560 | 92.7020 | 85 |
206 | South Andaman | Jirkatang – 6km | 11.9650 | 92.6770 | 106 |
207 | South Andaman | Jirkatang | 11.9453 | 92.6812 | 126 |
208 | South Andaman | Jirkatang | 11.9060 | 92.6660 | 133 |
209 | South Andaman | Shoal Bay – 19 | 11.8950 | 92.7650 | 16 |
210 | South Andaman | Shoal Bay – 19 | 11.8910 | 92.7790 | 13 |
211 | South Andaman | Shoal Bay – 1 | 11.8820 | 92.7470 | 57 |
212 | South Andaman | Shoal Bay | 11.8770 | 92.7410 | 29 |
213 | South Andaman | Shoal Bay | 11.8747 | 92.7402 | 25 |
214 | South Andaman | Shoal Bay | 11.8746 | 92.7406 | 55 |
215 | South Andaman | Shoal Bay | 11.8746 | 92.7406 | 55 |
216 | South Andaman | Shoal Bay | 11.8710 | 92.7420 | 87 |
217 | South Andaman | Jirkatang | 11.8680 | 92.6550 | 83 |
218 | South Andaman | Shoal Bay | 11.8570 | 92.7350 | 21 |
219 | South Andaman | Shoal Bay – 10 | 11.8410 | 92.7290 | 37 |
220 | South Andaman | Neil Island | 11.8354 | 93.0362 | 6 |
221 | South Andaman | Shoal Bay – 8 | 11.8270 | 92.7220 | 9 |
222 | South Andaman | Kalatang | 11.8050 | 92.7140 | 23 |
223 | South Andaman | Wrightmayo Creek | 11.8010 | 92.7080 | 15 |
224 | South Andaman | Boat Island, Kalatang | 11.7958 | 92.7118 | 19 |
225 | South Andaman | Mount Harriet | 11.7570 | 92.7320 | 310 |
226 | South Andaman | Tirur–Jhau Kona Hotspot | 11.7510 | 92.6120 | 12 |
227 | South Andaman | Mount Harriet | 11.7440 | 92.7390 | 387 |
228 | South Andaman | Mount Harriet | 11.7290 | 92.7420 | 87 |
229 | South Andaman | Mount Harriet | 11.7250 | 92.7370 | 197 |
230 | South Andaman | Mount Harriet | 11.7202 | 92.7339 | 351 |
231 | South Andaman | Tirur–Jhau Kona Hotspot | 11.7190 | 92.5850 | 17 |
232 | South Andaman | Mazar Pahad | 11.7030 | 92.6370 | 12 |
233 | South Andaman | Gandhi Park | 11.6617 | 92.7408 | 46 |
234 | South Andaman | BSI Garden | 11.6390 | 92.7367 | 18 |
235 | South Andaman | Wandoor | 11.6149 | 92.6190 | 15 |
236 | South Andaman | Tarmugli Island | 11.6028 | 92.5413 | 11 |
237 | South Andaman | Alexandra Island | 11.5850 | 92.6060 | 42 |
238 | South Andaman | Alexandra Island | 11.5770 | 92.6030 | 38 |
239 | South Andaman | Redskin Island | 11.5691 | 92.5931 | 34 |
240 | South Andaman | Chidiyatapu | 11.5162 | 92.6992 | 13 |
241 | South Andaman | Chidyatapu | 11.5081 | 92.6915 | 11 |
242 | South Andaman | Rutland Island | 11.5080 | 92.6439 | 40 |
243 | South Andaman | Rutland Island | 11.5078 | 92.6436 | 36 |
244 | South Andaman | Rutland Island | 11.5066 | 92.6426 | 37 |
245 | Little Andaman | V. K. Pur | 10.7590 | 92.5530 | 21 |
246 | Little Andaman | V. K. Pur | 10.7460 | 92.5410 | 27 |
247 | Little Andaman | Donghighat | 10.7410 | 92.5750 | 17 |
248 | Little Andaman | Rabinder Nagar Dam | 10.7150 | 92.5360 | 67 |
249 | Little Andaman | Rabinder Nagar Dam | 10.7080 | 92.5350 | 62 |
250 | Little Andaman | Rabinder Nagar Dam | 10.7050 | 92.5430 | 70 |
251 | Little Andaman | RK Pur Dam | 10.7020 | 92.5490 | 45 |
252 | Little Andaman | Krishna Nallah | 10.6783 | 92.5396 | 72 |
253 | Little Andaman | Krishna Nalla | 10.6710 | 92.5130 | 117 |
254 | Little Andaman | Netaji Nagar | 10.6630 | 92.5440 | 30 |
255 | Little Andaman | Netaji Nagar | 10.6493 | 92.5409 | 60 |
256 | Little Andaman | Kalapather | 10.6407 | 92.5423 | 5 |
257 | Little Andaman | White Surf Water Fall | 10.6290 | 92.5280 | 88 |
258 | Little Andaman | Rabinder Dam | 10.5945 | 92.5326 | -1 |
Minervarya nicobariensis | |||||
259 | Nicobar, Central group | Bompoka Island | 8.2494 | 93.2218 | 36 |
260 | Nicobar, Central group | Kamorta Island, Kakana | 8.1731 | 93.5070 | 22 |
261 | Nicobar, Central group | Kamorta Island, Vikas Nagar | 8.1198 | 93.5138 | 31 |
262 | Nicobar, Central group | Kamorta Island, Changhua | 8.0212 | 93.4916 | 72 |
263 | Nicobar, Central group | Nancowry Island, Champin | 8.0202 | 93.5548 | 63 |
264 | Nicobar, Central group | Kamorta Island, Munak | 8.0123 | 93.5045 | 69 |
265 | Nicobar, Central group | Kamorta Island, Alukian | 8.0057 | 93.4932 | 63 |
266 | Nicobar, Central group | Nancowry Island, Malacca | 8.0053 | 93.5675 | 73 |
267 | Nicobar, Central group | Katchal Island, Kapanga | 7.9992 | 93.3928 | 85 |
268 | Nicobar, Central group | Katchal Island, Beachdera | 7.9969 | 93.3585 | 62 |
269 | Nicobar, Central group | Nancowry Island, Itoi | 7.9961 | 93.5315 | 74 |
270 | Nicobar, Central group | Katchal Island, Lal Munak | 7.9879 | 93.3737 | 52 |
271 | Nicobar, Central group | Katchal Island, Upper Katchal | 7.9407 | 93.4434 | 69 |
272 | Nicobar, Southern group | Little Nicobar Island, Makachua | 7.4069 | 93.7096 | 41 |
273 | Nicobar, Southern group | Little Nicobar Island, Pulo Panja | 7.3760 | 93.7395 | 39 |
274 | Nicobar, Southern group | Great Nicobar Island, Afra Bay | 7.1662 | 93.7662 | 166 |
275 | Nicobar, Southern group | Great Nicobar Island, Navy Dera | 7.1353 | 93.8840 | 38 |
276 | Nicobar, Southern group | Great Nicobar Island, Navy Dera | 7.1239 | 93.8870 | 34 |
277 | Nicobar, Southern group | Great Nicobar Island, Laxman Beach | 7.0214 | 93.9176 | 27 |
278 | Nicobar, Southern group | Great Nicobar Island, East West Road | 7.0189 | 93.9233 | 36 |
279 | Nicobar, Southern group | Great Nicobar Island, Old East West Road | 7.0176 | 93.9231 | 28 |
280 | Nicobar, Southern group | Great Nicobar Island, Campbell Bay | 7.0152 | 93.9230 | 40 |
281 | Nicobar, Southern group | Great Nicobar Island, Govind Nagar | 7.0040 | 93.9095 | 52 |
282 | Nicobar, Southern group | Great Nicobar Island, GNBR Check Post | 7.0016 | 93.8834 | 56 |
283 | Nicobar, Southern group | Great Nicobar Island, Govind Nagar | 7.0011 | 93.8958 | 40 |
284 | Nicobar, Southern group | Great Nicobar Island, East West Road | 6.9957 | 93.8831 | 49 |
285 | Nicobar, Southern group | Great Nicobar Island, Magar Nallah | 6.9945 | 93.9124 | 18 |
286 | Nicobar, Southern group | Great Nicobar Island, East West Road | 6.9814 | 93.8644 | 92 |
287 | Nicobar, Southern group | Great Nicobar Island, Chingam Basti | 6.9705 | 93.9192 | 106 |
288 | Nicobar, Southern group | Great Nicobar Island, Jogindar Nagar | 6.9513 | 93.9199 | 13 |
289 | Nicobar, Southern group | Great Nicobar Island, Laxmi Nagar | 6.9039 | 93.8920 | 35 |
290 | Nicobar, Southern group | Great Nicobar Island, Vijay Nagar | 6.8729 | 93.8893 | 50 |
291 | Nicobar, Southern group | Great Nicobar Island, Gandhi Nagar | 6.8404 | 93.8907 | 14 |
292 | Nicobar, Southern group | Great Nicobar Island, Galathea Bay | 6.8231 | 93.8631 | 32 |
293 | Nicobar, Southern group | Great Nicobar Island, Sastri Nagar | 6.8104 | 93.8920 | 37 |
294 | Nicobar, Southern group | Great Nicobar Island, Old Chingam Basti | 6.8026 | 93.8458 | 34 |
295 | Nicobar, Southern group | Great Nicobar Island, Indira Point | 6.7597 | 93.8257 | 35 |
Minervarya agricola | |||||
296 | North Andaman | Badur Tikrey | 13.3685 | 92.9632 | 18 |
297 | North Andaman | Ram Nagar | 13.2759 | 93.0186 | 7 |
298 | North Andaman | Durgapur | 13.2671 | 93.0382 | 22 |
299 | North Andaman | Madhupur | 13.2585 | 92.9772 | 10 |
300 | North Andaman | Shibpur | 13.2339 | 93.0490 | 7 |
301 | North Andaman | Khudirampur | 13.2033 | 92.9691 | 34 |
302 | North Andaman | Kishori Nagar | 13.2025 | 92.9690 | 31 |
303 | North Andaman | Lamiya Bay | 13.2010 | 93.0380 | 37 |
304 | North Andaman | Lamiya Bay | 13.1930 | 93.0340 | 53 |
305 | North Andaman | Sita Nagar | 13.18533 | 92.9246 | 93 |
306 | Middle Andaman | Mayabunder, Hanspuri | 12.7581 | 92.8059 | 74 |
307 | Middle Andaman | Mayabunder, Chainpur | 12.7396 | 92.8068 | 28 |
308 | Middle Andaman | Rangat, Parnashala | 12.5265 | 92.9053 | 23 |
309 | Middle Andaman | Rangat, Yeratta | 12.5038 | 92.9028 | 41 |
310 | Middle Andaman | Rangat, Shyamkund | 12.4910 | 92.8480 | 36 |
311 | Middle Andaman | Rangat, Sabari | 12.4861 | 92.9002 | 14 |
312 | Middle Andaman | Rangat, Panchawati | 12.4078 | 92.8877 | 7 |
313 | Middle Andaman | Baratang Island, Lolachang | 12.1603 | 92.7936 | 24 |
314 | Middle Andaman | Baratang Island, Baludera | 12.1357 | 92.8032 | 5 |
315 | Middle Andaman | Baratang Island, Wrafters Creek | 12.1127 | 92.7680 | 46 |
316 | Middle Andaman | Baratang Island, Naya Dera | 12.0974 | 92.7535 | 54 |
317 | South Andaman | Havelock Island, Govind Nagar | 12.0337 | 92.9866 | 6 |
318 | South Andaman | Havelock Island, Shyam Nagar | 12.0087 | 92.9635 | 57 |
319 | South Andaman | Havelock Island, Krishna Nagar | 12.0076 | 92.9612 | 62 |
320 | South Andaman | Havelock Island, Kalapather | 11.982 | 93.0161 | 21 |
321 | South Andaman | Jirkatang | 11.9453 | 92.6812 | 127 |
322 | South Andaman | Shoal Bay – 19 | 11.8950 | 92.7650 | 16 |
323 | South Andaman | Shoal Bay – 19 | 11.8910 | 92.7790 | 11 |
324 | South Andaman | Shoal Bay – 1 | 11.8820 | 92.7470 | 57 |
325 | South Andaman | Shoal Bay | 11.8770 | 92.7410 | 29 |
326 | South Andaman | Shoal Bay | 11.8747 | 92.7402 | 27 |
327 | South Andaman | Shoal Bay | 11.8746 | 92.7406 | 29 |
328 | South Andaman | Shoal Bay | 11.8710 | 92.7420 | 88 |
329 | South Andaman | Shoal Bay | 11.8570 | 92.7350 | 21 |
330 | South Andaman | Shoal Bay –10 | 11.8410 | 92.7290 | 37 |
331 | South Andaman | Neil Island | 11.8354 | 93.0362 | 6 |
332 | South Andaman | Shoal Bay – 8 | 11.8270 | 92.7220 | 8 |
333 | South Andaman | Kalatang | 11.7958 | 92.7118 | 19 |
334 | South Andaman | Wimberlygunj | 11.7375 | 92.7132 | 42 |
335 | South Andaman | Kadakachang, Stewartgunj 1 | 11.7330 | 92.7150 | 54 |
336 | South Andaman | Tirur | 11.7288 | 92.6127 | 17 |
337 | South Andaman | Mazar Pahad | 11.7030 | 92.6370 | 12 |
338 | South Andaman | Mazhar Pahad | 11.7028 | 92.6380 | 13 |
339 | South Andaman | Gandhi Park | 11.6617 | 92.7408 | 33 |
340 | South Andaman | Ograbraj | 11.6577 | 92.6631 | 4 |
341 | South Andaman | BSI Garden | 11.6390 | 92.7367 | 16 |
342 | South Andaman | Chouldhari | 11.6225 | 92.6685 | 3 |
343 | South Andaman | Garacharma | 11.6180 | 92.7062 | 2 |
344 | South Andaman | Garacharma | 11.6151 | 92.7000 | 15 |
345 | South Andaman | Wandoor | 11.6149 | 92.6190 | 15 |
346 | South Andaman | Sippighat | 11.6125 | 92.6931 | 12 |
347 | South Andaman | Corbyns Cove | 11.5906 | 92.6749 | 4 |
348 | South Andaman | Burmanallah | 11.5225 | 92.7209 | 37 |
349 | South Andaman | Chidiyatapu | 11.5162 | 92.6992 | 13 |
350 | South Andaman | Chidyatapu | 11.5081 | 92.6915 | 10 |
351 | Little Andaman | V. K. Pur | 10.7460 | 92.5410 | 29 |
352 | Little Andaman | Rabinder Nagar Dam | 10.7080 | 92.5350 | 63 |
353 | Little Andaman | Netaji Nagar | 10.6630 | 92.5440 | 33 |
354 | Little Andaman | Netaji Nagar | 10.6493 | 92.5409 | 59 |
355 | Little Andaman | Kalapather | 10.6407 | 92.5423 | 4 |
356 | Little Andaman | Farm Tikery | 10.5890 | 92.5241 | 72 |
357 | Little Andaman | Ongi Tikery | 10.5710 | 92.5540 | 33 |
This species was originally described as a variety of Rana gracilis var. andamanensis Stoliczka, 1870. The description was based on four specimens—one “about one-third of an inch long” (~9 mm), “two next above one inch” (~ 25 mm), and “the fourth 2⅓rd inches” (~ 60 mm). Of these, ZSIC 3539 (ZSIC 8539 according to Chanda et al. 2001 “2000”) was designated as the lectotype by
A medium-sized species (males: SVL 36.2–42.2, 39.2±2.1, N=6; females: SVL 39.4–57.1, 48.6±7.4, N=6), body stout and robust; head longer in males (HL 14.3–17.0, 15.2±1.0 vs. HW 12.4–15.9, 13.9±1.2, N=6) and subequal in females (HL 14.2–20.9, 17.6±3.1, N=6 vs. HW 13.8–21.6, 17.7±2.9, N=6); snout rounded or subovoid in dorsal and ventral view, rounded or obtuse in lateral view; snout length (males: SL 5.6–7.4, 6.4±0.7; females: SL 5.8–8.6, 7.3±1.1) longer than horizontal diameter of eye (males: EL 4.4–5.4, 4.8±0.5; females: EL 4.0–6.6, 5.2±1.0); loreal region obtuse; indistinct canthus rostralis; interorbital space flat; tympanum diameter (males: TYD 2.4–3.3, 2.8± 0.3; females: TYD 2.9–4.4, 3.3±0.6) nearly ⅗th of the eye diameter (males: EL 4.4–5.4, 4.8±0.5; females: EL 4.0–6.6, 5.2±1.0); pineal ocellus present; supratympanic fold well developed, extending from the posterior corner of the eye down to nearly the shoulder; vomerine ridge present, bearing small teeth; tongue moderately long, emarginated (Figs
Minervarya andamanensis cannot be confused with other known members of the genus Minervarya, except three members of the M. andamanensis group (M. charlesdarwini, M. nicobariensis, and M. muangkanensis). Minervarya andamanensis can be distinguished from M. nicobariensis by its head longer than wide, HL 15.2±1.0 vs. HW 13.9±1.2 (vs. wider, HW 17.5±1.0 vs. HL 16.5±1.1); shank nearly equal to foot, SHL 21.7±1.6 vs. FOL 21.7±1.5 (vs. shorter, SHL 20.9±1.0 vs. FOL 22.1±1.5); presence of outer metatarsal tubercle (vs. absent); and posterior part of thighs light to dark brown with yellowish reticulations (vs. light to dark red with thin black reticulations). Further, it differs from M. muangkanensis (based on
Minervarya andamanensis is endemic to the Andaman Archipelago of India, where we find it to be widely distributed in all the major groups of islands: North and Middle Andamans (North Andaman Is., Landfall Is., East Is., Paget Is., Interview Is., Smith Is., Long Is., North Passage Is., North Reef Is., Baratang Is., and Middle Andaman Is.), South Andamans (South Andaman Is., Boat Is., Alexandra Is., Tarmugli Is., Rutland Is., Neil Is., and Havelock Is.), down to the Little Andaman Island. This species has been observed between elevations of sea level up to nearly 400 m asl (Fig.
Two species of the genus Limnonectes Fitzinger, 1843 are purported to occur in the Andaman Islands. The reports of both L. doriae (
Over the years, both Limnonectes doriae and L. hascheanus have been included in the regional faunal lists of the Andaman Islands (e.g.,
The present study failed to locate the original syntypes (now paralectotypes) of Rana gracilis var. andamanensis that were identified as belonging to Limnonectes hascheanus and L. doriae (SDB personal observation at NHM in 2010; SDB and SG personal observation at ZSI in 2018). Neither did we locate any other specimens referable to these species from this region in potential museums such as ZSIC (Kolkata, India), ZSI/ANRC (Andaman and Nicobar, India), and NHM (London). The additional material reportedly studied by
Morphological variation in skin colouration and markings observed among individuals of Minervarya andamanensis. A–J Dorsolateral views. A SDBDU 2021.4206 (♀). B SDBDU 2021.4207 (♀). C–D Not preserved (♂). E SDBDU 2020.4179 (♀). F SDBDU 2010.4178a (♀). G SDBDU 2019.4011 (♂). H SDBDU 2020.4155 (♂). I Not preserved (♂). J SDBDU 2019.3956 (♂). Photographs: S. D. Biju, G. Gokulakrishnan & Sonali Garg.
Morphological variation observed among individuals of Minervarya andamanensis. A Lectotype (ZSIC 3539 / ZSIC 8539). B–H Dorsal views. B SDBDU 2020.4181 (♀). C SDBDU 2020.4154 (♂). D SDBDU 2021.4207 (♀). E SDBDU 2020.4171a (♀). F SDBDU 2020.4179 (♀). G SDBDU 2020.4155 (♂). H SDBDU 2020.4180 (♂). I–K Ventral views. I SDBDU 2020.4180 (♂). J SDBDU 2020.4154 (♂). K SDBDU 2020.4171a (♀). L Lateral view, SDBDU 2021.4291 (♀). M–N Ventral view of hand, SDBDU 2021.4207 and SDBDU 2000.4179, respectively). O Schematic illustration of foot webbing, SDBDU 2021.4207 (♀). P–Q Ventral view of foot, SDBDU 2020.4179 and SDBDU 2001.4207, respectively. R Posterior view of thigh, SDBDU 2020.4179 (♀). S. Dorsal view of thigh, SDBDU 2021.4207 (♀). Photographs: S. D. Biju.
At the same time, we observed that Minervarya charlesdarwini and M. andamanensis occur sympatrically in most of the reported and surveyed localities. With both the species being extremely variable in dorsal colour and markings, the possibility of L. doriae and L. hascheanus being misidentifications of M. charlesdarwini cannot be ruled out. While describing L. hascheanus from Peninsular Malaysia,
In light of the above and the fact that no recent surveys, especially since the description of Minervarya charlesdarwini, have reported new specimens referable to the two Limnonectes species, except for their mostly unverified inclusion in regional checklists, the occurrence of both L. doriae and L. hascheanus in Andamans should not only be considered erroneous but the two should be excluded from the list of Andaman amphibians to avoid further confusions. It is also interesting that Stoliczka could have collected the enigmatic M. charlesdarwini over a century ago, in 1869. However, we may not know with certainty, unless the discovery of the ‘lost’ specimens from Stoliczka’s collection, or the verification of at least some specimens examined by
The only minervaryan species to be reported from the Nicobar group of the Andaman and Nicobar Archipelago is Minervarya nicobariensis (Stoliczka, 1870). This taxon was originally described as a new variety “var. nicobariensis” of Rana gracilis Wiegmann sensu Günther, 1864 (= Fejervarya limnocharis Gravenhorst, 1829) from “the Nicobars, in the neighbourhood of the Nancowri harbour”. The description was based on “one peculiar young specimen” measuring “1¼th inch” (= 31.75 mm), which was later stated to be ZSIC 2679 by
Since the original description, this taxon has been moved to three currently recognised dicroglossid genera, Limnonectes, Fejervarya, and Minervarya, chiefly owing to the different genus-level reorganisations proposed within the family (e.g.,
Not only do these two species share several unique morphological traits (such as scattered dorsal and lateral tubercles with black spots, presence of discontinuous skin folds on dorsum, upper ⅔rd of tympanum and inner margin of tympanic fold dark brown, absence of prominent markings on groin, and ventral surfaces of hand and foot light grey to blackish-brown) compared to other members of the Minervarya andamanensis group, but also exhibit similarities in being primarily associated with forest habitats and their phytotelm breeding preferences. In view of the surprising phylogenetic position of M. charlesdarwini revealed in the present study, which had alluded researchers for several years, a sister relationship of M. nicobariensis with M. charlesdarwini is likely to be expected, for which a future molecular assessment can provide a conclusive evidence.
Distribution. Minervarya nicobariensis is endemic to the Nicobar Archipelago of India, where we find it to be widely distributed in the central and southern group of islands: Central Nicobar (Bompoka Is., Kamorta Is., Nancowry Is., and Katchal Is.) and South Nicobar (Little Nicobar and Great Nicobar). This species has been observed between elevations of nearly sea level up to 170 m asl (Fig.
Minervarya agricola is one of the most widely distributed species of minervaryan frogs having a distribution across the Indian mainland (from Tamil Nadu, Kerala, Karnataka, Maharashtra, Gujarat, Rajasthan, Punjab, Haryana, Delhi, Uttarakhand, Uttar Pradesh, Chhattisgarh, Andhra Pradesh, Odisha, West Bengal, Bihar, up to Assam), Nepal, Bangladesh, and Sri Lanka (
Morphological variation in skin colouration and markings observed among individuals of Minervarya nicobariensis in Nicobar Islands (all males). A–C Dorsolateral views. A SDBDU 2021.4250. B SDBDU 2021.4249. C SDBDU 2021.4251. D–G Dorsal views. D SDBDU 2021.4251. E SDBDU 2021.4250. F SDBDU 2021.4252. G SDBDU 2021.4249. H–I Ventral views. H SDBDU 2021.4250. I SDBDU 2021.4249. J Lateral view (SDBDU 2021.4249). K Dorsal view of thighs (SDBDU 2021.4249). L–N Posterior view of thighs. L SDBDU 2021.4250. M SDBDU 2021.4249. N SDBDU 2021.4256. O Ventral view of thighs (SDBDU 2021.4249). P Ventral view of hand (SDBDU 2021.4249). Q Ventral view of foot (SDBDU 2021.4249). R Schematic illustration of foot webbing (SDBDU 2021.4249). Photographs: S. D. Biju and G. Gokulakrishnan.
Morphological variation observed among individuals of Minervarya agricola. A–E Dorsolateral views. A Not preserved (♂). B SDBDU 2020.4151 (♂). C SDBDU 2019.3987 (♀). D SDBDU 2019.3986 (♂). E SDBDU 2019.3988 (♂). F Dorsal view, SDBDU 2020.4151 (♂). G–H Ventral view, SDBDU 2020.4151 (♂) and SDBDU 2019.3987 (♀), respectively. I Lateral view, SDBDU 2020.4151(♂). J Posterior view of thigh, SDBDU 2020.4151 (♂). K Dorsal view of thigh, SDBDU 2019.4027 (♀). L Ventral view of hand, SDBDU 2020.4151 (♂). M Ventral view of foot, SDBDU 2020.4151 (♂). N Schematic illustration of foot webbing, SDBDU 2020.4151 (♂). Photographs: S. D. Biju and Sonali Garg.
Distribution. Minervarya agricola is a widely distributed species of South and Southeast Asia, being found in India, Sri Lanka, Bhutan, Nepal, Bangladesh, Myanmar, Thailand, and southern China (
The surprising systematic relationships of Minervarya charlesdarwini and the intertwined taxonomic histories of other minervaryan species in the Andaman and Nicobar Islands provide an opportunity to reflect on the need and importance of dedicated taxonomic studies even in relatively less diverse regions. The Andaman and Nicobar are home to barely 21 recognised species of amphibians. Nonetheless, contrary to the widespread belief that all of the floral and faunal components of this region have affinities with the Indo-Burma and Sundaland, the archipelago houses some unique and endemic species that were previously thought to have shared distributions with neighbouring regions. Despite the fact that many of the endemic species were long known to be fairly common and locally abundant their identities remained ambiguous for decades and centuries; for example, M. andamanensis (
The benefits of molecular data, particularly in aiding rapid resolution of long-standing taxonomic confusions, are shown by many recent amphibian studies (e.g.,
Extensive surveys can also yield additional new taxa and distribution records.
We thank the Department of Environment and Forests, Andaman and Nicobar Islands, India for study permissions and logistic support; Kailash Chandra and Kaushik Deuti (ZSI, Kolkata), and Barry Clarke and David Gower (NHM, London) for access to specimens under their care and museum support to SDB and SG; Gunther Köhler for photograph of Minervarya muangkanensis used in Fig.