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Type: Article
Published: 2019-05-09
Page range: 377–388
Abstract views: 300
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The subterranean Aenigmachanna gollum, a new genus and species of snakehead (Teleostei: Channidae) from Kerala, South India

Department of Life Sciences, The Natural History Museum, London, SW7 5BD, United Kingdom
School of Ocean Science and Technology, Kerala University of Fisheries and Ocean Studies (KUFOS), Kochi 682 506, India.
Indian Institute of Science Education and Research (IISER), Dr. Homi Bhabha Road, Pashan, Pune 411 008, India Zoo Outreach Organization, No. 12 Thiruvannamalai Nagar, Saravanampatti-Kalapatti Road, Coimbatore 641 035, India
Department of Fisheries Resource Management, Kerala University of Fisheries and Ocean Studies (KUFOS), Kochi 682 506, India
Western Ghats-Sri Lanka biodiversity hotspot relict lineages laterite aquifer Pisces


Aenigmachanna gollum, new genus and species, is described from Kerala, South India. It is the first subterranean species of the family Channidae. It has numerous derived and unique characters, separating it from both the Asian Channa Scopoli and the African Parachanna Teugels & Daget. Uniquely among channids, A. gollum has a very slender (maximum body depth only 11.1–11.3% SL), eel-like body (head length 20.8–21.6% SL), large mouth (jaw length 60.4–61.1 % HL), 43–44 anal-fin rays, 83–85 scales in a lateral series, an unusual colour pattern and it lacks pored lateral-line scales on the body and body buoyancy. In addition, it is distinguished by its DNA barcode sequence, which is 15.8–24.2% divergent from other species of the family Channidae. Morphological modifications usually associated with a subterranean life, such as reduction of eyes and enhancement of non-visual senses (taste, smell, mechanosensory systems) are absent in A. gollum. However, it shares with subterranean fishes a slight reduction of its pigmentation in comparison to epigean channids.


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