Wednesday, August 8, 2012

[Herpetology • 1998] The largest lungless tetrapod: a second specimen of Atretochoana eiselti (Amphibia: Gymnophiona: Typhlonectidae) from Brazil

The discovery is reported of a second specimen  of the radically divergent lungless aquatic caecilian  Atretochoana eiselti (Taylor), previously known  only from the holotype. Aspects of the morphology of the second specimen  are described and compared to the holotype, allowing a minimal evaluation of variation within this enigmatic  species.  With a  total  length  of  805 mm, the second specimen is the largest known lungless  tetrapod. Most  of the  distinctive  morphological features reported for the holotype are  true  of the second specimen  also indicating  that the  holotype  is  not  a  'hopeful  monster'.  An  important  exception,  from  the perspective of species  identification, is  variation  in  the  form  of the  pattern  of denticulations about the cloacal disk.  Although precise  locality data  are lacking for both the holotype and  the second specimen,  the latter specimen was  almost certainly collected more recently and from within Brazil.  This justifies  increased expectation  that  this  remarkable  species  is  still  extant  and  that  it  will  be rediscovered. 
Keywords:  Atretochoana, Typhlonectidae, Gymnophiona, Caecilian, lunglessness, Neotropics, Brazil. 

 Nussbaum, Ronald A.; Wilkinson, Mark. 1995. A New Genus of Lungless Tetrapod: A Radically Divergent Caecilian (Amphibia: Gymnophiona). Proceedings of the Royal Society of London Series B Biological Sciences. 261 (1362): 331–339. DOI:10.1098/rspb.1995.0155 .

Wilkinson, M.; Sebben, A.; Schwartz, E.N.F.; Schwartz, C.A. 1998. The largest lungless tetrapod: report on a second specimen of Atretochoana eiselti (Amphibia: Gymnophiona: Typhlonectidae) from Brazil. Journal of Natural History. 32 (4): 617–627. DOI:10.1516/Q417-21HR-6615-7217

Hoogmoed, Marinus Steven; Coragem, Juliano Tupan. 2011. Discovery of the largest lungless tetrapod, Atretochoana eiselti (Taylor, 1968) (Amphibia: Gymnophiona: Typhlonectidae), in its natural habitat in Brazilian Amazonia. Boletim do Museu Paraense Emílio Goeldi : Ciências Naturais. 6 (3): 241–262.