24 Accepted by M. Vences: 4 Aug. 2008; published: 3 Nov. 2008 ZOOTAXA ISSN 1175-5326 (print edition) ISSN 1175-5334 (online edition) Copyright © 2008 · Magnolia Press Zootaxa 1921: 24–34 (2008) www.mapress.com/ zootaxa/ Rediscovery of a long known species, Ixalus lateralis Anderson, 1871 L. NZANO HUMTSOE 1 , SABITRY BORDOLOI 1 , ANNEMARIE OHLER 2,3 & ALAIN DUBOIS 2 1 Resource Management and Environment Division, Institute of Advanced Study in Science and Technology, Paschim Boragaon, Guwa- hati-781035, Assam, India 2 Muséum National d’Histoire Naturelle, Département de Systématique et Evolution, USM 602 Taxinomie et Collections, 25 rue Cuvier, 75005 Paris, France 3 Corresponding author. E-mail: ohler@mnhn.fr Abstract The genus Leptolalax Dubois, 1980 is for the first time reported from India. The nomen Ixalus lateralis Anderson 1871, created for a specimen from an unknown type locality, probably in North-East India, is applied to this species. A neotype is designated to stabilize the taxonomic status of this nomen and to fix a precise type locality. Key words: Amphibia, Megophryidae, Ixalus lateralis, neotype Introduction In Günther’s (1864) Reptiles of British India, the Asian representatives of the family Pelobatidae, which now- adays correspond to the Megophryidae of most authors, only counted two species: Megophrys montana Kuhl & Van Hasselt, 1822 and Xenophrys monticola Günther, 1864. The latter was a taxon including various spe- cies of the genus Xenophrys Günther, 1864 as currently recognized (Delorme et al. 2006). Beside these nom- ina, Bombinator sikimmensis Blyth, 1855, a member of Scutiger Theobald, 1868 and Ceratophryne nasuta Schlegel, 1858, then considered a synonym of Megophrys montana, were coined for this family until the 1870ies. Anderson (1871: 29) described the species Ixalus lateralis on a single specimen without type locality. This specimen was found in a jar in the collection of the Indian Museum of Calcutta together with a specimen of Xenophrys monticola. Anderson gave a description, according to the standards of the time. The nomen thus was based on a unique specimen, the holotype by monotypy. In 1879, in the Results of the Yunnan expedition, Anderson reported the collection of several specimens of this species and gave a figure (plate 78, fig. 5) of one of them. Anderson (1879: 844) discussed morphological differences between these specimens and the holotype of Ixalus lateralis. Thus the specimens mentioned and figured in 1879 are different from the holotype and neither their characters nor their collection locality are stringent for establishing the identity of Ixalus lateralis. Sclater (1892: 33) listed the specimen ZSI 10967 in the Calcutta Museum as the holotype of Ixalus later- alis, but this specimen was not traced by Chanda et al. (2000) in this collection, and there exists no published evidence that any author examined this specimen after Anderson (1879). This holotype being unavailable, subsequent authors based their allocation of the nomen on the figure on plate 78 of Anderson (1879). The fig- ures of this book are not of excellent quality, as body shapes of frogs figured are not natural. Thus the identity of this nominal species has been a subject of discussion since.