Mantidactylus betsileanus (Boulenger, 1882)

Andreone, F., Glaw, F., Nussbaum, R. A., Raxworthy, C. J., Vences, M. & Randrianirina, J. E., 2003, The amphibians and reptiles of Nosy Be (NW Madagascar) and nearby islands: a case study of diversity and conservation of an insular fauna, Journal of Natural History 37 (17), pp. 2119-2149 : 2147

(4) Mantidactylus betsileanus . The presence of M. betsileanus on Nosy Be as quoted by Blommers-Schlösser and Blanc (1991) is apparently corroborated by two voucher specimens housed in Paris (both adult females). Colour pattern of MNHN 1975.584 (SVL 38.8 mm) is largely faded, but the main characters are still recognizable. There is only a poorly marked light spot on the snout tip, and no distinct dark and light crossbands on the upper lip. The tibiotarsal articulation reaches the anterior eye corner when the hindlimb is adpressed along the body. Webbing on toes 4 and 5 is 4i/e (2), 5 (0.5). In MNHN 1962.877 (SVL 39.5 mm), a broad light vertebral band spans to the snout tip; however, the snout tip does not show a distinct white spot, only a slight light continuation of the vertebral band. Tibiotarsal articulation reaches anterior eye corner. Webbing, as far as recognizable, is similar to that of MNHN 1975.584. By general aspect and the described characters, both specimens clearly fit into the variation of typical M. ulcerosus , while M. betsileanus specimens are mostly smaller and have longer hindlimbs. M. ulcerosus generally has a more extended webbing (Blommers-Schlösser and Blanc, 1991), but in several ZFMK specimens of M. ulcerosus the webbing approaches the state of the MNHN specimens (e.g. ZFMK 52667, an adult female). The records of M. betsileanus on Nosy Be are thus due to confusion with M. ulcerosus ; we consider M. betsileanus as absent from Nosy Be, as well as probably from north-western and northern Madagascar.