An Enigmatic New Scaphiophryne Toadlet from the Rainforests of North-Eastern Madagascar (Amphibia: Microhylidae)
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64 (1): 95 – 102 © Senckenberg Gesellschaft für Naturforschung, 2014. 16.5.2014 An enigmatic new Scaphiophryne toadlet from the rainforests of north-eastern Madagascar (Amphibia: Microhylidae) Achille P. Raselimanana 1, Christopher J. Raxworthy 2, Franco Andreone 3, Frank Glaw 4 & Miguel Vences 5, * 1 Département de Biologie Animale, Université d’Antananarivo, BP 906, Antananarivo 101, Madagascar, and Association Vahatra, BP 3972, Antananarivo 101, Madagascar — 2 American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024-5192 USA — 3 Museo Regionale di Scienze Naturali, Via G. Giolitti, 36, 10123 Torino, Italy — 4 Zoologische Staatssammlung München, Münchhausenstrasse 21, 81247 München, Germany — 5 Zoological Institute, Technische Universität Braunschweig, Mendelssohnstr. 4, 38106 Braunschweig, Germany — * Corresponding author; m.vences(at)tu-bs.de Accepted 21.ii.2014. Published online at www.senckenberg.de/vertebrate-zoology on 30.iv.2014. Abstract A new species of Scaphiophryne is described from north-eastern Madagascar. The new toadlet species is probably at least partly fossorial as can be judged from its large and sharp metatarsal tubercle, and seems to lead a secretive or strictly seasonal life since very few adult specimens were collected despite intensive field surveys in the region. The new species differs from all otherScaphiophryne , among other characters, by the absence of a tarsal tubercle and reminds the genus Paradoxophyla in its strongly marbled ventral pattern on belly and hindlimbs, and by its triangular head shape with pointed snout. Key words Anura; Microhylidae; Scaphiophryne; Scaphiophryne matsoko sp. n.; Marotondrano Special Reserve; tarsal tubercle. Introduction Madagascar harbors an extraordinary diversity of am- endemic clade (VAN DER MEIJDEN et al., 2007), (4) the phibians, with currently about 290 described species, and hyperoliid genus Heterixalus, and (5) the ptychadenid many others (at least 130) still waiting to be described species Ptychadena mascareniensis (GLAW & VENCES, (VIEITES et al., 2009). Over 40 new species have been 2007; CROTTINI et al., 2012). In addition, a frog native to described since 2010. Contrasting with its high species India (Hoplobatrachus tigerinus, belonging to the fam- diversity, the Malagasy amphibian fauna is characterised ily Dicroglossidae) has been introduced to Madagascar by a considerable paucity of families (GLAW & VENCES, (KOSUCH et al., 2001). 2007), represented by five major phylogenetic clades Species-level endemism in Madagascar‘s amphibians (ANDREONE et al., 2005; VIEITES et al., 2009; CROTTINI et is complete if considering the entire island and if ignor- al., 2012): (1) the family Mantellidae which is endemic to ing human introductions (100% of the island‘s amphib- Madagascar and Mayotte, (2) the microhylid subfamily ians naturally only occur in Madagascar), but is also high Dyscophinae, (3) the microhylid subfamilies Cophylinae considering smaller regions within Madagascar. This and Scaphiophryninae which together probably form an high rate of microendemism clearly represents a major ISSN 1864-5755 95 A.P. Raselimanana et al.: An enigmatic new Scaphiophryne toadlet from Madagascar challenge for conservation strategies because it is diffi- Vouchers specimens were euthanized in chlorotone so- cult to establish efficient conservation strategies for nar- lution and fixed in 5% formalin. Subsequently they rowly distributed taxa (KREMEN et al., 2008). The north- were soaked in water to remove formalin before being eastern (NE) portion of Madagascar represents one of the preserved in 70% ethanol. Specimens examined are de- most interesting centers of amphibian diversity and mi- posited in the herpetological collections of the Museo croendemism (e.g., WOLLENBERG et al., 2008b). Factors Regionale di Scienze Naturali, Torino (MRSN), the contributing to this situation might be the heterogeneity Université d’Antananarivo, Département de Biologie of the landscape, and the geographic situation, with con- Ani male (UADBA), and the University of Michigan, nections to the northernmost parcels of the eastern rain- Mu seum of Zoology (UMMZ). Comparative material forest belt, to the Sambirano rainforest, as well as to areas was examined from the Zoologisches Forschungs mu- of transitional and dry forest. seum A. Koenig, Bonn (ZFMK), the Zoologische Staats Despite the intensive biological inventories carried sammlung München (ZSM), and the Zoological Museum out within different forest blocks in NE Madagascar, Amsterdam (ZMA). the species inventory of this area is far from complete, The following measurements were taken with a cali- as indicated by the discovery of many new species over per to the nearest 0.1 mm: SVL (snout-vent length), HW the last 10 years. These include, for example, Boophis (head width at the maxillary rictus), HL (head length, ulftunni, Gephyromantis tahotra, G. ranjomavo, G. sal from the maxillary commissure to the snout tip), ED egy and Blommersia variabilis (ANDREONE et al., 2003; (horizontal eye diameter), END (eye-nostril distance), WOLLENBERG et al., 2008a; ANDREONE et al., 2010; PABIJAN NSD (nostril-snout tip distance), NND (nostril-nostril et al., 2011; GLAW & VENCES, 2011; GLAW et al., 2011). distance), TD (horizontal tympanum diameter), HAL The genus Scaphiophryne, together with Para do xo (hand length, from the carpal-metacarpal articula- phyla, represent the endemic subfamily Scaphiophryninae tions to the tip of the longest finger), FORL (forelimb within the Microhylidae (BLOMMERS-SCHLÖSSER & BLANC, length, from the axil to the tip of the longest finger), HIL 1991). Scaphiophrynines probably form a clade with (hindlimb length, from the cloaca to the tip of the longest the equally Madagascar-endemic Cophylinae (VAN DER toe), FOL (foot length, from the tarsal-metatarsal articu- MEIJDEN et al., 2007; KURABAYASHI et al., 2011) although lations to the tip of the longest toe), FOTL (foot length other studies placed them with African Hoplophryninae including tarsus, from the tibiotarsal articulation to the (PYRON & WIENS, 2011), and they are not particularly tip of the longest toe), IMTL (maximum length of inner species rich: Paradoxophyla currently contains two and metatarsal tubercle). The sex and maturity of preserved Sca phio phryne eight nominal species (GLAW & VENCES, specimens were determined by dissection and gonad ex- 2007), plus two dubious species, S. obscura and S. verru amination. cosa which are probably valid due to nomenclatural pri- ority, but were not yet assigned to any of the known spe- cies. The toadlets of the genus Scaphiophryne are mainly Scaphiophryne matsoko sp. nov. characterised by the morphology of their psammonek- tonic tadpole which is intermediate between the ra- Figs. 1 – 4 noid and the microhylid type (BLOMMERS-SCHLÖSSER, 1975; WASSERSUG, 1984; MERCURIO & ANDREONE, 2006; GROSJEAN et al., 2007, 2009). Sca phio phryne typically re- Holotype. UADBA 29301 (field number APR 6090), probably an produce in lentic, often temporary waters, and deposit a adult male, collected on 28 November 2004 in the Special Reserve large number of small eggs (BLOM MERS-SCHLÖSSER, 1975; of Marotondrano, Mandritsara Fivondronana, Mahajanga Province, VENCES et al., 2002a). Madagascar, – 16.285, 48.81500, 850 m above sea level, by A. P. Our field research in NE Madagascar revealed at sev- RASELIMANANA. eral sites the presence of an undescribed but morphologi- Paratypes. Three specimens, UADBA 29300 and UADBA cally highly distinct species that can be ascribed to the 29302 – 29303 (field numbers APR 6055, 6091 and 6131) with genus Scaphiophryne. In this paper we provide the for- same collection locality and date as holotype (except UADBA mal description of this new species and discuss its pos- 29303 collected on 30 November 2004). UMMZ 191168, adult sible relationships to other scaphiophrynine species. male, from Ambatovaky Special Reserve, Soanierana-Ivongo Faritany, Toamasina Fivondronana, eastern Madagascar, 600 m above sea level, collected by C. J. RAXWORTHY on 22 February 1990, approximately at – 16.74, 49.25. UMMZ 211519, adult male, from a site recorded as Ankarana River, Antalaha Faritany, Materials and Methods Antsiranana Fivondrona, 70 – 100 m above sea level, collected by C.J. RAXWORTHY, ANGELIN RAZAFIMANANTSOA and ANGELUC RA ZA- FIMANANTSOA on 11 January 1993 (coordinates not recorded). MRSN A1849 (FN 6367), juvenile, from Tsararano Forest, Campsite 1, Specimens were collected by opportunistic searches dur- (Antsarahan‘ny Tsararano), Andapa Fivondronana, An tsi ra nana ing day and night and by pitfall traps with drift fences. Faritany (Diego Suarez Province), – 14.90667, 49.68667, on 96 VERTEBRATE ZOOLOGY — 64 (1) 2014 5 December 1996, collected by F. ANDREONE and J. E. RAN DRI- ANIRINA; MRSN A2270, juvenile, from Besariaka Forest, Campsite 1 (Ambinaninimiakamidina), Andapa Fivondronana, Antsiranana Faritany (Diego Suarez Province), at Besariaka forest, Campsite 1, Andapa Fivondronana, Antsiranana (Diégo Suarez) Province, – 14.82167, 49.05417, about 940 m a.s.l., on 28 April 1996, col- lected by J. E. RANDRIANIRINA. Diagnosis. A microhylid toad assigned to the genus Sca phiophryne based on combination of (a) absence of vomerine teeth; (b) rudimentary webbing between toes; (c) large and sharp inner metatarsal tubercle; (d) broad, posteriorly free tongue; (e) apparent dark subgular vo- cal sac. See comments below for a distinction from all other microhylid genera in Madagascar. Distinguished