Insights into the feeding behavior of Madagascarophis meridionalis DOMERGuE, 1987, from Isalo, Madagascar

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1 HERPETOZOA 29 (1/2) Wien, 30. Juli hindlimb), which is known as Wolterstorff Index (cf. WOlTERSTORff 1923). This ap - proach, which is comparable to the heeltest, yielded a maximum error rate of 31 % (ARNTZEN & WAllIS 1999: 185). Compared to the error rate of the heel test, which was 65 % in the grown Common frogs tested, it must be concluded that the heel test threshold values cannot be valid, at least for the populations studied where it turned out to be an unreliable method for the identification of Rana temporaria. ACKNOWlEDGMENTS: The underlying work for this paper was made within the framework of a high school thesis (fachbereichsarbeit: Die fersen - probe beim Grasfrosch Rana temporaria (linnaeus, 1758) - Qualität und Aussagekraft als Bestimmungs - merkmal) as a part of the final high school examination passed in 2014 at the St. Karl, Privates Oberstufen - realgymnasium in Volders, Tyrol. The author would like to thank especially the mentoring teacher Guenter KREWEDl (Kematen) for his pleasant supervision and expertise, but also Walter HöDl (Wien) and Heinz GRIllITSCH (Wien) for their help to publish the result of the fieldwork in this short note. REfERENCES: ARNTZEN, J. W. & WAllIS, G. P. (1999): Geographic variation and taxonomy of crested newts (Triturus cristatus superspecies): morphological and mitochondrial DNA data.- Contributions to Zoology, Amsterdam; 68: CABElA, A. & GRIllITSCH, H. (2001): Verbreitung und ökologie der Amphibien und Reptilien: Amphibien; pp In: CABElA, A. & GRIllITSCH, H. & TIE DEMANN, f.: Atlas zur Verbreitung und ökologie der Amphibien und Reptilien in österreich. Auswertung der Herpeto - faunistischen Datenbank der Herpetologischen Samm - lung des Naturhistorischen Museums in Wien. Wien (umweltbundesamt).: , Wien: umweltbundes - amt. GOllMANN, B. & BORKIN, l. & GROSSENBACHER, K. & WEDDElING, K. (2014): Rana temporaria lin - NAEuS, 1758 Grasfrosch; pp In: GROSSEN - BACHER, K. (Ed.): Handbuch der Reptilien und Am - phibien Europas. Band 5/III A, froschlurche (Anura) III A, (Ranidae I). Wiebelsheim (Aula Verlag). land - MANN, A. & fischler, D. (2000): Verbreitung, Be - standssituation und Habitatansprüche von Amphibien im mittleren Tiroler Inntal und angrenzenden Mittel - gebirgsterrassen.- Natur in Tirol, Innsbruck; 8: NöllERT, A. & NöllERT, C. (1992): Die Amphibien Europas. Stuttgart (franckh-kosmos), pp WOl - TERSTORff, W. (1923): Übersicht der unterarten und formen des Triton cristatus laur.- Blätter für Aquarien- und Terrarienkunde, Stuttgart; 34: KEY WORDS: Amphibia: Anura: Ranidae; Rana temporaria; brown frogs; heel test ; morphology, morphometry, identification, field herpetology; The Tyrol, Austria SuBMITTED: November 14, 2014 AuTHOR: Thomas M. HuBER Stainerstraße 22b, 6067 Absam, Austria < thomas.m.huber@tum. de > Insights into the feeding behavior of Madagascarophis meridionalis DOMERGuE, 1987, from Isalo, Madagascar Madagascar has a rich and diverse colubrid snake fauna numbering about 80 currently described species. Although recent years have seen major advances in the understanding of Malagasy snake systematics as well as the description of several new taxa (e.g., NAGY et al. 2003, 2007, 2012; GlAW & VENCES 2007; franzen et al. 2009; GlAW et al. 2007, 2009, 2013, 2014; VIEITES et al. 2010), there is still little knowledge about the behavior or ecology of most spe - cies. The present note provides insights into the feeding behavior of a little-known lamprophiid species endemic to south-western and south-central Madagascar, Madagascar - ophis meridionalis DOMERGuE, The genus Madagascarophis MER - TENS, 1952, comprises four recognized spe - cies (GlAW et al. 2013) of crepuscular and nocturnal snakes with highly varied diets: recorded prey items include frogs, lizards, snakes and birds (CADlE 2003). Mada - gascarophis meridionalis is largely known from the arid spiny forests of south-western Madagascar, but specimens from the Isalo Massif and further east (Andringitra National Park) have also been identified as M. meridionalis, using nuclear and mitochondrial markers (NAGY et al. 2007, 2013). A telemetry study on the spatial ecology of the Rainbow frog, Scaphiophryne gott - lebei BuSSE & BöHME, 1992 (ANDREONE et al. 2013) carried out in the Isalo Massif (fiana - rantsoa Province, Antsohy fivondro nona, Ranohira firaisana) revealed some information on the species interspecific interactions. One of the radio-tracked individuals was consumed by a juvenile M. meridiona - lis [not M. colubrinus (SCHlEGEl 1837), as previously reported; ANDREONE et al. 2013], later captured on 15 february 2011 near Malaso canyon (22 35,49 S; 45 21,44 E) (fig. 1). The specimen is currently preserved at the Parc Botanique et Zoolo gique de Tzimbazaza (Antananarivo, Madagascar) under the provisional code fazc On 12 february 2011, an adult individual of M. meridionalis was observed

2 All_Short_Notes_SHORT_NOTE.qxd :17 Seite HERPETOZOA 29 (1/2) Wien, 30. Juli 2016 fig. 1: Juvenile of Madagascarophis meridionalis DOMERGuE, 1987, captured after consumption of an adult Scaphiophryne gottlebei BuSSE & BöHME, 1992, being radio-tracked. The figure shows the transmitter that was attached to the frog inside the snake s digestive tract. Photo by P. Eusebio Bergò. preying on an adult Mantidactylus sp. aff. femoralis (BOulENGER, 1882) (fig. 2). This is a locally common water-dwelling frog species in Anjofo canyon (Andrianomanero), Isalo Massif (22 22,01 S; 45 21,96 E). The snake was spotted already with half of fig. 2: Madagascarophis meridionalis DOMERGuE, 1987, consuming an adult Mantidactylus sp. aff. femoralis (BOulENGER, 1882) in Anjofo canyon (Andrianomanero), Isalo Massif, Madagascar. A-B the snake swallows the frog head first; C the individual writhes its body to facilitate the passage of the prey to the stomach. Photos by P. Eusebio Bergò.

3 All_Short_Notes_SHORT_NOTE.qxd :17 Seite 29 HERPETOZOA 29 (1/2) Wien, 30. Juli fig. 3: Madagascarophis meridionalis DOMERGuE, 1987, swimming (A) and foraging (B) in a stream in the Namazaha Valley, Isalo Massif, Madagascar. Photos by l. Jasper. the frog body in its mouth. The episode subsequently lasted for about five minutes (from 18:36 to 18:41), before the snake had completely swallowed the frog. On 4 January 2013, at 09:25, another adult individual of M. meridionalis was encountered in Namazaha Valley, also within the Isalo Massif ( S; E, 850 m a.s.l.). The snake was actively foraging within a small rocky stream. upon the first encounter, the animal was entirely submerged and remained underwater for at least 30 seconds, during which time it repeatedly inserted its head between and under rocks in search of prey. When it emerged it continued to move along the

4 106 HERPETOZOA 29 (1/2) Wien, 30. Juli 2016 stream for several minutes with its head above water (fig. 3) until when (perhaps disturbed by our presence) it left the stream and sought refuge under some dense waterside vegetation. It was still present under this vegetation an hour later. The authors presume that the snake was searching for frogs, or perhaps their eggs or tadpoles, because no aquatic lizards are known from this region and these snakes are not known to eat invertebrates. The diurnal, active foraging observed seems unusual in the genus Madagascar - ophis, which is known to be primarily nocturnal or crepuscular (CADlE 2003; GlAW & VENCES 2007). Interesting to note though that the Namazaha valley is a very narrow, steep-sided canyon, and by this time of the morning had not received any direct sunlight. Amongst other Malagasy snakes, Lio - pholidophis sexlineatus (GÜNTHER, 1882) is semiaquatic and Thamnosophis lateralis (DuMéRIl, BIBRON & DuMéRIl, 1854) has also been recorded in water (CADlE 2003; GlAW & VENCES 2007). The present observations confirm the preference of M. meri - dionalis for aquatic habitats and, although the genus Madagascarophis is known to prey on a range of vertebrate groups, in these canyons on Isalo Massif, M. meridionalis may be a specialist predator of frogs, at least in the rainy season (GlAW & VENCES 2007). ACKNOWlEDGMENTS: The authors are in - debted to the university of Antananarivo, Parc Bota - nique et Zoologique de Tsimbazaza (PBZT), the Di - rection des Eaux et forêts, and Madagascar National Parks (MNP) for permission to visit the National Park of Isalo and to conduct research activity (authorization nos. 191/09/MEf/SG/DGf/DCB.SAP/SlRSE of 22. IX.2009, 222/09/MEf/SG/DGf/DCB.SAP/SlRSE of 12.X.2009, and 357/10/MEf/SG/DGf/DCB.SAP/SCB of 17.XII.2010). The team of MNP at Rano hira Isalo was very helpful, especially its director A. Rajaonarivo and our guide Anicet. The fieldwork was possible with the support of the Mohamed bin Zayed Species Con - servation fund, EDGE, Zoological Society of london, Amphibian Specialist Group, Conservation Internatio - nal, Gondwana Conservation and Research, Regione Piemonte, and the Zurich Zoo. G. M. Rosa holds a doctoral scholarship from the fundação para a Ciência e a Tecnologia (fct) (SfRH/BD/69194/2010); A. Crottini is supported by an Investigador fct contract (If/00209/ 2014) under the Programa Operacional Potencial Hu - mano Quadro de Referência Estratégico Nacional funds from the European Social fund and Portuguese Ministério da Educação e Ciência. The authors ac - knowledge the project Genomics and Evolutionary Biology cofinanced by North Portugal Regional Operational Programme 2007/2013 (ON.2 O Novo Norte), under the National Strategic Reference frame - work (NSRf), through the European Regional De - velopment fund (ERDf). REfERENCES: ANDREONE, f. & BERGò, P. E. & MERCuRIO, V. & ROSA, G. M. (2013): Spatial ecology of Scaphiophryne gottlebei in the canyons of the Isalo Massif, Madagascar.- Herpetologica, lawrence; 69 (1): CADlE, J. E. (2003): Colubridae, Snakes; pp In: GOODMAN, S. M. & BENSTEAD, J. P. (Eds.): The natural history of Madagascar; Chicago (The university of Chicago Press). franzen, M. & JONES, J. & RASElIMANANA, A. P. & NAGY, Z. T. & D CRuZE, N. & GlAW, f. & VENCES, M. (2009): A new black-bellied snake (Pseudoxyrhophiinae: Liophidium) from western Madagascar, with notes on the genus Pararhadinaea.- Amphibia-Reptilia, leiden; 30: GlAW, f. & KuCHARZEWSKI, C. & NAGY, Z. T. & HAWlITSCHEK, O. & VENCES, M. (2014): New insights into the systematics and molecular phylogeny of the Malagasy snake genus Liopholidophis suggest at least one rapid reversal of extreme sexual dimorphism in tail length.- Organisms, Diversity & Evolution, Berlin, Heidelberg; 14 (1): GlAW, f. & NAGY, Z. T. & franzen, M. & VENCES, M. (2007): Molecular phylogeny and systematics of the pseudoxyrhophiine snake genus Liopholidophis (Reptilia, Colubridae): evolution of its exceptional sexual dimorphism and descriptions of new taxa.- Zoologica Scripta, Oxford; 36: GlAW, f. & NAGY, Z. T. & KöHlER, J. & franzen, M. & VENCES, M. (2009): Phylogenetic relationships of a new species of pseudoxyrhophiine snake (Reptilia: lamprophiidae: Thamnosophis) suggest a biogeographical link between western and northern Madagascar.- Organisms, Diversity & Evolution, Berlin, Heidelberg; 9: GlAW, f. & VENCES, M. (2007): A field guide to the amphibians and reptiles of Madagascar. Third edition. Köln (M. Vences und f. Glaw Verlags GbR), pp GlAW, f. & VENCES, M. & KuCHARZEWSKI, C. & NAGY, Z. T. (2013): Resolving an enigma by integrative taxonomy: Madagascarophis fuchsi (Serpentes: lamprophiidae), a new opisthoglyphous and microendemic snake from northern Mada - gascar.- Zootaxa, Auckland; 3630 (2): NAGY, Z. T. & GlAW, f. & ANDREONE, f. & WINK, M. & VENCES, M. (2007): Species boundaries in Malagasy snakes of the genus Madagascarophis (Serpentes: Colubridae sensu lato) assessed by nuclear and mitochondrial markers.- Organisms, Diversity & Evolution, Berlin, Heidelberg; 7: NAGY, Z. T. & JOGER, u. & WINK, M. & GlAW, f. & VENCES, M. (2003): Multiple colonization of Madagascar and Socotra by colubrid snakes: evidence from nuclear and mitochondrial gene phylogenies. - Proceedings of the Royal Society, london; (B) 270: NAGY, Z. T. & SONET, G. & GlAW, f. & VENCES, f. (2012): first largescale DNA barcoding assessment of reptiles in the biodiversity hotspot of Madagascar, based on newly de - signed COI primers.- PloS One, lawrence; 7: e VIEITES, D. R. & RATSOAVINA, f. M. & RAN DRI ANIAINA, R.-D. & NAGY, Z. T. & GlAW, f. & VENCES, M. (2010): A rhapsody of colours from Madagascar: discovery of a remarkable new snake of the genus Liophidium and its phylogenetic relationships.- Salamandra, Rhein - bach; 46: KEY WORDS: Reptilia: Squamata: Serpentes; Madagascarophis meridionalis, feeding behavior, prey, ethology, Madagascar

5 HERPETOZOA 29 (1/2) Wien, 30. Juli SuBMITTED: December 15, 2014 AuTHORS: Gonçalo M. ROSA (corresponding author, < >) 1, 2, 3) ; Paolo Eusebio BERGò 4) ; franco ANDREONE 4) ; Angelica CROTTINI 5) ; louise JASPER 6) ; Charlie J. GARDNER 1, 7) 1) Durrell Institute of Conservation and Eco - logy, School of Anthropology and Conservation, uni - versity of Kent. Canterbury, Kent, CT2 7NR, uk 2) Institute of Zoology, Zoological Society of london, Regent s Park, NW1 4RY london, uk 3) Centre for Ecology, Evolution and Environ - mental Changes (CE3C), faculdade de Ciências da universidade de lisboa, Bloco C2, Campo Grande, lisboa, Portugal 4) Museo Regionale di Scienze Naturali, Via G. Giolitti, 36, I-10123, Torino, Italy 5) CIBIO Research Centre in Biodiversity and Genetic Resources, InBIO, universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quin - tas, Nº 7, Vairão, Vila do Conde, Portugal 6 ) BP 639, Toliara 601, Madagascar. 7) WWf Madagascar and Western Indian Ocean Programme Office, BP 738, Antananarivo 101, Madagascar Natrix natrix (linnaeus, 1758), found on the small Islet of Tigani (Central Cyclades, Greece) The European Grass Snake, Natrix natrix (linnaeus, 1758), is one of the most widespread snakes in the Palearctic, occurring from Portugal to Mongolia and from Algeria to Norway (uetz & HOSEK 2014). It prefers wet habitats that range in altitude from sea level up to 3,000 m and is typically found close to water bodies such as lakes, ponds or rivulets (KABISCH 1997). Across the wide distribution of this species, 14 de - scribed subspecies conflict with 16 molecular clades currently recognized (KINDlER et al. 2014). Coloration varies considerably, but the main dorsal background colors are gray, brown and olive-gray whereas the ventral side is commonly whitish, tessellated with black to a variable degree. Very typical is a pair of black occipito-nuchal dots anteriorly bordered by orange to white colored semilunar dots. The dorsal decoration may include regularly arranged black spots and two bright longitudinal stripes. Melanistic or dark colored specimens were frequently reported (KA BISCH 1999). In Greece, N. natrix ranges throughout the mainland, where it is one of the most common snakes and at times occurs in dense populations (KABISCH 1997; VAlAKOS et al. 2008). It is also found on several Ionian and Aegean islands (CHONDROPOu- los 1989; VAlAKOS et al. 2008), always in areas near water (CATTANEO 2001, 2010; BROGGI 2014). The strong aquatic character of the species shapes its diet; N. natrix feeds mainly on amphibians, but has been known to supplement its normal diet with fish (HuTINEC & MEBERT 2011). However, water is a rare commodity on Mediterranean islands, especially on those located in the Aegean Sea (CATSADORAKIS & PARAGAMIAN 2007; VERVuST et al. 2013). As a result, the Grass Snake is absent from many small islands, which often lack water sources (BROGGI 2008, 2009). In the Cyclades, wherever it occurs, its populations are small and the last individuals are imperiled (e.g., in Milos, BROGGI 2000), like the majority of the hydrophilic species in the Archipelago, by the anthropogenic exploitation of freshwater resources (BROGGI 2012; BROGGI & GRIllITSCH 2012). In summer 2014, the authors found N. natrix on the small, dry islet of Tigani, off Paros, which is the first ophidian record for that islet. Tigani is situated between two larger islands, Paros and Antiparos (1.6 km SW of Paros Island, N, E) and belongs to the three-islet cluster called Panteronissia (fig. 1A). Tigani has an area of 0.08 km 2 and is very dry and flat with sparse patches of low, scrubby vegetation. Previous surveys had confirmed the presence of Mediodactylus kotschyi (STEIN- DACHNER, 1870) but no other reptiles or amphibians had been found on the island. The encounter with the snake occurred on 8 June 2014, during an island-wide herpetological survey. It was a warm, sunny eve - ning (24 C), with a few scattered clouds. At 18:45 h, after being on the island for only ten minutes, the authors saw a dark snake dart into a bush. As no snakes had been recorded previously on the island, the specimen was caught, preserved in alcohol and later added to the Herpetology Collection of the Yale university, Peabody Natural His - tory Museum (specimen number YPM HERR ). The snake was a melanistic, non-gravid adult female, (Pholidosis features: keeled dorsal scales, seven super-