A New Species of Cophixalus (Anura: Microhylidae) from Misima Island, Papua New Guinea1
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A New Species of Cophixalus (Anura: Microhylidae) from Misima Island, Papua New Guinea1 Stephen J. Richards2,3 and Paul M. Oliver2 Abstract: Cophixalus misimae Richards & Oliver, n. sp., is described from low- altitude rain forest on Misima Island, Louisiade Archipelago, Papua New Guinea. It is a small (males 15.5–16.1 mm, females 19.3–19.6 mm) terrestrial species with a visible tympanum, a snout that is distinctly truncate in dorsal view, unwebbed toes, a dark brown lateral stripe, and a call consisting of a train of high-pitched pulses. It is the third species of Cophixalus known from the Lou- isiade Archipelago and is currently known only from Misima Island. The microhylid genus Cophixalus is one be endemic to Sudest (Tagula) Island. One of the most ubiquitous components of the other species (C. verrucosus) with a broad dis- eastern New Guinea frog fauna (Zweifel and tribution on mainland Papua New Guinea is Tyler 1982, Kraus and Allison 2000). Despite known from the nearby D’Entrecasteaux Is- their abundance in many areas (e.g., Simon lands. In the course of fieldwork on Misima 1983) the genus remains poorly studied, with Island S.J.R. collected a series of small terres- no comprehensive taxonomic treatment in trial Cophixalus that could not be assigned to existence. Recent surveys have documented any of these three species or to any other rec- a number of new Cophixalus species (e.g., ognized Cophixalus. These frogs are herein Richards 2002), and five new taxa were de- described as a new taxon. scribed between 2000 and 2003 (Kraus and Allison 2000, Jones 2002, Gu¨nther 2003). These studies increased the number of de- materials and methods scribed in New Guinea to 21 Cophixalus Upon collection, specimens were fixed in (Frost 2004). An additional 14 species of Co- 10% formalin and subsequently stored in are known from northeastern Austra- phixalus 70% ethanol. Measurements (to 0.1 mm) lia (Zweifel 1985, Hoskin 2004). were made with dial calipers and a micro- The Louisiade Archipelago is a series of scope fitted with an ocular micrometer and continental islands extending in a southeast- follow Zweifel (1985) and Zweifel and Parker erly direction from the southeastern tip of (1989). They were of snout-vent length (SV ), mainland New Guinea. Two species of Co- tibia length (TL), arm length (AL), head ( and ) are phixalus C. aimbensis C. tagulensis width at the angle of the jaws (HW ), head known from this region, and both appear to length as a straight-line distance from angle of jaws to tip of snout (HL), eye diameter 1 The South Australian Museum board, the Mark (EYE), internarial distance (IN), eye-naris Mitchell Foundation, and the Winifred Violet Scott Es- distance (EN), horizontal diameter of tym- tate provided funding assistance to S.J.R. During prepa- panic membrane (EAR), width of third finger ration of the manuscript S.J.R. was supported by a grant disk at right angle to digital axis (3FD) and from Conservation International. Manuscript accepted 2 width of penultimate phalanx of third finger June 2006. 2 Vertebrates Department, South Australian Museum, (3FP), width of first finger disk (1FD) and North Terrace, Adelaide, South Australia 5000, Australia. first phalanx (1FP), and of fourth toe disk 3 Correspondence (phone: þ61 8 8207 7473; fax þ61 (4TD) and fourth toe phalanx (4TP), as for 8 8207 7222; e-mail: [email protected]). third finger. One specimen of the new species was cleared and stained using the method of Pacific Science (2007), vol. 61, no. 2:279–287 Dingerkus and Uhler (1977). : 2007 by University of Hawai‘i Press Advertisement calls from a single male All rights reserved were recorded with a tape recorder (Sony 279 280 PACIFIC SCIENCE . April 2007 TCM 5000EV ) and microphone (Sennheiser ME66). Eight calls were analyzed using a sound analysis program (AVISOFT SAS-Lab Pro). Temperature adjacent to the calling male was measured with a quick-reading thermometer (Miller & Weber). Specimens are deposited in the South Australian Mu- seum (sama), Adelaide, and the Natural Sciences Resource Centre of the University of Papua New Guinea (upng). Other speci- mens examined were from the following in- stitutions: amnh, American Museum of Natural History, New York; bm, Natural His- tory Museum, London; bpbm, Bernice P. Bishop Museum, Honolulu; mcz, Museum of Comparative Zoology, Harvard; and msng, Museo Civico di Storia Naturale Genova, Genoa. Locality coordinates for the new species use the Global Positioning System datum WGS84. taxonomic treatment Cophixalus misimae Richards & Oliver, n. sp. Figures 1, 2A, 3 holotype. sama R60286, adult male, 8 Figure 1. Cophixalus misimae Richards & Oliver, n. sp. A, November 2002, from ‘‘Fill 3 Forest,’’ 200– Lateral view of head of holotype (sama R60286), scale bar ¼ 5 mm; B, plantar surface, and C, palmar surface of 250 m above sea level (asl), Misima Mine paratype (sama R60287), scale bar ¼ 2.5 mm. Site (152 47.761 0 E, 10 39.5400 S), Misima Island, Louisiade Archipelago, Milne Bay Province, Papua New Guinea, collected by on tip of snout absent (present in most S. Richards. Copiula), and supplementary slip of m. inter- paratypes. upng 9969, adult male, 10 mandibularis narrow, directed anterome- November 2002, and upng 9970, adult fe- dially, inserting upon the fascia of the m. male, 1 November 2002, same locality as submentalis (versus supplementary slip of the holotype; sama R60287, adult male, 5 No- m. intermandibularis more or less transverse, vember 2002, and sama R60288, adult female, with a broad insertion onto the median raphe 4 November 2002, both from ‘‘North Dump of the m. intermandibularis in Copiula [Bur- Rainforest,’’ 250–300 m asl (152 47.8760 E, ton 1984, 1990]); (4) fifth toe shorter than 10 39.8480 S); sama R60289 (cleared and the third (longer in Albericus), m. depressor stained), adult male, 16 October 2003, Boma mandibulae arising primarily from a broad Village (152 47.064 0 E, 10 39.090 0 S), all origin on dorsal fascia, and otic ramus of specimens collected by S. Richards. squamosal bone short (versus most of origin diagnosis. The new species is a Cophix- of m. depressor mandibulae arising from otic alus based on the following combination of ramus, with a very much smaller origin from characters: (1) jaws eleutherognathine and dorsal fascia, and otic ramus of squamosal clavicles and all other prezonal elements of elongated in Albericus); and (5) toes with ter- the pectoral girdle absent; (2) snout not elon- minal disks bearing circummarginal grooves, gate (as in Choerophryne); (3) translucent pad and relatively long hind limbs (TL/SV 0.52– Cophixalus misimae, n. sp., from Misima Island . Richards and Oliver 281 0.56) (versus disks absent and tibiae short shriveled, in life rounded and at least twice [TL/SV < 0.37] in Aphantophryne [Zweifel as wide as penultimate phalanx. All disks and Parker 1989]). with circummarginal grooves. Cophixalus misimae can be distinguished In preservative, dorsum pale grayish brown from all congeners by the following combina- with numerous tiny, dark brown maculations, tion of characters: (1) small size (maximum eyelid distinctly darker. Ventral ground color 19.6 mm); (2) tympanum distinct; (3) dark yellowish off-white, with numerous scattered, brown lateral band extending from tip of tiny brown spots of various density. Areas snout to approximately two-thirds distance with highest density of spotting appear between fore and hind limbs; (4) snout prom- brown. Throat dark brown with scattered inent, protruding in lateral view, tip distinctly small, light spots. A pair of distinct dark spots truncate in dorsal view; (5) loreal region dorsally above inguinal region, few smaller steep, nearly vertical; (6) distinct dark brown brown flecks between these large spots and spot above inguinal region; (7) toes with urostyle. Dark brown U-shaped marking moderately enlarged, rounded disks and with- around ventral edge of vent, sharply demar- out webbing; (8) fingers 2–4 with moderately cated against dorsal coloration but grading enlarged disks, first finger not markedly re- into ventral coloration and extending along duced, with a small but distinct terminal tibiae. Broad, dark brown, lateral band ex- disk; (9) advertisement call a long train of tends from tip of snout approximately two- pulses lasting up to 5 sec. thirds of the distance between fore and hind description of holotype. Measure- limbs, sharply demarcated against dorsal col- ments are presented in Table 1. Adult male oration but grading into ventral coloration with vocal slits. Body slender, head moder- through interdigitating areas of dark brown ately narrow (HW/SV ¼ 0.36). Snout promi- and yellowish off-white. Arms and legs with nent, distinctly protruding in lateral view; same grayish brown dorsal and yellowish off- narrowing markedly anterior of eyes with dis- white ventral coloration as body. Lateral sur- tinctly truncate tip in dorsal view. Canthus face of arms with a number of longitudinally rostralis rounded but prominent, straight oriented dark brown spots, brown spotting with slight indentation posterior of nostrils. becoming more dense along forearm; hands, Loreal region slightly concave, near vertical; fingers, and lower limbs extensively spotted labial region vertical. Internarial distance with dark brown. Legs dorsally uniformly greater than distance from external naris to yellowish brown, laterally with a number of eyes (EN/IN ¼ 0.81). Eyes moderately large longitudinally oriented dark spots, ventrally (EYE/SV ¼ 0.14). Tympanum half diameter heavily spotted with brown, density of spot- of eye (EAR/EYE ¼ 0.55), conspicuous with ting increasing distally. well-defined tympanic annulus; tongue ovoid. variation. Measurements of the type Supratympanic, posttympanic, and dorsolat- series are presented in Table 1. Females are eral folds absent. In life dorsum and upper larger than males; this size dimorphism is typ- portion of hind limbs smooth with scattered ical of the genus (Zweifel 1962, 1979), and in low tubercles.