AMERICAN MUSEUM Novitates PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, N.Y. 10024 Number 2723, pp. 1-14, figs. 1-10 February 26, 1982 A New Montane Microhylid Frog from Papua New Guinea, and Comments on the Status of the Genus Aphantophryne RICHARD G. ZWEIFEL1 AND ALLEN ALLISON2 ABSTRACT Discovery of an undescribed, ground-dwelling these are ones common to many microhylid species of the largely scansorial genus Cophixalus species of similar ground-dwelling habits and do led to the re-evaluation of the monotypic genus not necessarily indicate closeness of relationship. Aphantophryne to see if this genus, presently Evaluation of previously unstudied features of the synonymized within Cophixalus, should be re- anatomy of C. pansus does not support revival of vived to accommodate its terrestrial type species, Aphantophryne either as a monotypic genus or to C. pansus, and the new form. The two species include the new species. The latter is described share some presumably derived features, but as Cophixalus sphagnicola, new species. INTRODUCTION In 1969 Zweifel collected four individuals tion of Allison's ecological studies by pro- of a small, ground-dwelling and apparently viding a name for the undescribed species; unnamed microhylid atop Mount Kaindi, and to investigate whether there is sufficient Morobe Province, Papua New Guinea. The justification for reviving the genus Aphan- habitus of these frogs was sufficiently like tophryne Fry " 1916" [1917] to accommodate that of montane Sphenophryne that he set both its type species (presently assigned to them aside for later consideration in the Cophixalus) and the new frog described course of a proposed revision of that genus. herein. Later, Allison conducted an extensive eco- logical study of this species. He submitted METHODS specimens to Mr. James Menzies, who de- Standard measurements were made and termined that the species has the skeletal utilized in generating ratios used to compare characteristics of the genus Cophixalus rath- proportions: body length, from snout to vent er than of Sphenophryne. The present paper (SV); length of tibia, from heel to outer side has two purposes: to facilitate the comple- of flexed knee (TL); distance from anterior I Curator, Department of Herpetology, American Museum of Natural History. 2 Assistant Director, Wau Ecology Institute, Wau, Papua New Guinea. Copyright © American Museum of Natural History 1982 ISSN 0003-0082. / Price $2.28 2 AMERICAN MUSEUM NOVITATES NO. 2723 edge (corner) of eye opening to center of ex- (1934). Zweifel recognized that this squat, ternal naris (EN); internarial distance, be- short-legged terrestrial frog with rounded toe tween centers of external nares (IN); head tips differed from typical Cophixalus, which width, at jaw articulation (HW); diameter of are scansorial frogs with expanded digital orbit, measured between anterior and pos- tips, but he preferred not to revive a mono- terior edges of eye opening (Eye). Measure- typic genus on these grounds alone, so he ments, expressed in millimeters, were made referred pansa to the genus Cophixalus and, with vernier calipers or ocular micrometer. hence, Aphantophryne to the synonymy of Statistics are given in the format: mean + Cophixalus, where it has remained. The dis- standard error of mean (range). covery of a new terrestrial, montane species somewhat resembling C. pansus calls for ACKNOWLEDGMENTS comparison between the two and with other This research utilized specimens deposited Cophixalus to determine if revival of Aphan- in the American Museum of Natural History, tophryne may be warranted. New York (AMNH), the Bernice P. Bishop Cophixalus was one of five genera of Museum, Honolulu (BPBM), and the Aus- sphenophrynine microhylids recognized by tralian Museum, Sydney (AM). We are Parker (1934), who diagnosed them on the grateful to Dr. Alan A. Ziegler (BPBM) and basis of characteristics of the pectoral girdle. Dr. Harold Cogger (AM) for their coopera- The five formed a graded series distinguished tion. Zweifel's participation in the R/V Alpha by the reduction and loss of ventral elements Helix Expedition in 1969, supported by the of the girdle: Sphenophryne (girdle com- National Science Foundation, contributed plete); Oreophryne (clavicle reduced); Mi- importantly to the study. Part of the research crobatrachus (clavicle supposedly lost); Co- was carried out while Zweifel was a Visiting phixalus (clavicle and procoracoid lost); Curator in the Australian Museum. Aphantophryne (clavicle, procoracoid and, supposedly, sternal plate lost). Several STATUS OF Aphantophryne changes in the generic level taxonomy have Fry ("1916" [1917]) described the genus taken place since Parker's revision. Zweifel and species Aphantophryne pansa on the (1956) referred Aphantophryne to the syn- basis of six specimens taken at an elevation onymy of Cophixalus, and later (1971) re- of 3719 m. (12,200 ft.) in the Owen Stanley defined the Sphenophryninae, transferring Mountains of British New Guinea (now Pa- the genus Genyophryne to it. Tyler (1978) pua New Guinea). The principal feature disposed of Microbatrachus as probably thought to be diagnostic of the new genus based on a juvenile Sphenophryne. Menzies was the lack of a sternal plate. Parker, in his and Tyler (1977) removed the genera Co- revision of the Microhylidae (1934), recog- piula and Choerophryne from the synonymy nized Aphantophryne as a monotypic genus, of Cophixalus. relying on Fry's description in the absence of specimens to examine. Loveridge (1948) FEATURES OF Cophixalus pansus referred Aphantophryne to the synonymy of PERTINENT TO GENERIC STATUS Asterophrys after examining (but not dis- GENERAL MORPHOLOGY: The features of secting) one of Fry's paratypes, and without morphology that impart to C. pansus an ap- reference to the nature of the pectoral girdle. pearance rather different from other Cophix- With relatively fresh material available, alus are ones common to ground-dwelling Zweifel (1956) determined that the type microhylids of several genera: short hind species does possess a sternal plate and oth- legs, narrow toe tips, broad head, small eyes. erwise has the skeletal characteristics of the Leg length of pansus is the shortest relative genus Cophixalus3 as diagnosed by Parker to body length of any Cophixalus. No other 3See Menzies, Tyler, and Zweifel (1980) for the use Cophixalus has digits with no trace of disc of this generic name. development and no trace of terminal 1982 ZWEIFEL AND ALLISON: MICROHYLID FROG 3 A B FIG. 1. Left hands of Cophixalus pansus (A) and C. sphagnicola (B) in palmar aspect. Scale lines marked in mm. grooves (fig. 1A). The terminal phalanges bear what we assume to be vestiges of the T- shaped extensions of scansorial species (fig. 2D). Relative head width and relative eye size are very nearly at the extremes for the genus in pansus. VOMERINE BONES: The shape of the vo- mers may be diagnostic of microhylid genera (Zweifel, 1972; Menzies and Tyler, 1977), but that of pansus does not differ signifi- A B cantly from that of more typical Cophixalus (fig. 3D). SACRAL VERTEBRA: The sacral vertebra of pansus has the diapophyses relatively little expanded. In this respect it differs slightly if at all from scansorial species of Cophixalus (fig. 4). PECTORAL GIRDLE: The sternal plate of pansus is weakly developed compared with A a other Cophixalus. Specimens of other C D species cleared and stained with Alizarin Red often show calcified tissue in the basal of the but no calcification is FIG. 2. Terminal phalanges of third fingers to part sternum, show relative development of T-shaped process- present in a specimen of pansus. In other es. A. Cophixalus verrucosus, a scansorial spe- respects the girdle is like other Cophixalus. cies. B. Copiula sp., a genus of ground-dwelling Fry's ("1916" [1917]) impression of the dis- species, formerly referred to Cophixalus. C. Co- tinctness of the pectoral musculature of pan- phixalus sphagnicola. D. C. pansus. Scale lines sus was accurate within the limited context marked in 0.25 mm. increments. 4 AMERICAN MUSEUM NOVITATES NO. 2723 A A C D :4 -.1 010 "'.j .j G .0 .1 B FIG. 3. Vomers of right side in ventral aspect. A. Cophixalus parkeri, a scansorial species. B. Copiula sp. C. Cophixalus sphagnicola. D. C. pansus. Stippled areas represent cartilage asso- ciated with vomers and sphenethmoids. Scale lines marked in 0.5 mm. increments. of material available to him, but he had no other Cophixalus for comparison. C THROAT MUSCULATURE: Variation in throat musculature is assuming significance FIG. 4. Sacral vertebrae in dorsal aspect. A. in assessing relationships among frogs (Ty- Cophixalus riparius, a scansorial species. B. C. ler, 1971, 1972, 1979; Emerson, 1976). The sphagnicola. C. C. pansus. Scale lines marked in superficial mandibular musculature of C. mm. pansus (fig. 5) is basically similar to that of other microhylids (Tyler, 1979, fig. 4:8; sus than in several other Cophixalus dis- Emerson, 1976, fig. 5): well-developed inter- sected. In these latter species the muscle hyoideus, intermandibularis (with a single may be represented only by fibers distally supplementary slip) and submentalis (inter- along the mandible, hidden by the interman- mandibularis anterior) muscles. dibularis. If the intermandibularis is loos- In pansus there is a fairly sturdy muscle ened medially and reflected, the muscle in (imand d., in fig. 5) lying dorsal to the inter- question reflects with it and may not be rec- mandibularis, between the main body of the ognized. intermandibularis and the lateral geniohyoi- What presumably is the homologous mus- deus. It originates on the mandible and in- cle is well developed in Copiula, reaching serts along with the intermandibularis in the essentially to the median raphe, but is com- region of the median raphe; part of the mus- pletely hidden by the intermandibularis. cle is visible without reflecting the interman- Emerson (1976, fig. 4) illustrates and notes dibularis or its accessory slip.