THE PEARCE- SELLARDS Series NUMBER 11 Taxonomy of the Neotropical Hylidae htj BERTHA LUTZ NOVEMBER, 1968 TEXAS MEMORIAL MUSEUM / 24TH & TRINITY / AUSTIN, TEXAS W. W. NEWCOMB, JR., DIRECTOR Contents Abstract - 5 Subfamily: Hvlinae Gadow 6 Subfamily: Phvllomedusinae 7 Subfamily: Triprioninae 10 Subfamily; Opisthodelphynae 13 Diagnoses 17 Generic Diagnoses 18 Appendix 22 Bibliography 24 Illustrations FIGURES 1. Possible scheme of relationships of hvlid genera 5 2. Hypothesized scheme of relationships of the Hvlidae ( Phyllomedusinae) 9 3. Hypothesized scheme ofrelationships of the Hylidae (Triprioninae) 11 4. Hypothesized scheme ofrelationships of the Hylidae (Opisthodelphynae) 14 TABLES 1. Genera Hylidarum 8 3 Taxonomy of the Neotropical Hylidae * BERTHA LUTZ ABSTRACT The Hylidae are arciferous, procoelian frogs, generally having maxillary teeth. Presumably derived from bnfonid stock (Noble, 1931), one of the dis- tinctive features of the family is the cartilage intercalated between the penul- timate and the terminal phalanx of the digits, which is claw-shaped and swollen at the base. The digits usually terminate in expanded disks which, together with the intercalary cartilage, subserve the function of climbing. Al- though most of the members of this family are tree frogs, some are aquatic in the adult stage; others are phragmotic, resting upright in cavities of the right size, and plugging the lumen with the head. A number are bromeli- colous, and one or two live in giant bamboos, having water-holding septa. One genus is fossorial. The type genus, Hyla (Fig. 1) is widespread except for a hiatus in the Indo-Malayan, Polynesian, Ethiopian and Madagascan regions. The largest number of species is found in the New World. The genus Nyctimystes, re- stricted to the Papuan Region from the Moluccas to the Louisiade Archi- Fig. 1. Possible scheme of relationships of hylid genera. ° Museu Nacional Rio de Janeiro, Brazil. 5 pelago, has been kept in the family (Zweifel, 1958). The genera Acris and Pseudacris are nearctic (Coin, 1961). All other genera are neotropical. SUBFAMILY: HYLINAE GADOW, 1901 (in part) In Hyla, the sacral diapophyses are generally dilated and most species have odontoids on the vomers. The pupil is generally horizontal and the disks are unusually large. There is some webbing between the digits, at least on the feet. The life history is that usually ascribed to Amirans, i.e. numerous small eggs, aquatic larvae, and non-aquatic adults. A moderate amount of specialization occurs within the type-genus. The neotropical species are apt to form several well-defined groups whose com- ponents are easilv separated from those of other groups and, in life, also from each other. After death they are less easy to separate. H. decipiens Lutz, a verv small species, hangs its spawn on the end of little branches dangling over water; some of its populations have no vomerine teeth. One group of extremely large forms produces a rubbery skin secretion. In other large forms the sharp rudiment of the pollex is protrusible in the males and is used as a weapon. None of these features seems important enough to warrant their separation as a genus, though some subgeneric names might be used. Brocchi (1877) described a genus Plectrohyla with a sharp-pointed pollex- rudiment. This characteristic, also occurring in other species of Hyla, is ac- companied in Plectrohyla by another osteological feature, i.e., the absence of the quadrato-jugals. This and other species may serve as an example of groups for which a subgeneric name might be used. I propose to separate from the type-genus the forms which show a moder- ate degree of specialization, mainly through reduction of some of the generic characters of Hyla. A divergent frog was first proposed as a genus by Tschudi (1838), then by Fitzinger (1843). The name offered by Tschudi, Sphoenorrhynchus, proved to be preoccupied by a stork, and Fitzinger's name, Dryomelictes, was rein- stated by Coin (1961). Before Coin a new name, Sphoenohyla, was proposed at subgeneric level by Lutz & B. Lutz (1938), who did not have the Fitzinger paper. The main difference between Dryomelictes and Hyla lies in the reduc- tion of the maxillary teeth associated with a wedge-shaped snout and the presence of a backward-directed process on the ischium. The adults are hygrophilous; the males call while floating on the water or sitting on leaves in it. At least one species, however, D. orophila, seeks refuge in bromeliads in winter. Another evolutionary line in which there is reduction of structures is also rather short. At present it comprises two neotropical genera which parallel the nearctic hylid genera Acris and Pseudacris. The reduction affects the disks and the digits, hence the frogs are poor climbers. The two nearctic genera also have small disks but they are small slender frogs, whereas the two neotropical ones are heavy and plump. They are Hyloscirtus Peters 6 (1882) and Aplastodiscus Lutz (1950). Aplastodiscus has narrow disks, not wider than the digits, which are also narrow and frail with poorly ossified phalanges. The type-species is montane and lives in the ecotone between forest and open country. It does not climb high, either in nature or in the vivarium. Hijloscirtus hogotensis Peters is similar but shows no trace of an ear. I have not seen it myself. Coin, the last reviewer of hylid genera (1961), maintains both genera, and suggests that Chorophilus cuzcanus Cope may be an Aplastodiscus. This seems probable. Since Cope’s time, Chorophilus has been synonymized with Pseudacris and the Peruvian form certainly does not belong there. This frog is practically unknown and needs to be redefined. The genera discussed in this section are either monotypic or have only a few species, except the nearctic ones which are better known. The nearctic forms illustrate the numeric disproportions among genera which presently exist in the Hvlidae. The type-genus has several hundred species, whereas only a few of the other genera have as many as 10 to 20 forms (see Table 1); most genera are monotypic or contain very few species. The next genus, Amphodus Peters (1872) is aberrant although somewhat parallel to Hyla. I place it alone because it presents a difficult taxonomic problem. Super- ficially, it is very much like a thjla but it has an osteological specialization which consists of pseudo-teeth on the lower jaw and odontoids on the pala- tines and the parasphenoid. Odontoids on these bones recur in other hylid genera but they belong to a series of large casque-headed forms. The pseudo teeth on the lower jaw of Amphodus are merely the unique, saw-edged border of the dentary and the prearticular bones. The genus is composed of three species, all of them small, and all of them strict bromeliad-dwellers. They spawn in leaf-cups and the larvae develop there. One species, A. luteolus Wied, occurs in the bromeliads of the scrub vegetation on the coast of Espirito Santo and Bahia and has been found in a similar location in Pernambuco. I have collected it myself and have received it from others. The type-species A. wuchereri is also from Bahia but it needs to be found again. The third, A. auratus is endemic in Trinidad, British West Indies, where it is limited to the bromeliads on Mount Tecuchi, the highest point of the island. The other lines of specialization go further. There are three main ones, each of them exhibiting increasing divergence in one or more directions from the type-genus. SUBFAMILY: PHYLLOMEDUSINAE MIRANDA-RIBEIRO 1926 (Phvllomedusidae Guenther, 1863) Diagnostic Characters : One of the specialized neotropical hylid groups composed of frogs with vertical pupil, a grasping foot or a tendency toward one, and the habit of spawning out of water but near or above it in rolled-up leaves (Fig. 2). The vertical pupil evidently does not occur by transition. There are 7 Table 1 GENERA HYLIDARUM GENERA NUMBER RANGE SPECIES HYLINAE GADOW, 1901 (in part) Hxjla Laurenti, 1769 100fn) Cosmopolitan, with hiatus Neofropicae : PlectrohijJa Brocchi, 1877 6 Central America, Mexico Aplastodiscus Lutz, 1950 1-2 Brazil, Peru HyJoscirtus Peters, 1882 1 Colombia Dryomelictes Fitzinger, 1843 6 S. Amer., cisandine-cisplatine • Amphodus Peters, 1872 (incertae sedis) 2—3 Brazil, Trinidad, BWI PHYLLOMEDUSINAE MIRANDA-RIBEIRO, 1926 Agalychnis Cope, 1864 10 Mexico, Ecuador, Brazil Phyllomedusa Wagler, 1830 4- 5 S. America Piihecopus Cope, 1866 14—15 S. America, Trinidad, BWI Hylomantis Peters, 1872 1- 2 Brazil Nyctimantis Boulenger, 1882 1 Ecuador TRIPRIONINAE MIRANDA-RIBEIRO, 1926 Osteocephahis Steindachner, 1862 8-10 S. America, cisandine, cisplatine Trachycephalus Tschudi, 1938 4 ± S. America, Antilles Pternohyla Boulenger, 1882 1 Mexico, Arizona Corythomantis Boulenger, 1896 3 Brazil, Venezuela Aparasphenodon Miranda Ribeiro, 1920 1 Brazil Triprion Cope, 1865 1 Mexico into C. America Tetraprion Stejneger & Test, 1891 1 Ecuador Diaglena Cope, 1887 2 Mexico Anotheca Smith, 1939 1 Panama, Vera Cruz, Mexico OPISTHODELPHYNAE n. subf. Fritziana Mello Leitao, 1937 2 SE. Brazil Flectonotus Miranda Ribeiro, 1926 1 SE. Brazil NofothecaBokennann, 1950 3 Brazil, Venezuela, Trinidad Cryptobatrachus Ruthven, 1916 3-4 Hylaea, Andes Gastrotheca Fitzinger, 1843 3-4 S. America, Panama Opisthodelphys Guenther, 1958 10 S. America, Panama Ceratohyh Espada, 1871 6 Hylaea, Panama AMPHIGNATHODONTINAE GUENTHER Amphignathodon Boulenger, 1862 1 Andes, Ecuador Nearctic: Acris Dumeril et Bibron 8 E. of Rocky Mountains Pseudacris Fitz. 12 N. America Papuan: Nyctimantis Stejneger 14 Molluccas to Louisiades neotropical Hylidae with diamond-shaped pupils but they follow another line of specialization. The vertical pupil is correlated with a strictly nocturnal way of life and with a clear-cut separation, in color and texture, between the permanently visible surfaces and those concealed in repose. Even the hand and foot are divided, longitudinally, the color and texture of the outer digits differing from those of the inner, which are hidden when the frog is in a 8 Fig.