Table 2.--Variation in Color Pattern in Hyla microcephala underwoodi
PopulationNShanksInterorbital barDorsolateral stripeScapular markingsSacral markingsBarsFlecksPresentAbsentGroinSacrumX)(][Other/\/ \OtherOaxaca: Donají-Sarabia27225270027234007614Tabasco: Teapa-Villahermosa5546955005553200191123Guatemala: La Libertad51510510173445600161421Guatemala: Finca Chamá32320320032320002624Guatemala: Puerto Barrios313103101417230446421Honduras: Lago Yojoa131301309432352110Nicaragua: La Cumplida564412542134311358201937Nicaragua: Tipitapa10100100820532037Nicaragua: Santo Thomás10100100823070055Costa Rica: Tenorio-Tilarán120126675001200012Costa Rica: Las Cañas-Liberia3821[A]1534425130111980038Costa Rica: Esparta322662933020014180032[A]Longitudinal stripes present in two specimens.When this frog is active at night its dorsum is pale yellow; faint flecks are present in some individuals. The white dorsolateral line usually is evident in the tympanic region, but in many individuals a dorsal pattern of lines and other marks is not evident. By day the dorsum changes to yellowish tan or pale brown with dark brown or reddish brown markings (Pl. 13). The venter is white, and the vocal sac in breeding males is yellow. The iris is pale bronze with a brown tint anterior and posterior to the pupil.Remarks.—Hyla microcephala underwoodihas had a confused nomenclatural history. The taxon was first namedHyla microcephalaby Boulenger (1898); this name was preoccupied byHyla microcephalaCope (1886). Cole and Barbour (1906) and Kellogg (1932) used the nameHyla phlebodesStejneger (1906) for specimens of this frog from México. Dunn (1931, 1933, 1934) applied the nameHyla underwoodito Panamanian specimens that we identify asHyla phlebodes. Smith (1951) namedHyla microcephala martinifrom southern México and Guatemala and considered the northern populations to represent a subspecies distinct from the Costa RicanHyla microcephala underwoodi, despite the fact the Stuart (1935:39) stated that comparisons of specimens from El Petén, Guatemala, with the holotype ofHyla underwoodishowed only trivial differences.Much of the confusion regarding the nameHyla underwoodistems from the illustration given by Boulenger (1898:pl. 39, fig. 3) and reproduced by Taylor (1952:892), which shows a frog having a unicolor dorsum, dorsolateral white lines, and dark flanks. This pattern is in marked contrast to the pattern seen in most preserved specimens, which have the dorsum variously marked by dark brown lines or irregular marks. Smith (1951:185), in his description ofHyla microcephala martinifrom southern México, consideredH. underwoodito be a subspecies ofH. microcephalathat lacked dorsal dark markings.Data accumulated in 1961 through field studies by the senior author at the type locality, Bebedero, and other localities in Guanacaste and Puntarenas provinces in Costa Rica provide a reasonable explanation of the differences in color pattern. As noted in the preceding description of this subspecies, at night the dorsal markingsare not evident in many living individuals, whereas by day the dorsal markings are prominent. Most collectors prepare their specimens by day; consequently the majority of specimens have a pronounced dorsal pattern. Of the frogs collected in Costa Rica in 1961, some specimens were preserved at night; others from the same series were preserved by day. The differences are striking. In those preserved at night, dorsal markings are faint, if present at all. Some specimens closely match the figure given by Boulenger (1898).It is extremely doubtful if the frog described and illustrated by Boulenger could be associated with eitherHyla phlebodesorH. microcephala microcephala. Individuals of the former species lack a dorsolateral white line and always have some dorsal markings evident at night; furthermore,H. phlebodesis not known to occur on the Pacific lowlands.Hyla microcephala microcephalaoccurs farther southeast. Since there is no reason to doubt the type locality ofH. underwoodi, since specimens from the area around the type locality that have been preserved at night are like the holotype in pattern, and since the characteristics of the populations of the frogs in Guanacaste are the same as, or gradually blend into those of, populations in northern Central America and southern México, the frogs from throughout the entire range can be referred to one taxon, the earliest name for which isHyla underwoodiBoulenger, which herein is considered to be a subspecies ofH. microcephalaCope.Distribution.—Hyla microcephala underwoodiinhabits the Atlantic slopes and lowlands from southern Veracruz and extreme northern Oaxaca eastward across the base of the Yucatan Peninsula (possibly the species is extant in the northern part of the peninsula) to British Honduras and thence southeastward through the Caribbean lowlands and interior valleys in Honduras to central Nicaragua, where it apparently avoids the forested Caribbean lowlands and the dry Pacific lowlands of northwestern Nicaragua, but in the vicinity of Managua invades the Pacific lowlands and continues southward into northwestern Costa Rica as far as the Puntarenas Peninsula (Fig. 1). In México and Guatemala the species has not been taken at elevations of more than 350 meters, whereas farther south it occurs at higher elevations—780 meters at Silencio, Costa Rica, 830 meters on Montaña de Guaimaca, Honduras, 960 meters at Finca Tepeyac, Nicaragua, and 1200 meters at Finca Venecia, Nicaragua.Specimens examined.—1270, as follows:Mexico:Campeche: Balchacaj, FMNH 100406, UIMNH 20944-6; Encarnación, FMNH 27069-70, 75784, MCZ 28360, 29637, UIMNH 20948-58, 20965, USNM 134264-5; Escárcega, UMMZ 122999; *7.5 km. W Escárcega, KU 71229-43; Laguna Alvarado, 65 km. S Xpujil, KU 75084-9; Pacaitún, Río Candelaria, FMNH 83118-20; *Tres Brazos, FMNH 113101-22, UIMNH 20947; 10 km. W Xpujil, KU 75082-3.Chiapas: Palenque, UIMNH 47984, 49139-50, USNM 114973-8.Oaxaca: *5 km. N Chiltepec, KU 87015-23; 3 km. N Donají UMMZ 115249 (9); *3.7 km. N Donají, UMMZ 115250 (5); *43 km. N Matías Romero, UIMNH 42550-68; *3.5 km. N Palomares, TNHC 25185, 25321-31, 25341-68; 4.6 km.N Sarabia, UMMZ 115247 (2); *6.1 km. N Sarabia, UMMZ 115248 (11), *3 km. N Tolocita, KU 39655; Tuxtepec, KU 87024-40.Tabasco: 24 km. N Frontera, MCZ 35665-70; 0.8 km. E Río Tonolá, TNHC 25189; Teapa, UMMZ 119218 (4); *2.7 km. N Teapa, UMMZ 119216 (4); *10 km. N Teapa, UMMZ 119217 (6); *11.5 km. N Teapa, UMMZ 119219; *15.2 km. N Teapa, UMMZ 119220 (4); *17.6 km. N Teapa, UMMZ 119221 (12), 3.3 km. S Villahermosa, UMMZ 119215 (12), *17.6 km. S Villahermosa, UMMZ 119214 (12).Veracruz: 2.1 km. N Acayucan, UIMNH 42547-9; *6.4 km. NW Acayucan, UMMZ 115254 (14); 1.6 km. ESE Alvarado, UMMZ 115258 (39); *2.4 km. ESE Alvarado, UMMZ 115251 (2); *4.5 km. S Aquilera,UMMZ115252 (21); *8 km. SW Coatzacoalcos, UMMZ 119213 (10); 2.2 km. E Cosoleacaque, UMMZ 119222 (26); 10 km. SE Hueyapan, UMMZ 115255; 0.8 km. S Lerdo de Tejada, UMMZ 122778; *3.6 km. NE Minatítlán, TNHC 25150-2; 1.9 km. S Naranja, UMMZ 115253 (3); 4.5 km. NE Novillero, UMMZ 115256; San Andrés Tuxtla, FMNH 113124-8, UIMNH 20942-3.Yucatán: Chichén-Itzá, FMNH 36570, MCZ 2463 (2).British Honduras:Cayo: 6.2 km. S El Cayo, MCZ 37885-92.Stann Creek: Stann Creek, FMNH 49068.Guatemala:Alta Verapaz: 28.3 km. N Campur, KU 64578-90; Chinajá, KU 57425; Cubilquitz, UMMZ 90887, 90888 (4); Finca Chamá, UMMZ 90879 (13), 90880 (4), 90881, 90882 (28), 90883 (12), 90884 (46), 90885 (39), 90886 (20); *Finca Tinaja, BYU 16032; Panzós, UMMZ 90889 (2).Chiquimula: Chiquimula, UMMZ 98113; 2 km. N Esquipulas, UMMZ 106844.El petén: La Libertad, KU 57447-97, 59907-11 (skeletons), MCZ 21461, UMMZ 75332 (13), 75333 (11), 75334 (14), 75335 (10); Piedras Negras, FMNH 113123, UIMNH 20966; *5 km. S Piedras Negras, USNM 114951-72; Tikal, UMMZ 117981 (2); Toocog, 15 km. SE La Libertad, KU 57426-46.El Quiché: Finca Tesoro, UMMZ 89165 (5).Huehuetenango: Finca San Rafael, 16 km. SE Barillas, FMNH 40917-9.Izabal: Puerto Barrios, FMNH 20004-7; 8 km. S Puerto Barrios, KU 57507-37, 59991 (eggs), 59992 (tadpoles); Quirigua, CAS 69657-701; 2.5 km. NE Río Blanco, KU 57539; San Felípe, FMNH 35065.Zacapa: 14 km. ENE Mayuelas, KU 57502-6; 8 km. ENE Río Hondo, KU 57498-501.Honduras:Atlantidad: La Ceiba, UMMZ 91948 (2), USNM 117593-600; Lancetilla, MCZ 17981.Cortes: Lago Yojoa, AMNH 54917-9, 54957, 55134, KU 64563-77.El Paraiso: Valle de Jamastran, AMNH 54807-12.Francisco-Moranza: El Zamorano, AMNH 54873-81, KU 103223, UMMZ 123101; Montaña de Guaimaca, AMNH 54900-4 (8); Ranch San Diego, 19 km. SW Guaimaca, AMNH 53939.Itibucá: Vieja Itibucá, AMNH 54912-3.Nicaragua:Chontales: 3 km. SW Santo Tomás, KU 64770-9, 68308 (skeleton).Esteli: Finca Venecia, 7 km. N, 16 km. E Condega, KU 85296; 2.4 km. N Estelí, MCZ 28933-7. MANAGUA: 12-13 km. E Managua, KU 85297-301; *10 km. SW Tipitapa, UMMZ 119977 (10).Matagalpa: *Finca Tepeyac, 10.5 km. N, 9 km. E Matagalpa, KU 85302-3; Hacienda La Cumplida, KU 64780-96, 68309-11 (skeletons), UMMZ 116482 (8), 116483 (23), 116484 (3), 116485 (5), 119984 (3).Rivas: *Finca Amayo, 13 km. S, 14 km. E Rivas, KU 85304-7; 16 km. S Rivas, MCZ 29011-7; *20.5 km. SE Rivas, KU 85308-10; 5 km. SE San Pablo, KU 43111-4.Costa Rica:Guanacaste: Arenal, USC 6254 (2); *3 km. W Bagaces, USC 7019 (10); *3 km. NE Boca del Barranca, USC 8017 (21), *Finca San Bosco, USC 6272 (6), 6276 (3); *Guayabo de Bagaces, USC 7022 (4), 7023 (3), 7025; 12 km. S La Cruz, USC 8091 (2); *Laguna Arenal, USC 6262; *27 km. N Las Cañas, USC 8171 (6); *16 km. E Las Cañas, KU 102252-8; 16 km. SSE Las Cañas, KU 65090-5; *20 km. SE Las Cañas, KU 102251; Liberia, KU 30827-39; *7.3 km. N Liberia, USC 8096 (4); *10 km. N Liberia, USC 8085 (9); *7.5 km. SE Liberia, KU 65102-8, 68621-2 (skeletons); *14.7 km. S Liberia, USC 8238 (3); *4 km. W Liberia, KU 36847-57; 2 km. S Nicoya, USC 8230; *3-10 km. ESE Playa del Coco, USC 8012 (16), 8137 (14); *21.6 km. ESE Playa del Coco, USC 8138 (13); *Peñas Blancas, KU 102247-50; *Río Bebedero, 5 km. S Bebedero, KU 65089; *Río Higuerón, USC 7168 (2); Santa Cruz, USC 8232 (2); *Silencio, USC 6248; *Tenorio, KU 32313; Tilarán,KU 36858-60; *2 km. E Tilarán, KU 86403, *5 km. NE Tilarán, KU 36840-6 USC 6269.Puntarenas: Barranca, KU 32305-12, *5 km. WNW Barranca, UMMZ 119976 (2); *10 km. E Esparta, KU 86400-2; 1 km. WNW Esparta, KU 65101; *4 km. WNW Esparta, KU 65088; *10 km. WNW Esparta, KU 65063-87, 68616-20 (skeletons); *12 km. WNW Esparta, KU 65096-100, USC 8251; 21.8 km. W San Ramón, USC 8242 (15).Hyla robertmertensiTaylorHyla robertmertensiTaylor, Proc. Biol. Soc. Washington, 50:43, April 21, 1937 [Holotype.—CNHM 100096 (formerly EHT-HMS 2270) from Tapachula, Chiapas, México; H. M. Smith and E. H. Taylor collectors]. Smith and Taylor, Bull. U. S. Natl. Mus., 194:84, June 17, 1948; Univ. Kansas Sci. Bull., 33:326, March 20, 1950. Mertens. Senckenbergiana, 33:170, June 15, 1952; Senckenbergischen Naturf. Gesell., 487:30, December 1, 1952. Stuart, Contr. Lab. Vert. Biol., Univ. Michigan, 68:47, November, 1954. Duellman, Univ. Kansas Publ., Mus. Nat. Hist., 13:63, August 16, 1960. Duellman and Hoyt, Copeia, 1961 (2): 417, December 19, 1961. Porter, Herpetologica, 18:168, October 17, 1962. Stuart, Misc. Publ. Mus. Zool., Univ. Michigan, 122:36, April 2, 1963. Duellman and Trueb, Univ. Kansas Publ., Mus. Nat. Hist., 17:348, July 14, 1966.Diagnosis.—Brown lateral stripe wide, including loreal region and entire tympanum, extending to groin, bordered above by narrow white line; dorsum unicolor or with pair of dark lines (or rows of dashes) usually extending only to the sacral region; shanks having dark flecks, no transverse bars; interorbital bar lacking.Description and Variation.—Males attain a maximum snout-vent length of 26.4 mm. in Oaxaca, whereas in a sample from Acacoyagua, Chiapas, the largest male has a snout-vent length of 25.7 mm., and from La Trinidad, Guatemala, 24-6 mm. Specimens from the western part of the range (eastern Oaxaca) have slightly smaller heads and proportionately larger tympani than the more eastern populations (Table 1).The color pattern shows little variation, except in the nature of the dorsal markings. In a few specimens from throughout the range, but especially in the eastern part of the range, the dorsum lacks markings between the dorsolateral white lines. In most specimens the dorsal pattern consists of flecks or dashes arranged in two parallel longitudinal rows, and in some specimens the marks are fused into parallel lines. Small brown flecks are present on the dorsal surfaces of the shanks; in some specimens these flecks tend to form a longitudinal stripe on the shank. An interorbital dark mark is invariably absent.When active at nightHyla robertmertensiis pale yellow above with a white dorsolateral line and pale brown lateral stripe; the dorsal markings are faint. By day the dorsum is yellowish tan with brown markings. The dorsolateral stripe is creamy white, and the lateral stripe is dark brown (Pl. 14). The venter is white, and the iris is dull bronze. In breeding males the vocal sac is yellow.Remarks.—Although this species superficially resemblesHyla microcephala microcephala, the latter is easily distinguished by the narrow brown lateral stripe, as compared with the much wider stripe inH. robertmertensi. No other hylids in northern Central America and southern México can be confused with this species.Distribution.—Hyla robertmertensiinhabits the Pacific slopes (to elevations of 700 meters) and lowlands from eastern Oaxaca (east of the Plains of Tehuantepec)southeastward to central El Salvador. The species also occurs in the Cintalapa Valley (Atlantic drainage) in southwestern Chiapas (Fig. 2.) The distribution seems to be limited on the northwest and southeast by arid environments. The region in whichHyla robertmertensilives is characterized by higher rainfall and more luxuriant vegetation than occur on the Plains of Tehuantepec or on the Pacific lowlands of eastern El Salvador and southern Honduras. In addition to the localities listed below, Mertens (1952:30) recorded the species from Hacienda Cuyan-Cuya, Depto. Sonsonate, El Salvador.
[A]Longitudinal stripes present in two specimens.
[A]Longitudinal stripes present in two specimens.
When this frog is active at night its dorsum is pale yellow; faint flecks are present in some individuals. The white dorsolateral line usually is evident in the tympanic region, but in many individuals a dorsal pattern of lines and other marks is not evident. By day the dorsum changes to yellowish tan or pale brown with dark brown or reddish brown markings (Pl. 13). The venter is white, and the vocal sac in breeding males is yellow. The iris is pale bronze with a brown tint anterior and posterior to the pupil.
Remarks.—Hyla microcephala underwoodihas had a confused nomenclatural history. The taxon was first namedHyla microcephalaby Boulenger (1898); this name was preoccupied byHyla microcephalaCope (1886). Cole and Barbour (1906) and Kellogg (1932) used the nameHyla phlebodesStejneger (1906) for specimens of this frog from México. Dunn (1931, 1933, 1934) applied the nameHyla underwoodito Panamanian specimens that we identify asHyla phlebodes. Smith (1951) namedHyla microcephala martinifrom southern México and Guatemala and considered the northern populations to represent a subspecies distinct from the Costa RicanHyla microcephala underwoodi, despite the fact the Stuart (1935:39) stated that comparisons of specimens from El Petén, Guatemala, with the holotype ofHyla underwoodishowed only trivial differences.Much of the confusion regarding the nameHyla underwoodistems from the illustration given by Boulenger (1898:pl. 39, fig. 3) and reproduced by Taylor (1952:892), which shows a frog having a unicolor dorsum, dorsolateral white lines, and dark flanks. This pattern is in marked contrast to the pattern seen in most preserved specimens, which have the dorsum variously marked by dark brown lines or irregular marks. Smith (1951:185), in his description ofHyla microcephala martinifrom southern México, consideredH. underwoodito be a subspecies ofH. microcephalathat lacked dorsal dark markings.Data accumulated in 1961 through field studies by the senior author at the type locality, Bebedero, and other localities in Guanacaste and Puntarenas provinces in Costa Rica provide a reasonable explanation of the differences in color pattern. As noted in the preceding description of this subspecies, at night the dorsal markingsare not evident in many living individuals, whereas by day the dorsal markings are prominent. Most collectors prepare their specimens by day; consequently the majority of specimens have a pronounced dorsal pattern. Of the frogs collected in Costa Rica in 1961, some specimens were preserved at night; others from the same series were preserved by day. The differences are striking. In those preserved at night, dorsal markings are faint, if present at all. Some specimens closely match the figure given by Boulenger (1898).It is extremely doubtful if the frog described and illustrated by Boulenger could be associated with eitherHyla phlebodesorH. microcephala microcephala. Individuals of the former species lack a dorsolateral white line and always have some dorsal markings evident at night; furthermore,H. phlebodesis not known to occur on the Pacific lowlands.Hyla microcephala microcephalaoccurs farther southeast. Since there is no reason to doubt the type locality ofH. underwoodi, since specimens from the area around the type locality that have been preserved at night are like the holotype in pattern, and since the characteristics of the populations of the frogs in Guanacaste are the same as, or gradually blend into those of, populations in northern Central America and southern México, the frogs from throughout the entire range can be referred to one taxon, the earliest name for which isHyla underwoodiBoulenger, which herein is considered to be a subspecies ofH. microcephalaCope.
Remarks.—Hyla microcephala underwoodihas had a confused nomenclatural history. The taxon was first namedHyla microcephalaby Boulenger (1898); this name was preoccupied byHyla microcephalaCope (1886). Cole and Barbour (1906) and Kellogg (1932) used the nameHyla phlebodesStejneger (1906) for specimens of this frog from México. Dunn (1931, 1933, 1934) applied the nameHyla underwoodito Panamanian specimens that we identify asHyla phlebodes. Smith (1951) namedHyla microcephala martinifrom southern México and Guatemala and considered the northern populations to represent a subspecies distinct from the Costa RicanHyla microcephala underwoodi, despite the fact the Stuart (1935:39) stated that comparisons of specimens from El Petén, Guatemala, with the holotype ofHyla underwoodishowed only trivial differences.
Much of the confusion regarding the nameHyla underwoodistems from the illustration given by Boulenger (1898:pl. 39, fig. 3) and reproduced by Taylor (1952:892), which shows a frog having a unicolor dorsum, dorsolateral white lines, and dark flanks. This pattern is in marked contrast to the pattern seen in most preserved specimens, which have the dorsum variously marked by dark brown lines or irregular marks. Smith (1951:185), in his description ofHyla microcephala martinifrom southern México, consideredH. underwoodito be a subspecies ofH. microcephalathat lacked dorsal dark markings.
Data accumulated in 1961 through field studies by the senior author at the type locality, Bebedero, and other localities in Guanacaste and Puntarenas provinces in Costa Rica provide a reasonable explanation of the differences in color pattern. As noted in the preceding description of this subspecies, at night the dorsal markingsare not evident in many living individuals, whereas by day the dorsal markings are prominent. Most collectors prepare their specimens by day; consequently the majority of specimens have a pronounced dorsal pattern. Of the frogs collected in Costa Rica in 1961, some specimens were preserved at night; others from the same series were preserved by day. The differences are striking. In those preserved at night, dorsal markings are faint, if present at all. Some specimens closely match the figure given by Boulenger (1898).
It is extremely doubtful if the frog described and illustrated by Boulenger could be associated with eitherHyla phlebodesorH. microcephala microcephala. Individuals of the former species lack a dorsolateral white line and always have some dorsal markings evident at night; furthermore,H. phlebodesis not known to occur on the Pacific lowlands.Hyla microcephala microcephalaoccurs farther southeast. Since there is no reason to doubt the type locality ofH. underwoodi, since specimens from the area around the type locality that have been preserved at night are like the holotype in pattern, and since the characteristics of the populations of the frogs in Guanacaste are the same as, or gradually blend into those of, populations in northern Central America and southern México, the frogs from throughout the entire range can be referred to one taxon, the earliest name for which isHyla underwoodiBoulenger, which herein is considered to be a subspecies ofH. microcephalaCope.
Distribution.—Hyla microcephala underwoodiinhabits the Atlantic slopes and lowlands from southern Veracruz and extreme northern Oaxaca eastward across the base of the Yucatan Peninsula (possibly the species is extant in the northern part of the peninsula) to British Honduras and thence southeastward through the Caribbean lowlands and interior valleys in Honduras to central Nicaragua, where it apparently avoids the forested Caribbean lowlands and the dry Pacific lowlands of northwestern Nicaragua, but in the vicinity of Managua invades the Pacific lowlands and continues southward into northwestern Costa Rica as far as the Puntarenas Peninsula (Fig. 1). In México and Guatemala the species has not been taken at elevations of more than 350 meters, whereas farther south it occurs at higher elevations—780 meters at Silencio, Costa Rica, 830 meters on Montaña de Guaimaca, Honduras, 960 meters at Finca Tepeyac, Nicaragua, and 1200 meters at Finca Venecia, Nicaragua.
Specimens examined.—1270, as follows:Mexico:Campeche: Balchacaj, FMNH 100406, UIMNH 20944-6; Encarnación, FMNH 27069-70, 75784, MCZ 28360, 29637, UIMNH 20948-58, 20965, USNM 134264-5; Escárcega, UMMZ 122999; *7.5 km. W Escárcega, KU 71229-43; Laguna Alvarado, 65 km. S Xpujil, KU 75084-9; Pacaitún, Río Candelaria, FMNH 83118-20; *Tres Brazos, FMNH 113101-22, UIMNH 20947; 10 km. W Xpujil, KU 75082-3.Chiapas: Palenque, UIMNH 47984, 49139-50, USNM 114973-8.Oaxaca: *5 km. N Chiltepec, KU 87015-23; 3 km. N Donají UMMZ 115249 (9); *3.7 km. N Donají, UMMZ 115250 (5); *43 km. N Matías Romero, UIMNH 42550-68; *3.5 km. N Palomares, TNHC 25185, 25321-31, 25341-68; 4.6 km.N Sarabia, UMMZ 115247 (2); *6.1 km. N Sarabia, UMMZ 115248 (11), *3 km. N Tolocita, KU 39655; Tuxtepec, KU 87024-40.Tabasco: 24 km. N Frontera, MCZ 35665-70; 0.8 km. E Río Tonolá, TNHC 25189; Teapa, UMMZ 119218 (4); *2.7 km. N Teapa, UMMZ 119216 (4); *10 km. N Teapa, UMMZ 119217 (6); *11.5 km. N Teapa, UMMZ 119219; *15.2 km. N Teapa, UMMZ 119220 (4); *17.6 km. N Teapa, UMMZ 119221 (12), 3.3 km. S Villahermosa, UMMZ 119215 (12), *17.6 km. S Villahermosa, UMMZ 119214 (12).Veracruz: 2.1 km. N Acayucan, UIMNH 42547-9; *6.4 km. NW Acayucan, UMMZ 115254 (14); 1.6 km. ESE Alvarado, UMMZ 115258 (39); *2.4 km. ESE Alvarado, UMMZ 115251 (2); *4.5 km. S Aquilera,UMMZ115252 (21); *8 km. SW Coatzacoalcos, UMMZ 119213 (10); 2.2 km. E Cosoleacaque, UMMZ 119222 (26); 10 km. SE Hueyapan, UMMZ 115255; 0.8 km. S Lerdo de Tejada, UMMZ 122778; *3.6 km. NE Minatítlán, TNHC 25150-2; 1.9 km. S Naranja, UMMZ 115253 (3); 4.5 km. NE Novillero, UMMZ 115256; San Andrés Tuxtla, FMNH 113124-8, UIMNH 20942-3.Yucatán: Chichén-Itzá, FMNH 36570, MCZ 2463 (2).
British Honduras:Cayo: 6.2 km. S El Cayo, MCZ 37885-92.Stann Creek: Stann Creek, FMNH 49068.
Guatemala:Alta Verapaz: 28.3 km. N Campur, KU 64578-90; Chinajá, KU 57425; Cubilquitz, UMMZ 90887, 90888 (4); Finca Chamá, UMMZ 90879 (13), 90880 (4), 90881, 90882 (28), 90883 (12), 90884 (46), 90885 (39), 90886 (20); *Finca Tinaja, BYU 16032; Panzós, UMMZ 90889 (2).Chiquimula: Chiquimula, UMMZ 98113; 2 km. N Esquipulas, UMMZ 106844.El petén: La Libertad, KU 57447-97, 59907-11 (skeletons), MCZ 21461, UMMZ 75332 (13), 75333 (11), 75334 (14), 75335 (10); Piedras Negras, FMNH 113123, UIMNH 20966; *5 km. S Piedras Negras, USNM 114951-72; Tikal, UMMZ 117981 (2); Toocog, 15 km. SE La Libertad, KU 57426-46.El Quiché: Finca Tesoro, UMMZ 89165 (5).Huehuetenango: Finca San Rafael, 16 km. SE Barillas, FMNH 40917-9.Izabal: Puerto Barrios, FMNH 20004-7; 8 km. S Puerto Barrios, KU 57507-37, 59991 (eggs), 59992 (tadpoles); Quirigua, CAS 69657-701; 2.5 km. NE Río Blanco, KU 57539; San Felípe, FMNH 35065.Zacapa: 14 km. ENE Mayuelas, KU 57502-6; 8 km. ENE Río Hondo, KU 57498-501.
Honduras:Atlantidad: La Ceiba, UMMZ 91948 (2), USNM 117593-600; Lancetilla, MCZ 17981.Cortes: Lago Yojoa, AMNH 54917-9, 54957, 55134, KU 64563-77.El Paraiso: Valle de Jamastran, AMNH 54807-12.Francisco-Moranza: El Zamorano, AMNH 54873-81, KU 103223, UMMZ 123101; Montaña de Guaimaca, AMNH 54900-4 (8); Ranch San Diego, 19 km. SW Guaimaca, AMNH 53939.Itibucá: Vieja Itibucá, AMNH 54912-3.
Nicaragua:Chontales: 3 km. SW Santo Tomás, KU 64770-9, 68308 (skeleton).Esteli: Finca Venecia, 7 km. N, 16 km. E Condega, KU 85296; 2.4 km. N Estelí, MCZ 28933-7. MANAGUA: 12-13 km. E Managua, KU 85297-301; *10 km. SW Tipitapa, UMMZ 119977 (10).Matagalpa: *Finca Tepeyac, 10.5 km. N, 9 km. E Matagalpa, KU 85302-3; Hacienda La Cumplida, KU 64780-96, 68309-11 (skeletons), UMMZ 116482 (8), 116483 (23), 116484 (3), 116485 (5), 119984 (3).Rivas: *Finca Amayo, 13 km. S, 14 km. E Rivas, KU 85304-7; 16 km. S Rivas, MCZ 29011-7; *20.5 km. SE Rivas, KU 85308-10; 5 km. SE San Pablo, KU 43111-4.
Costa Rica:Guanacaste: Arenal, USC 6254 (2); *3 km. W Bagaces, USC 7019 (10); *3 km. NE Boca del Barranca, USC 8017 (21), *Finca San Bosco, USC 6272 (6), 6276 (3); *Guayabo de Bagaces, USC 7022 (4), 7023 (3), 7025; 12 km. S La Cruz, USC 8091 (2); *Laguna Arenal, USC 6262; *27 km. N Las Cañas, USC 8171 (6); *16 km. E Las Cañas, KU 102252-8; 16 km. SSE Las Cañas, KU 65090-5; *20 km. SE Las Cañas, KU 102251; Liberia, KU 30827-39; *7.3 km. N Liberia, USC 8096 (4); *10 km. N Liberia, USC 8085 (9); *7.5 km. SE Liberia, KU 65102-8, 68621-2 (skeletons); *14.7 km. S Liberia, USC 8238 (3); *4 km. W Liberia, KU 36847-57; 2 km. S Nicoya, USC 8230; *3-10 km. ESE Playa del Coco, USC 8012 (16), 8137 (14); *21.6 km. ESE Playa del Coco, USC 8138 (13); *Peñas Blancas, KU 102247-50; *Río Bebedero, 5 km. S Bebedero, KU 65089; *Río Higuerón, USC 7168 (2); Santa Cruz, USC 8232 (2); *Silencio, USC 6248; *Tenorio, KU 32313; Tilarán,KU 36858-60; *2 km. E Tilarán, KU 86403, *5 km. NE Tilarán, KU 36840-6 USC 6269.Puntarenas: Barranca, KU 32305-12, *5 km. WNW Barranca, UMMZ 119976 (2); *10 km. E Esparta, KU 86400-2; 1 km. WNW Esparta, KU 65101; *4 km. WNW Esparta, KU 65088; *10 km. WNW Esparta, KU 65063-87, 68616-20 (skeletons); *12 km. WNW Esparta, KU 65096-100, USC 8251; 21.8 km. W San Ramón, USC 8242 (15).
Hyla robertmertensiTaylor
Hyla robertmertensiTaylor, Proc. Biol. Soc. Washington, 50:43, April 21, 1937 [Holotype.—CNHM 100096 (formerly EHT-HMS 2270) from Tapachula, Chiapas, México; H. M. Smith and E. H. Taylor collectors]. Smith and Taylor, Bull. U. S. Natl. Mus., 194:84, June 17, 1948; Univ. Kansas Sci. Bull., 33:326, March 20, 1950. Mertens. Senckenbergiana, 33:170, June 15, 1952; Senckenbergischen Naturf. Gesell., 487:30, December 1, 1952. Stuart, Contr. Lab. Vert. Biol., Univ. Michigan, 68:47, November, 1954. Duellman, Univ. Kansas Publ., Mus. Nat. Hist., 13:63, August 16, 1960. Duellman and Hoyt, Copeia, 1961 (2): 417, December 19, 1961. Porter, Herpetologica, 18:168, October 17, 1962. Stuart, Misc. Publ. Mus. Zool., Univ. Michigan, 122:36, April 2, 1963. Duellman and Trueb, Univ. Kansas Publ., Mus. Nat. Hist., 17:348, July 14, 1966.
Hyla robertmertensiTaylor, Proc. Biol. Soc. Washington, 50:43, April 21, 1937 [Holotype.—CNHM 100096 (formerly EHT-HMS 2270) from Tapachula, Chiapas, México; H. M. Smith and E. H. Taylor collectors]. Smith and Taylor, Bull. U. S. Natl. Mus., 194:84, June 17, 1948; Univ. Kansas Sci. Bull., 33:326, March 20, 1950. Mertens. Senckenbergiana, 33:170, June 15, 1952; Senckenbergischen Naturf. Gesell., 487:30, December 1, 1952. Stuart, Contr. Lab. Vert. Biol., Univ. Michigan, 68:47, November, 1954. Duellman, Univ. Kansas Publ., Mus. Nat. Hist., 13:63, August 16, 1960. Duellman and Hoyt, Copeia, 1961 (2): 417, December 19, 1961. Porter, Herpetologica, 18:168, October 17, 1962. Stuart, Misc. Publ. Mus. Zool., Univ. Michigan, 122:36, April 2, 1963. Duellman and Trueb, Univ. Kansas Publ., Mus. Nat. Hist., 17:348, July 14, 1966.
Diagnosis.—Brown lateral stripe wide, including loreal region and entire tympanum, extending to groin, bordered above by narrow white line; dorsum unicolor or with pair of dark lines (or rows of dashes) usually extending only to the sacral region; shanks having dark flecks, no transverse bars; interorbital bar lacking.
Description and Variation.—Males attain a maximum snout-vent length of 26.4 mm. in Oaxaca, whereas in a sample from Acacoyagua, Chiapas, the largest male has a snout-vent length of 25.7 mm., and from La Trinidad, Guatemala, 24-6 mm. Specimens from the western part of the range (eastern Oaxaca) have slightly smaller heads and proportionately larger tympani than the more eastern populations (Table 1).
The color pattern shows little variation, except in the nature of the dorsal markings. In a few specimens from throughout the range, but especially in the eastern part of the range, the dorsum lacks markings between the dorsolateral white lines. In most specimens the dorsal pattern consists of flecks or dashes arranged in two parallel longitudinal rows, and in some specimens the marks are fused into parallel lines. Small brown flecks are present on the dorsal surfaces of the shanks; in some specimens these flecks tend to form a longitudinal stripe on the shank. An interorbital dark mark is invariably absent.
When active at nightHyla robertmertensiis pale yellow above with a white dorsolateral line and pale brown lateral stripe; the dorsal markings are faint. By day the dorsum is yellowish tan with brown markings. The dorsolateral stripe is creamy white, and the lateral stripe is dark brown (Pl. 14). The venter is white, and the iris is dull bronze. In breeding males the vocal sac is yellow.
Remarks.—Although this species superficially resemblesHyla microcephala microcephala, the latter is easily distinguished by the narrow brown lateral stripe, as compared with the much wider stripe inH. robertmertensi. No other hylids in northern Central America and southern México can be confused with this species.
Remarks.—Although this species superficially resemblesHyla microcephala microcephala, the latter is easily distinguished by the narrow brown lateral stripe, as compared with the much wider stripe inH. robertmertensi. No other hylids in northern Central America and southern México can be confused with this species.
Distribution.—Hyla robertmertensiinhabits the Pacific slopes (to elevations of 700 meters) and lowlands from eastern Oaxaca (east of the Plains of Tehuantepec)southeastward to central El Salvador. The species also occurs in the Cintalapa Valley (Atlantic drainage) in southwestern Chiapas (Fig. 2.) The distribution seems to be limited on the northwest and southeast by arid environments. The region in whichHyla robertmertensilives is characterized by higher rainfall and more luxuriant vegetation than occur on the Plains of Tehuantepec or on the Pacific lowlands of eastern El Salvador and southern Honduras. In addition to the localities listed below, Mertens (1952:30) recorded the species from Hacienda Cuyan-Cuya, Depto. Sonsonate, El Salvador.
Map Locality - Hyla robertmertensiFig. 2.Map showing locality records forHyla robertmertensi.
Specimens examined.—490, as follows:Mexico:Chiapas: Acacoyagua, USNM 114754-61; *2 km. W Acacoyagua, UMMZ 87843 (28), 87844 (50), 87845 (50), 87846 (45), 87847 (27), 87848 (3); 32 km. N Arriaga, KU 57619-24, 59917-8 (skeletons); Asunción, FMNH 100413, 100501-4, UIMNH 26989-90, USNM 134267; *La Esperanza, USNM 114737-48, 114750-3, 17 km. S Las Cruces, KU 57625-49, 59997 (eggs); 8.5 km. N Puerto Madero, UMMZ 119981 (2); *11.7 km. N Puerto Madero, UMMZ 119982; Tapachula, FMNH 100096, UIMNH 26987; *11 km. S Tapachula, KU 57605-18, 59916 (skeleton); Tonolá, FMNH 27073, 100505-10, UIMNH 26988.Oaxaca: Tapanatepec, UMMZ 115245 (2), *1.6 km. E Tapanatepec, UMMZ 115244 (14); *4.3 km. E Tapanatepec, UIMNH 38368-9; *7.5 km. W Tapanatepec, UMMZ 115246 (39); 12.8 km. W Tapanatepec, KU 65007-14; 7.2 km. WNW Zanatepec, UMMZ 115243 (77); *13.6 km. WNW Zanatepec, TNHC 25213-22; 22.7 km. WNW Zanatepec, TNHC 25203-9.
Guatemala:Jutiapa: Jutiapa, UMMZ 106848; La Trinidad, UMMZ 107733 (23).Retalhueleu: Casa Blanca, UMMZ 107732.
El Salvador:La Libertad: 16 km. NW Santa Tecla, KU 44112.San Salvador: 21.9 km. N San Salvador, UMMZ 119983 (6).
Hyla phlebodesStejneger
Hyla phlebodesStejneger, Proc. U. S. Natl. Mus., 30:817, June 4, 1906 [Holotype.—USNM 2997 from "San Carlos," Costa Rica; Burgdorf and Schild collectors]. Taylor, Proc. Biol. Soc. Washington, 50:44, April 21, 1937; Univ. Kansas Sci. Bull., 35:888, July 1, 1952; Univ. Kansas Sci. Bull., 39:25, November 18, 1958. Fouquette, Evolution, 14:484, December 16, 1960. Duellman and Trueb, Univ. Kansas Publ., Mus. Nat. Hist., 17:348, July 14, 1966.Hyla underwoodi, Dunn, Occas. Papers Boston Soc. Nat. Hist., 5:413, October 10, 1931; Occas. Papers Boston Soc. Nat. Hist. 8:72, June 7, 1933; Amer. Mus. Novitiates, 747.2, September 17, 1934, Gaige, Hartweg, and Stuart, Occas. Papers Mus. Zool., Univ. Michigan, 357:5, October 26, 1937. Breder, 1946, Bull. Amer. Mus. Nat. Hist., 86:416, August 22, 1946.
Hyla phlebodesStejneger, Proc. U. S. Natl. Mus., 30:817, June 4, 1906 [Holotype.—USNM 2997 from "San Carlos," Costa Rica; Burgdorf and Schild collectors]. Taylor, Proc. Biol. Soc. Washington, 50:44, April 21, 1937; Univ. Kansas Sci. Bull., 35:888, July 1, 1952; Univ. Kansas Sci. Bull., 39:25, November 18, 1958. Fouquette, Evolution, 14:484, December 16, 1960. Duellman and Trueb, Univ. Kansas Publ., Mus. Nat. Hist., 17:348, July 14, 1966.
Hyla underwoodi, Dunn, Occas. Papers Boston Soc. Nat. Hist., 5:413, October 10, 1931; Occas. Papers Boston Soc. Nat. Hist. 8:72, June 7, 1933; Amer. Mus. Novitiates, 747.2, September 17, 1934, Gaige, Hartweg, and Stuart, Occas. Papers Mus. Zool., Univ. Michigan, 357:5, October 26, 1937. Breder, 1946, Bull. Amer. Mus. Nat. Hist., 86:416, August 22, 1946.
Diagnosis.—Dark brown lateral stripe, if present, usually extending only to insertion of forearm, never posteriorly to sacral region; white line above brown stripe absent or faint; dorsal pattern weak, usually consisting of irregular dashes or interconnected lines; interorbital dark mark present; shanks having weakly defined transverse bars.
Description and variation.—In the majority of specimens (70%) the lateral dark stripe extends from the nostril to the eye and thence above the tympanum to a point above the insertion of the arm; in 17 per cent the stripe extends to the mid-flank, whereas in 13 per cent the stripe is absent. A narrow and faint white line is present on the canthus in some specimens, but no distinct white stripe is present above the lateral dark line posterior to the eye. An interorbital bar and transverse marks on the shanks are invariably present. The dorsal markings are variable, but in most specimens (92%) consist of either an X- or )(-shaped mark in the scapular region; in the other specimens the markings are irregular short lines or absent. Approximately equal numbers of specimens have a transverse bar, chevron, or broken lines in the sacral region, whereas about eight per cent of the specimens lack markings in the sacral region.
When active at night, individuals are pale yellowish tan with faint brown dorsal markings. By day they are tan with more distinct brown markings (Pl. 14). The thighs are pale yellow; the belly is white. The iris is pale creamy tan with brown flecks. In breeding males the vocal sac is yellow.
Tadpoles.—Tadpoles of this species have been found in an extensive grassy pond at Puerto Viejo, Costa Rica. The following description is based on KU 104099, a specimen in development stage 36 (Gosner, 1960).
Total length, 21.0 mm.; body length, 6.7 mm.; body slightly wider than deep, snout pointed; nostrils large, directed anteriorly, situated near end of snout; eyes small, situated dorsolaterally, directed laterally; spiracle sinistral, located just posteroventral to eye; anal tube dextral. Tail xiphicercal; caudal musculature moderately deep, extending far beyond posterior edge of fins; fins deepest at about midlength; dorsal fin extending onto body, slightly deeper than caudal musculature; ventral fin slightly shallower than musculature. Mouth small, terminal, lacking teeth and fringing papillae, but having finely serrate beaks. In preservative top of head olive-tan with brown flecks; dark stripe from snout through eye to posterior edge of body; belly white, flecked with brown anteriorly; tail creamy tan with grayish brown blotches. In life, dorsum of body reddish tan mottled with darker brown; lateral stripe dark brown; belly white, mottled with brown and black; caudal musculature heavily pigmentedwith grayish tan; posterior tip of tail marked with dark gray; caudal fins heavily blotched with grayish tan; iris orange-tan peripherally, red centrally (Pl. 15).
Remarks.—This species has been confused withHyla microcephala underwoodiby many workers. Dunn (1931, 1933, 1934) and Breder (1946) referred Panamanian specimens ofH. phlebodestoH. underwoodi; likewise, Gaige, Hartweg, and Stuart (1937) made the same error. Cole and Barbour (1906) and Kellog (1932) used the nameH. phlebodesfor Mexican specimens ofH. microcephala underwoodi. The similarity in color pattern ofH. microcephala underwoodiandH. phlebodeseasily accounts for the misapplication of names. Although both species have nearly identical dorsal color patterns, that ofH. microcephala underwoodiusually is bolder. Furthermore, in that species a narrow white line usually is present above the well-defined lateral dark stripe, whereas the lateral dark stripe is short and posterior to the eye is not bordered above by a white line inH. phlebodes.The type locality "San Carlos, Costa Rica" given by Stejneger (1906:817) apparently refers to a region, the Llanuras de San Carlos, in the northern part of Alajuela Province, Costa Rica.
Remarks.—This species has been confused withHyla microcephala underwoodiby many workers. Dunn (1931, 1933, 1934) and Breder (1946) referred Panamanian specimens ofH. phlebodestoH. underwoodi; likewise, Gaige, Hartweg, and Stuart (1937) made the same error. Cole and Barbour (1906) and Kellog (1932) used the nameH. phlebodesfor Mexican specimens ofH. microcephala underwoodi. The similarity in color pattern ofH. microcephala underwoodiandH. phlebodeseasily accounts for the misapplication of names. Although both species have nearly identical dorsal color patterns, that ofH. microcephala underwoodiusually is bolder. Furthermore, in that species a narrow white line usually is present above the well-defined lateral dark stripe, whereas the lateral dark stripe is short and posterior to the eye is not bordered above by a white line inH. phlebodes.
The type locality "San Carlos, Costa Rica" given by Stejneger (1906:817) apparently refers to a region, the Llanuras de San Carlos, in the northern part of Alajuela Province, Costa Rica.
Map Locality - Hyla phlebodesFig. 3.Map showing locality records forHyla phlebodes.
Distribution.—Hyla phlebodesinhabits humid tropical forests from southeastern Nicaragua southeastward on the Caribbean slopes and lowlands to the Canal Zone in Panamá, thence eastward in the Chucunaque Basin of eastern Panamá and onto the Pacific lowlands of Colombia (Fig. 3). The species alsoreaches the Pacific slopes in the Arenal Depression in northwestern Costa Rica and in the Panamanian isthmus, where it occurs in humid forests on the Pacific slope of El Valle and Cerro La Campana. Mostly the species is found at low elevations, but it occurs at 600 meters at Turrialba and at 700 meters at Finca San Bosco in Costa Rica.Specimens examined.—410, as follows:Nicaragua:Zelaya: Isla Grande del Maíz, MCZ 14848; Río Mico, El Recrero, UMMZ 79720 (6).Costa Rica:Alajuela: 12.4 km. N Florencia, MVZ 76108-10, USC 2628; *Las Playuelas, 11 km. S Los Chiles, USC 7216; Los Chiles, USC 7217, 7219; 3 km. NE Muelle de Arenal, USC 2644 (2); *"San Carlos," USNM 29970.Cartago: Chitaría, KU 103690; *1.6 km. E Río Reventazón Bridge, east of Turrialba, UMMZ 119978 (2); *Tunnel Camp, near Peralta, KU 32456, 32458-69, 41098 (skeleton); Turrialba, FMNH 101794, 103188-9, KU 25725-9, 32439-48, 41095-7 (skeletons), 64797-827, 68300-2 (skeletons), 68403 (eggs), 68404 (tadpoles), MCZ 29224-5, 29310-2, UMMZ 119979 (6), USC 31, 256 (2), 458 (2), 580, 594, 599 (7), 7074 (2), USNM 29933.Guanacaste: Arenal, USC 6254; *Finca San Bosco, USC 62724, 6276 (3), Guayabo de Bagaces, USC 7022 (3), 7023; *Laguna Arenal, USC 6262 (4); 3 km. NE Tilarán, USC 524; *5 km. NE Tilarán, USC 6269; *6 km. NE Tilarán, UMMZ 122653 (6), S-2680 (skeleton), USC 523 (8).Heredia: Puerto Viejo, KU 64828-63, 68303-7 (skeletons), 68405-6 (tadpoles), 104099-100 (tadpoles); *1.5 km. N Puerto Viejo, KU 64871; *1 km. S Puerto Viejo, KU 86432-40; *4.2 km. W Puerto Viejo, KU 64864-5; *5.9 km. W Puerto Viejo, KU 64866-70; *7.5 km. W Puerto Viejo, KU 86431.Limón: Batán, UMMZ 119980 (2); La Castilla, ANSP 23707; PuertoLimón, KU 32449-55.Panama:Bocas del Toro: 3.2 km. NW Almirante, KU 96026; Cayo de Agua, KU 96027-31; Fish Creek, KU 96032-4.Canal Zone: Barro Colorado Island, AMNH 69790, ANSP 23244-50; FMNH 13380, 22972-4; Juan Mina, AMNH 55429, UU 3899; *8.6-13.8 km. N Miraflores Locks, TNHC 23439, 23477, 23484-8, 23491, 23494-9, 23501-2, 23504-8, 23510-17, 23519-30, 23532-8, 23541-54, 23561. *Rio Chagres, AMNH 55431-4; Río Cocolí, 3.5 km. N Miraflores Locks, TNHC 23461, 23489-90, 23493, 23500, 23503, 23509, 23518, 23531, 23539-40; *Summit, ANSP 23361, KU 97788; *Three Rivers Plantation, SU 2130.Coclé: El Valle de Antón, AMNH 55435, 69786-9, ANSP 23506-9.Colón: Achiote, KU 77215-78; Ciricito, CAS 71499-500, 71505-6.Darién: Río Canclon at Río Chucunaque, UMMZ 126733; Río Chucunaque, near Yavisa, AMNH 51783.Panamá: Cero La Campana, FMNH 67847-50.Colombia:Chocó: Andagoya, FMNH 81856; Boca de Raspadura, AMNH 13570-8.
Distribution.—Hyla phlebodesinhabits humid tropical forests from southeastern Nicaragua southeastward on the Caribbean slopes and lowlands to the Canal Zone in Panamá, thence eastward in the Chucunaque Basin of eastern Panamá and onto the Pacific lowlands of Colombia (Fig. 3). The species alsoreaches the Pacific slopes in the Arenal Depression in northwestern Costa Rica and in the Panamanian isthmus, where it occurs in humid forests on the Pacific slope of El Valle and Cerro La Campana. Mostly the species is found at low elevations, but it occurs at 600 meters at Turrialba and at 700 meters at Finca San Bosco in Costa Rica.
Specimens examined.—410, as follows:Nicaragua:Zelaya: Isla Grande del Maíz, MCZ 14848; Río Mico, El Recrero, UMMZ 79720 (6).
Costa Rica:Alajuela: 12.4 km. N Florencia, MVZ 76108-10, USC 2628; *Las Playuelas, 11 km. S Los Chiles, USC 7216; Los Chiles, USC 7217, 7219; 3 km. NE Muelle de Arenal, USC 2644 (2); *"San Carlos," USNM 29970.Cartago: Chitaría, KU 103690; *1.6 km. E Río Reventazón Bridge, east of Turrialba, UMMZ 119978 (2); *Tunnel Camp, near Peralta, KU 32456, 32458-69, 41098 (skeleton); Turrialba, FMNH 101794, 103188-9, KU 25725-9, 32439-48, 41095-7 (skeletons), 64797-827, 68300-2 (skeletons), 68403 (eggs), 68404 (tadpoles), MCZ 29224-5, 29310-2, UMMZ 119979 (6), USC 31, 256 (2), 458 (2), 580, 594, 599 (7), 7074 (2), USNM 29933.Guanacaste: Arenal, USC 6254; *Finca San Bosco, USC 62724, 6276 (3), Guayabo de Bagaces, USC 7022 (3), 7023; *Laguna Arenal, USC 6262 (4); 3 km. NE Tilarán, USC 524; *5 km. NE Tilarán, USC 6269; *6 km. NE Tilarán, UMMZ 122653 (6), S-2680 (skeleton), USC 523 (8).Heredia: Puerto Viejo, KU 64828-63, 68303-7 (skeletons), 68405-6 (tadpoles), 104099-100 (tadpoles); *1.5 km. N Puerto Viejo, KU 64871; *1 km. S Puerto Viejo, KU 86432-40; *4.2 km. W Puerto Viejo, KU 64864-5; *5.9 km. W Puerto Viejo, KU 64866-70; *7.5 km. W Puerto Viejo, KU 86431.Limón: Batán, UMMZ 119980 (2); La Castilla, ANSP 23707; PuertoLimón, KU 32449-55.
Panama:Bocas del Toro: 3.2 km. NW Almirante, KU 96026; Cayo de Agua, KU 96027-31; Fish Creek, KU 96032-4.Canal Zone: Barro Colorado Island, AMNH 69790, ANSP 23244-50; FMNH 13380, 22972-4; Juan Mina, AMNH 55429, UU 3899; *8.6-13.8 km. N Miraflores Locks, TNHC 23439, 23477, 23484-8, 23491, 23494-9, 23501-2, 23504-8, 23510-17, 23519-30, 23532-8, 23541-54, 23561. *Rio Chagres, AMNH 55431-4; Río Cocolí, 3.5 km. N Miraflores Locks, TNHC 23461, 23489-90, 23493, 23500, 23503, 23509, 23518, 23531, 23539-40; *Summit, ANSP 23361, KU 97788; *Three Rivers Plantation, SU 2130.Coclé: El Valle de Antón, AMNH 55435, 69786-9, ANSP 23506-9.Colón: Achiote, KU 77215-78; Ciricito, CAS 71499-500, 71505-6.Darién: Río Canclon at Río Chucunaque, UMMZ 126733; Río Chucunaque, near Yavisa, AMNH 51783.Panamá: Cero La Campana, FMNH 67847-50.
Colombia:Chocó: Andagoya, FMNH 81856; Boca de Raspadura, AMNH 13570-8.
Hyla sartoriSmith
Hyla underwoodi(in part), Smith and Taylor, Bull. U. S. Natl. Mus., 194:85, June 17, 1948.Hyla microcephala sartoriSmith, Herpetologica, 7:186, December 31, 1951 [Holotype.—UIMNH 20934 from 1 mile north of Organos, south of El Treinte, Guerrero, México; H. M. Smith and E. H. Taylor collectors]. Duellman, Univ. Kansas Publ., Mus. Nat. Hist., 15:124, December 20, 1961. Porter, Herpetologica, 18:168, October 17, 1962. Davis and Dixon, Herpetologica, 20:230, January 25, 1965. Duellman, Univ. Kansas Publ. Mus. Nat. Hist., 15:652, December 30, 1965.
Hyla underwoodi(in part), Smith and Taylor, Bull. U. S. Natl. Mus., 194:85, June 17, 1948.
Hyla microcephala sartoriSmith, Herpetologica, 7:186, December 31, 1951 [Holotype.—UIMNH 20934 from 1 mile north of Organos, south of El Treinte, Guerrero, México; H. M. Smith and E. H. Taylor collectors]. Duellman, Univ. Kansas Publ., Mus. Nat. Hist., 15:124, December 20, 1961. Porter, Herpetologica, 18:168, October 17, 1962. Davis and Dixon, Herpetologica, 20:230, January 25, 1965. Duellman, Univ. Kansas Publ. Mus. Nat. Hist., 15:652, December 30, 1965.
Diagnosis.—Dorsum tan with broad dark brown chevrons or transverse bars; shanks marked with two or three broad transverse bars; dorsolateral stripes absent.
Description and variation.—No noticeable geographic variation is apparent in either structural features or coloration in this species. All specimens lack a dorsolateral dark stripe and white line, although a dark line is present on thecanthus and dissipates in the loreal region. A broad interorbital brown bar is present in all specimens. The color pattern on the dorsum invariably consists of a broad, dark, chevron-shaped mark in the scapular region and a broad dark chevron or transverse bar in the sacral region. The shanks invariably have two or three dark brown transverse bars.
When active at night individuals are yellowish tan above with chocolate brown markings (Pl. 14). The belly is white, and the thighs are pale yellowish tan. The iris is dark bronze-color. In breeding males the vocal sac is yellow. By day some individuals were observed to change to creamy gray with distinct darker markings.
Remarks.—Although tadpoles of this species have not been found, observations on the breeding sites indicate that the tadpoles probably develop in ponds. Except for calling males observed around a pool in a stream-bed 11.8 kilometers west-northwest of Tierra Colorada, Guerrero, all breeding congregations have been found at temporary ponds.Smith (1951:186) namedHyla sartorias a subspecies ofHyla microcephala. This subspecific relationship seemed reasonable until analysis of the mating calls showed that the call ofH. sartoriis more nearly like that ofH. phlebodesthan that ofH. microcephala. The broad hiatus separating the ranges ofH. microcephalaandH. sartoriis additional evidence for consideringH. sartorias a distinct species.
Remarks.—Although tadpoles of this species have not been found, observations on the breeding sites indicate that the tadpoles probably develop in ponds. Except for calling males observed around a pool in a stream-bed 11.8 kilometers west-northwest of Tierra Colorada, Guerrero, all breeding congregations have been found at temporary ponds.
Smith (1951:186) namedHyla sartorias a subspecies ofHyla microcephala. This subspecific relationship seemed reasonable until analysis of the mating calls showed that the call ofH. sartoriis more nearly like that ofH. phlebodesthan that ofH. microcephala. The broad hiatus separating the ranges ofH. microcephalaandH. sartoriis additional evidence for consideringH. sartorias a distinct species.
Map Locality - Hyla sartoriFig. 4.Map showing locality records forHyla sartori.
Distribution.—Hyla sartorioccurs in mesophytic forests to elevations of about 300 meters on the Pacific slopes of southern México from southwestern Jalisco to south-central Oaxaca (Fig. 4). The lack of specimens from Colima and Michoacán probably reflects inadequate collecting instead of the absence of the species there. On the basis of available habitat the species would be expected to occur in Nayarit, but extensive collecting there has failed to reveal its presence. The semi-arid Plains of Tehuantepec apparently limit the distribution to the east.
Specimens examined.—190, as follows:México:Guerrero: 5 km. E Acapulco, AMNH 54611-2; 23.2 km. N Acapulco, UIMNH 26404-7; Colonia Buenas Aires, 23 km. E Tecpán de Galeana, UMMZ 119223 (7); *El Limoncito, FMNH 75785, 100390-402, 104631, 104633, UMMZ 117250, USNM 134266; El Treinte, FMNH 100403, UIMNH 20935-7; Laguna Coyuca, AMNH 59686; La Venta, MCZ 29635; *Morjonares, UIMNH 26392-402; 1.6 km. N Organos, FMNH 100404-5, UIMNH 20933-4; 19.2 km. S Petaquillas, UIMNH 26408; 6.1 km. E. Tecpán de Galeana, TNHC 23396-408; *11.2 km. N Tierra Colorada, UIMNH 26403; 11.8 km. WNW Tierra Colorada, UMMZ 119225 (51), S-2677-9 (skeletons); Zacualpán, UMMZ 119224 (6).Jalisco: 6.4 km. NE La Resolana, KU 67853-69; 24 km NE La Resolana, KU 67870-3.Oaxaca: 3 km. N Pochutla, KU 57539; 13.4 km. N Pochutla, UMMZ 123495 (40).
CRANIAL OSTEOLOGY
The frogs of theHyla microcephalagroup have a minimal amount of cranial ossification as compared to more generalized hylid skulls, such asSmilisca(Duellman and Trueb, 1966). In theHyla microcephalagroup the sphenethmoid is small and short, and a large frontoparietal fontanelle is present. The quadratojugal exists only as a small spur and is not in contact with the maxillary. The proötics are poorly developed. The anterior and posterior arms of the squamosal are short; the anterior arm extends no more than one-fourth of the distance to the maxillary, and the posterior arm does not have a bony connection with the proötic. The nasal lacks a maxillary process, and the medial ramus of the pterygoid lacks a bony connection to the proötic.
Teeth are absent on the parasphenoid and palatines, but present on the maxillaries, premaxillaries, and prevomers. The teeth are simple, pointed, and slightly curved. Although the number of teeth varies (Table 3), no consistent differences between the species are apparent.
Table 3.
—Variation in the Number of Teeth in the Species of the Hyla Microcephala Group. (N=Number of Jaws, or Twice the Number of Individuals; Means are Given in Parentheses After the Observed Ranges).
SpeciesNMaxillaryPremaxillaryPrevomerH. microcephala3231-47(37.8)4-13(8.9)2-4(3.2)H. phlebodes1038-45(40.1)8-13(10.3)2-5(3.9)H. robertmertensi623-43(32.8)7-12(10.5)2-3(2.7)H. sartori627-43(38.2)9-10(9.3)3-4(3.7)
PLATE 13Adult FrogsUpper figure,Hyla microcephala microcephala(KU 64593);middle figure,H. microcephala underwoodi(KU 64565);lower figure,H. microcephala underwoodi(UMMZ 115247).All approximately ×3.
PLATE 14Adult FrogsUpper figure,Hyla robertmertensi(UMMZ 115243);middle figure,H. phlebodes(KU 64798);lower figure,H. sartori(UMMZ 119225).All approximately ×3.
PLATE 15TadpolrsTadpoles ofHyla microcephalagroup:upper figure,H. m. microcephala(KU 104097);lower figure,H. phlebodes(KU 104099).Both ×4.
PLATE 16AudiospectrogramsAudiospectrograms and sections of mating calls ofHyla microcephalagroup:(a)H. m. microcephala(KU Tape No. 19);(b)H. robertmertensi(KU Tape No. 41);(c)H. phlebodes(KU Tape No. 6);(d)H. sartori(KU Tape No. 190).
Table 4.
—Comparative Cranial Osteology of Hyla microcephala Group
Skulls Dorsal ViewFig. 5.Dorsal views of the skulls of (a)Hyla m. microcephala(KU 68293) and (b)H. sartori(UMMZ S-2677). Both × 12.
Skulls Dorsal ViewFig. 6.Dorsal views of skulls of (a)Hyla phlebodes(KU 68303) and (b)H. robertmertensi(KU 59917). Both × 12.
Despite the great reduction in the ossification of the cranial elements, certain apparently consistent differences exist betweenthe species seem to be consistent. The most notable differences are: 1) amount of ossification of the frontoparietals and consequent shape and size of the frontoparietal fontanelle, 2) shape of the nasals, 3) shape and extent of the sphenethmoid, and 4) shape of the columella (Table 4,Figs. 5-6). On the basis of these characters,Hyla microcephalacan be set apart from the other species and characterized as having a poorly ossified frontoparietal and correspondingly large frontoparietalfontanelle; long, slender, arcuate nasals; extremely short sphenethmoid; and expanded distal end of the columella. The other species in the group (phlebodes,robertmertensi, andsartori) have more ossification of the frontoparietals, broader nasals, only a moderately short sphenethmoid, and an unexpanded distal end of the columella. Among these three species, the skulls ofphlebodesandrobertmertensiare most nearly alike, whereas the skull ofsartoridiffers by having a differently shaped frontoparietal fontanelle, broader nasals, and an ossified anterior extension of the sphenethmoid between the nasals (compareFig. 5bwithFig. 6 a-b).
Although all skulls examined belong to breeding adults, the extent of the ossification of the frontoparietals and the resulting shape of the frontoparietal fontanelle might be correlated with the age of the frog. Nevertheless, in the 24 skulls ofHyla microcephalaexamined, the frontoparietals are less extensively ossified than in the skulls of the other species. The trivial differences among the other three species certainly are suggestive of close relationship, but on the basis of present knowledge of the evolutionary trends in hylid cranial osteology, the differences offer little evidence for determining phylogenetic lineage.