The Amphibians and Reptiles of Michoacan, Mexico - Part 7
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Part 7

These specimens const.i.tute the southernmost record for the species, which ranges in semi-arid habitats from southern Arizona southward along the Pacific lowlands of Mexico to Colima and inland on the Mexican Plateau in Jalisco.

~Phyllomedusa dacnicolor~ Cope

_Phyllomedusa dacnicolor_ Cope, Proc. Acad. Nat. Sci.

Philadelphia, 16:181, September 30, 1864.--Colima, Colima, Mexico. Funkhouser, Occ. Pap. Nat. Hist. Mus. Stanford Univ., 5:37, April 1, 1957.

_Agalychnis alcorni_ Taylor, Copeia, no. 2:31, June 2, 1952.--Rio Tepalcatepec, 17 miles south of Apatzingan, Michoacan, Mexico.

_Agalychnis dacnicolor_, Duellman, Herpetologica, 13:29, March 30, 1957.

_Phyllomedusa alcorni_, Funkhouser, Occ. Pap. Nat. Hist.

Mus. Stanford Univ., 5:30, April 1, 1957.

Aguililla (13); Apatzingan (7); Charapendo; Coahuayana (3); Coalcoman (54); El Sabino; Huetamo Road (2); La Orilla; La Placita; Nueva Italia (4); 32 km. E of Neuva Italia (2); Rio Cancita, 14 km. E of Apatzingan; Rio Tepalcatepec, 27 km. S of Apatzingan; Salitre de Estopilas (2); Tzitzio (4).

This large tree frog has been found only in the lowlands below elevation of about 1000 meters, usually in arid tropical scrub forest. Calling males were heard on rainy nights throughout the rainy season; in nearly every instance both males and females were found in low trees and bushes. On summer nights when there had been no rain, adults were found sitting on bushes in the scrub forest.

At Coalcoman on July 1, 1955, a chorus was heard at midday. About forty _Phyllomedusa dacnicolor_ were found in one guayava bush at the edge of a recently dried pond. Individual males were calling; clasping males were silent. The call is a barking groan. Fifteen individual egg ma.s.ses were hanging from branches and leaves in tear-drop fashion. Each egg ma.s.s contained 100 to 350 pale green eggs, located only in the exterior part of the clear gelatinous ma.s.s. Two composite egg ma.s.ses appeared to have been made up by egg deposition on the part of three to five females (Pl. 2, Fig. 2).

As shown by Duellman (1957a), the characters used by Taylor (1952) to diagnose _Phyllomedusa alcorni_ are s.e.xually dimorphic. Funkhouser (1957) apparently was unaware of this s.e.xual dimorphism, for she recognized _P. alcorni_ and _P. dacnicolor_ as distinct species.

~Phrynohyas inflata~ (Taylor)

_Acrodytes inflata_ Taylor, Univ. Kansas Sci. Bull., 30:64, June 12, 1944.--La Venta, Guerrero, Mexico.

_Phrynohyas inflata_, Duellman, Misc. Publ. Mus. Zool. Univ.

Michigan, 96:19, February 1, 1956.

_Phrynohyas corasterias_ Shannon and Humphrey, Herpetologica, 13:15, March 30, 1957.--4.8 miles east of San Blas, Nayarit, Mexico.

Barranca de Bejuco.

One specimen of this large species was collected in 1951; it was found on a low branch in tropical semi-deciduous forest at an elevation of 65 meters. In life there were olive-gray blotches on a pale gray dorsum; the iris was a dark golden color.

This species, which is known from only a few specimens, seems to be restricted to the coastal lowlands and low foothills from Guerrero northward to Nayarit. Shannon and Humphrey (1957) described _Phrynohyas corasterias_ from Nayarit. Their description was based on a small female having a snout-vent length of 34.4 mm. The new species was diagnosed as differing from _P. inflata_ in having less webbing on the feet, a poorly developed supratympanic fold, a more pustulate dorsum, and marked differences in dorsal pattern, color, and nature of antebrachial banding. The significance of the webbing was questioned by Shannon and Humphrey. The nature of the supratympanic fold and dorsal pustules changes with age (Duellman, 1956a:31). _Phrynohyas inflata_ is known to attain a snout-vent length of 95 mm. Dermal structures that undergo ontogenetic change are of little importance in comparing a juvenile with a large adult. The only significant difference in color pattern between _P. inflata_ and _P. corasterias_ is the presence of wide transverse bands on the limbs of the latter. In this respect _P. corasterias_ approaches _P. latifasciata_, a species known only from two specimens from southern Sinaloa. The acquisition of additional specimens from Jalisco, Nayarit, and Sinaloa may show that _P. inflata_ and _P.

latifasciata_ are conspecific, as suggested by Duellman (1956a:21).

Nonetheless, the specimen on which the description of _P. corasterias_ was based is not sufficiently different from the known specimens of _P.

inflata_ to warrant specific recognition.

~Hyla arenicolor~

_Hyla arenicolor_ Cope, Jour. Acad. Nat. Sci. Philadelphia, ser. 2, 6:84, July, 1866.--Northern Sonora, Mexico. Type locality restricted to Santa Rita Mountains, Pima County, Arizona, by Smith and Taylor (1950a:354).

Agua Cerca; Cascada Tzararacua (3); Chinapa; Cojumatlan; Dos Aguas; El Sabino (25); El Espinal; Lago de Camecuaro; Lombardia (2); Tupataro; Zinapecuaro.

Alt.i.tudinally this frog ranges from 500 to 2100 meters; although the environments in which it has been found vary from open arid tropical scrub forest to pine forest, it usually is found near rocky streams in these habitats. There is great disparity in size between specimens from the mountains and those from the Tepalcatepec Valley. Seven males from elevations in excess of 1400 meters have an average snout-vent length of 34.7 mm.; nine from elevations below 1000 meters have an average snout-vent length of 49.1 mm. In life a male collected at night at Lombardia (UMMZ 112846) had dark brown spots on a grayish brown dorsum; the groin, anterior and posterior surfaces of the thighs, and ventral surfaces of the hind limbs and palms were yellowish orange. The belly and tips of digits were white; the vocal sac was purplish brown, and the iris was dark grayish gold. In contrast, a specimen obtained in the daytime at Chinapa (UMMZ 119204) had indistinct gray spots on a pale ashy gray dorsum; the flash colors were yellow. After dark the spots were dark olive-brown on a grayish brown dorsum.

Two males were found calling from a rocky stream near Lombardia on July 12, 1955. The call is a nasal "ah-ah-ah-ah."

~Hyla baudini~ Dumeril and Bibron

_Hyla baudinii_ Dumeril and Bibron, Erpetologie generale, vol. 8:564, 1841.--Mexico. Type locality restricted to Cordoba, Veracruz, Mexico, by Smith and Taylor (1950a:346).

Aguililla (5); Apatzingan (30); Arteaga; Buena Vista; Charapendo; Coahuayana; Cofradia (4); El Sabino (12); La Placita; La Playa; Maruata; Nueva Italia (3); 32 km. E of Nueva Italia (2); Ostula (4); Rio Tepalcatepec, 25 km. S of Apatzingan (3); Salitre de Estopilas; San Jose de la Montana (2); Tumbiscatio; Tzitzio.

This tree frog is widespread in the coastal lowlands and in the Tepalcatepec Valley up to elevations of about 1200 meters. It is found in numbers in the early part of the rainy season, at which time males were heard calling from bushes and trees along ditches and temporary ponds. The call is a loud nasal "waank-waank-waank." One individual that was emitting a long and unusually high-pitched call was found to have one hind limb engulfed by a _Leptodeira maculata_.

When active at night these frogs usually are pale tan to reddish brown above with dark brown markings. A specimen found sitting on a maguey plant in the daytime was pale ashy gray with a pale green upper lip.

~Hyla bistincta~ Cope

_Hyla bistincta_ Cope, Proc. Amer. Philos. Soc., 17:87, 1877.--Veracruz, Mexico. Type locality restricted to Acultzingo, Veracruz, Mexico, by Smith and Taylor (1950a:346).

Cerro San Andres; Dos Aguas (2); Los Conejos (3); Uruapan (50).

In the Parque Nacional at Uruapan this species was found in abundance during the day. The frogs hide in an entanglement of vines and vegetation overhanging several small spring-fed streams. Tadpoles were in the rocky streams, and metamorphosing young were on vegetation at the edges of the streams.

In life the dorsum is greenish tan with brown mottling; in some individuals the entire dorsum is dark chocolate brown. The flanks are pale lemon yellow barred with lavender-brown. Notes on the color of a living frog from Dos Aguas (UMMZ 119193) are: Dorsal ground color a medium shade of brown with dark brown flecks; flanks black with silvery white and pale yellow spots; belly pale yellowish white; throat mottled with grayish brown; iris pale copper color.

[Ill.u.s.tration: FIG. 8. Tadpole of _Hyla bistincta_ (UMMZ 115231) from Uruapan, Michoacan. 2.]

Description of Tadpole: Body somewhat depressed; maximum width of body slightly more than one-half of body length. Nostrils placed dorsolaterally and directed anteriorly, situated about midway between tip of snout and eye. Eyes of moderate size, dorsolateral in position and directed upwards. Tail about twice as long as body, thrice as long as deep, and tapering gradually to a rounded tip. Tail-musculature not extending to tip of tail fin. Spiracle sinistral, lateral, and situated at midbody. Vent dextral; the cloacal tube extending along ventral part of tail for a distance equal to about one-eighth of body length (Fig.

8). Average body length of six tadpoles with small hind limb buds, 19.5 mm.; tail length, 38.3 mm. Mouth ventral, its width equal to about two-thirds of greatest width of body. Lips bordered by two rows of small papillae; row of larger papillae between upper lip and outer upper tooth-row, similar row between lower lip and outer lower tooth-row; laterally these rows degenerating into numerous small papillae. h.o.r.n.y beaks well developed; upper beak moderately arched and deeply indented; lower beak slightly indented. Serrations of beaks blunt and peglike, moderately developed on both beaks, but slightly stronger on lower one.

Tooth-rows 2/3; upper rows nearly equal in length and slightly longer than lower rows, which are subequal in length; inner upper tooth row interrupted medially by rounded notch; inner lower tooth-row turned downward laterally; teeth in all rows about equal in size, but decreasing in length laterally (Fig. 9).

[Ill.u.s.tration: FIG. 9. Mouthparts of larval _Hyla bistincta_ (UMMZ 115231) from Uruapan, Michoacan. 15.]

Color in formalin: pale grayish brown dorsally and laterally; pale gray ventrally; tail-musculature brown; tail-fin translucent with scattered melanoph.o.r.es most numerous on upper fin.

In most details these tadpoles resemble those of _Hyla robertsorum_ described by Rabb and Mosimann (1955).

Four metamorphosing young have snout-vent lengths of 23.0-23.5 (23.2); a completely metamorphosed individual has a snout-vent length of 24.8 mm.

In Michoacan this stream-breeding hylid occurs at elevations of 1,600 to 2,400 meters in the Sierra de Coalcoman and in the mountains rising from the Mexican Plateau.

~Hyla eximia~ Baird

_Hyla eximia_ Baird, Proc. Acad. Nat. Sci. Philadelphia, 7:61, October 20, 1854.--Valley of Mexico. Type locality restricted to Coyoacan, Distrito Federal, Mexico, by Smith and Taylor (1950a:329).

_Hyla microeximia_ Maslin, Herpetologica, 13:81, July 10, 1957.--3 miles northwest of Jocotepec, Jalisco, Mexico.

Ciudad Hidalgo (36); Cuitzeo; 29 km. NW of Jacona; Jiquilpan (2); Lago de Camecuaro (2); Lago de Patzcuaro (129); Los Reyes; Morelia; Sahuayo (3); San Gregorio (63); Tangamandapio (4); Temazcal (26); Tupataro; Tuxpan (15); Undameo (2); Uruapan (20); Zacapu; Zamora (27); Zinapecuaro (10).