The Amphibians and Reptiles of Michoacan, Mexico Part 6

~Tomodactylus fuscus~ Davis and Dixon

_Tomodactylus fuscus_ Davis and Dixon, Herpetologica, 11:157, July 15, 1955.--1.5 miles southeast of Huitzilac, Morelos, Mexico.

Los Cantiles (2); 28 km. E of Morelia.

The range of this species includes the Sierra Ajusco in Mexico and Morelos and thence westward to the Serrania Ucareo in Michoacan. The specimen from 28 kilometers east of Morelia was found in an oak forest on a steep hillside at an elevation of 2100 meters. One from Los Cantiles was calling from a steep cliff at an elevation of 2200 meters in pine-oak forest. This specimen (UMMZ 119156) in life had a pale olive-brown dorsum with irregular dark brown mottling and transverse bars on the limbs. The interorbital bar, the upper arms, and the tips of the dorsal pustules were pale orange; the iris was pale grayish gold (Pl. 3, Fig. 2).

~Tomodactylus nitidus nitidus~ (Peters)

_Liuperus nitidus_ Peters, Monats. Akad. Wiss. Berlin, p.

878, 1869.--Izucar de Matamoras, Puebla, Mexico.

_Tomodactylus amulae_ Gunther, Biologia Centrali-Americana, Reptilia and Batrachia, p. 219, April, 1900.--Amula, Guerrero, Mexico.

_Tomodactylus nitidus nitidus_, Dixon, Texas Jour. Sci., 9:385, December, 1957.

Copuyo (15); Tuxpan (8); Tzitzio (11).

One specimen from Tzitzio (UMMZ 99155) was referred to _Tomodactylus nitidus petersi_ by Dixon (1957:390). A re-examination of this specimen, and examination of ten others from the same locality (UMMZ 121571) reveals that the relatively small size of the tympanum and absence of dense ventral spotting place these specimens closer to _T. nitidus nitidus_ than to _T. nitidus petersi_.

The specimens from Tuxpan (UMMZ 114303-4) had in life a gray to olive tan ground color with dark olive-green markings, bright yellow thighs with olive-green transverse bands, yellowish tan shanks with olive-green bars, yellow groin, white inguinal glands with black markings, grayish white belly with scattered brownish black spots in some specimens, and a deep golden iris (Pl. 4, Fig. 1). These specimens were found calling from bushes in a rocky field at an elevation of 1800 meters. The call is a high-pitched "pee-ee-eep."

~Tomodactylus nitidus orarius~ Dixon

_Tomodactylus nitidus orarius_ Dixon, Texas Jour. Sci., 9:392, December, 1957.--4.5 miles southwest of Tecolapa, Colima, Mexico.

La Placita (3); Pomaro.

These specimens, referred to _Tomodactylus petersi_ by Duellman (1954b:5), were included in _T. nitidus orarius_ by Dixon (1957:392).

Color notes based on living individuals from Tecolapa, Colima (UMMZ 114312 and 116922), are: gray above mottled with brown; venter dirty white; anterior and posterior surfaces of thighs bright yellow; iris pale golden (Pl. 4, Fig. 2). The call is a soft "braa" usually followed by three high notes: "braaa-eep-ee-eep." In Michoacan this subspecies has been found only in the coastal region and the lower foothills of the Sierra de Coalcoman, an area in which it replaces _Tomodactylus nitidus petersi_. This is the only _Tomodactylus_ known to inhabit coastal lowlands.

~Tomodactylus nitidus petersi~ Duellman

_Tomodactylus petersi_ Duellman, Occ. Pap. Mus. Zool. Univ.

Michigan, 560:5, October 22, 1954.--Coalcoman, Michoacan, Mexico.

_Tomodactylus nitidus petersi_, Dixon, Texas Jour. Sci., 9:390, December, 1957.

Aguililla; Apatzingan (8); Cascada Tzararacua: Charapendo (5); Coalcoman (5); 18 km. E of Dos Aguas (6); El Sabino (5); La Playa (2); Jiquilpan; Uruapan (2); Volcan Jorullo; Zamora.

In life, specimens from Apatzingan (UMMZ 114308-9) varied in dorsal color from grayish tan to pale brown; the dorsal markings were olive green. The thighs and groin were yellowish orange; the iris was pale golden, and the vocal sac was purplish gray (Pl. 5, Fig. 1).

Measurements for 13 adult males from the Tepalcatepec Valley are: snout-vent length, 21.9-26.8 (24.3); tibia length, 8.4-9.9 (9.3); head width, 7.2-9.2 (7.8); head length, 7.6-8.7 (8.2).

At Apatzingan and Charapendo in the Tepalcatepec Valley males were found calling from rocks and bushes in open arid tropical scrub forest. The call, a triple note "peep-ee-eep," is repeated once every 90 to 135 seconds. _Tomodactylus nitidus petersi_ probably ranges throughout the Tepalcatepec Valley and surrounding foothills. Dixon (1957:392) referred the specimens from Zamora, Jiquilpan, and Uruapan to this subspecies.

Uruapan is near the lower limits of the pine forest on the slopes of the Cordillera Volcanica; Zamora and Jiquilpan are on a low part of the Mexican Plateau southeast of Lago de Chapala.

~Tomodactylus rufescens~ Duellman and Dixon

_Tomodactylus rufescens_ Duellman and Dixon, Texas Jour.

Sci., 11:78, March, 1959.--Dos Aguas, Michoacan, Mexico.

Dos Aguas (14); 18 km. E of Dos Aguas (6).

Fourteen specimens from the pine-oak forests around Dos Aguas (UMMZ 118503-10, 121498-9) have reddish brown dorsal color and a narrow cream-colored middorsal line (Pl. 5, Fig. 2). Twelve of these specimens are adult males having snout-vent lengths of 20.7 to 24.6 (22.5) mm. One female has a snout-vent length of 24.8 mm., and one juvenile has a snout-vent length of 14.5 mm. Six specimens are from a region of mixture of pine-oak forest and arid tropical scrub forest at 18 kilometers east of Dos Aguas (UMMZ 121497, 121500). All are males having snout-vent lengths of 18.0 to 22.6 (20.7) mm. The dorsum is tan marked with black; the thighs are yellowish orange.

The specimens from 18 kilometers east of Dos Aguas were found on July 22, 1960, by Floyd L. Downs and John Winklemann, who collected calling males of _Tomodactylus rufescens_ and _Tomodactylus nitidus petersi_ at the same locality. Downs (_personal communication_) stated the call was a single note. At Dos Aguas I heard _T. rufescens_ give two calls, one a single "peep," the other a triple note--"pee-ee-eep."

In the higher parts of the Sierra de Coalcoman _Tomodactylus rufescens_ seems to fill the same niche as _T. angustidigitorum_ does in the Cordillera Volcanica. At lower elevations in their respective mountain ranges the species occur sympatrically with _T. nitidus petersi_.

~Diaglena reticulata~ Taylor

_Diaglena reticulata_ Taylor, Univ. Kansas Sci. Bull., 28:60, May 15, 1942.--Cerro Arenal, Oaxaca, Mexico.

Nueva Italia (3); Ostula (7).

Until recently frogs of the genus _Diaglena_ were known only from a few specimens from southern Sinaloa (_Diaglena spatulata_) and from the Pacific lowlands of the Isthmus of Tehuantepec (_Diaglena reticulata_).

Peters (1955a) reported specimens from Ostula, Michoacan, and compared these specimens with one _D. reticulata_ from Tehuantepec, Oaxaca, and four _D. spatulata_ from Sinaloa. This comparison showed that the specimens from Michoacan, although showing some minor differences from _D. reticulata_, are closer to that species than to _D. spatulata_.

Subsequent to Peters' work, series of both species of _Diaglena_, including additional specimens from Michoacan and from Colima, have been collected, and a more qualified comparison is now possible.

In comparing specimens of _D. spatulata_ from southern Sinaloa (UMMZ 115322) with specimens of _D. reticulata_ from Tehuantepec, Oaxaca (UMMZ 115321), the differences noted by Taylor (1942c:60) were found to be constant. But specimens from Ostula, Michoacan (UMMZ 104418), and five individuals from Colima (TNHC 26379-83) were found to be intermediate in certain characters. The skin of the dorsum in _D. reticulata_ is granular; that in _D. spatulata_ is smooth. The skin in specimens from Ostula and Colima is slightly granular. The dorsal ground color of _D.

reticulata_ is yellowish brown with dark reticulations; the dorsal ground color of _D. spatulata_ is olive-green. Specimens from Ostula and Colima most closely resemble those from Tehuantepec in coloration, but the reticulations are more coa.r.s.e, and the ground color has an olive-green tint. _Diaglena reticulata_ also differs from _D.

spatulata_ in having a larger over-all size, slightly broader head, a narrower interorbital distance, and a more pointed snout with a deeper l.a.b.i.al shelf (Table 4). The specimens from Ostula and Colima are intermediate between _D. reticulata_ from Oaxaca and _D. spatulata_ from Sinaloa in body proportions.

Of three specimens from the Tepalcatepec Valley (JRD 5991-3), only two are suitable for measuring. These specimens are smaller than adults from the coastal areas and have broader heads and snouts, but narrower interorbital distances, than specimens in the other samples (Table 4).

The texture of the skin is like that of specimens from Ostula and Colima. The coloration resembles that of _D. reticulata_, but the reticulations are bold and form indistinct bands on the hind limbs.

TABLE 4.--COMPARISON OF FOUR CHARACTERS IN FIVE SAMPLES OF DIAGLENA.

(ALL DATA ARE FOR MALES; MEANS GIVEN IN PARENTHESES BELOW RANGES.)

+-----------------+---------+----------+----------+---------+-----------+ | | | | Head | Inter- |Internarial| | | | | width | orbital | distance | | | Number |Snout-vent| |distance | | | Locality | of | length |----------+---------+-----------+ | |specimens| |Snout-vent| Head | Head | | | | | length | width | width | +-----------------+---------+----------+----------+---------+-----------+ | Oaxaca | 9 |71.1-87.5 |25.4-29.1 |63.0-71.4| 11.9-13.8 | | | | (80.7) | (27.9) | (67.1) | (12.9) | +-----------------+---------+----------+----------+---------+-----------+ | Coast of | 5 |72.0-79.2 |24.3-27.2 |67.0-73.8| 13.7-14.4 | | Michoacan | | (74.8) | (25.6) | (71.4) | (14.1) | +-----------------+---------+----------+----------+---------+-----------+ | Colima | 4 |71.7-79.6 |26.1-28.6 |70.5-75.3| 16.0-17.9 | | | | (74.8) | (27.4) | (72.0) | (16.6) | +-----------------+---------+----------+----------+---------+-----------+ | Tepalcatepec | 2 |63.0-65.4 |28.3-32.2 |57.3-62.4| 17.0-20.2 | | Valley | | (64.2) | (30.3) | (59.9) | (18.6) | +-----------------+---------+----------+----------+---------+-----------+ | Sinaloa | 11 |71.9-81.3 |24.0-27.3 |70.5-78.1| 15.0-17.3 | | | | (77.3) | (25.7) | (73.4) | (16.1) | +-----------------+---------+----------+----------+---------+-----------+

All specimens from Michoacan and Colima more closely approach _Diaglena reticulata_ than _D. spatulata_. The acquisition of additional specimens, especially from the area between Sinaloa and Colima and from Guerrero, is necessary to determine the relationships among the various populations known at present. Both species of _Diaglena_ inhabit tropical scrub forest; none has been found in the more humid and tropical semi-deciduous forests. Humid forest replaces the scrub forest in the lowlands of southern Nayarit and northern Jalisco; possibly this forest acts as a barrier to the distribution of _Diaglena_ and thus serves as a divider between the ranges of _D. spatulata_ to the north and _D. reticulata_ to the south.

~Pternohyla fodiens~ Boulenger

_Pternohyla fodiens_ Boulenger, Ann. Mag. Nat. Hist., ser.

5, 10:326, 1882.--Presidio, Sinaloa, Mexico.

Nueva Italia (2).

These specimens (JRD 5994-5) were found on the road near Nueva Italia during a heavy rain on the night of August 25, 1960, by James R. Dixon.

Both are females having snout-vent lengths of 64.0 and 59.0 mm. They are typical of the species as it is known from Sinaloa, Nayarit, Jalisco, and Colima.