The Amphibians and Reptiles of Michoacan, Mexico Part 19

_Elaphe triaspis intermedia_, Mertens and Dowling, Senckenbergiana, 33:201, November 15, 1952.

Twenty-four km. E of Apatzingan; Chupio; El Sabino (4); 11 km. E of Emiliano Zapata.

Dowling (1960) has shown that specimens from the Balsas-Tepalcatepec Basin have fewer ventrals and caudals than those from the Sierra del Sur or the coast. All specimens from Michoacan were collected in open forest, either scrub or oak forest. They were found in drier situations than those described for the species in southern Tamaulipas by Martin (1958:69). In Michoacan _Elaphe triaspis intermedia_ is known from the Tepalcatepec Valley, the lower slopes of the Cordillera Volcanica, and the western edge of the Mexican Plateau at an elevation of 1350 meters.

It probably occurs in the lower parts of the Sierra de Coalcoman and along the Pacific coast, for it is known from the coastal lowlands of Guerrero and Colima. In August, 1951, I saw a snake that probably was this species in Barranca de Bejuco.

~Enulius unicolor~ (Fischer)

_Geophis unicolor_ Fischer, Abh. Nat. Ver. Bremen, 7:227, 1882.--Mexico. Type locality restricted to Chilpancingo, Guerrero, Mexico, by Smith and Taylor (1950a:331).

_Enulius unicolor_, Taylor and Smith, Univ. Kansas Sci.

Bull., 25:247, July 10, 1939.

Between Ario de Rosales and La Playa; Coalcoman; Jungapeo (4); between Zitacuaro and Tuxpan.

This small snake has been collected from beneath rocks in brushy areas and broad-leafed forest between 900 and 1800 meters; it has not been found in coniferous forest. The limited ecological data suggest that the species inhabits the transition zone between the tropical scrub forest and the temperate hardwood forest.

All of the specimens have 17 rows of scales; four males have 169-178 (174.2) ventrals and 102-111 (106.8) caudals; two females have 192 and 195 ventrals and 96 and 87 caudals. Three individuals have one postocular on one side and two on the other; in the other specimens there are two postoculars on each side. The largest male has a body length of 232 mm. and a tail length of 130 mm.; the largest female has a body length of 274 mm. and a tail length of 119 mm.

~Geagras redimitus~ Cope

_Geagras redimitus_ Cope, Jour. Acad. Nat. Sci.

Philadelphia, ser. 2, 8:141, 1876.

San Juan de Lima (2).

Previously this species was known definitely only from the Plains of Tehuantepec, Oaxaca. _Sphenocalamus lineolatus_ was described by Fischer (1883:5) from Mazatlan; this name has been placed in the synonymy of _Geagras redimitus_ Cope. Although Fischer gave the type locality only as "Mazatlan" and did not designate the state, it is probable that the type originated from Mazatlan, Sinaloa. The present specimens are from a locality almost midway between Tehuantepec and Mazatlan and support the possibility that _Geagras_ ranges along the Pacific coast of Mexico from Oaxaca to Sinaloa.

The two specimens from Michoacan (UMMZ 114446-7), both males, have 118 and 122 ventrals, 31 and 33 caudals, body lengths of 108 and 81 mm., and tail lengths of 20 and 15 mm. Both have 1-1 preoculars, 1-1 postoculars, 1-2 temporals, 6-6 upper l.a.b.i.als, and 5-5 lower l.a.b.i.als. In life, the dorsum was pale tan; the top of the head and the middorsal and lateral stripes were dark brown; the belly was white. The occipital spots were pale pinkish tan. Both specimens were found beneath rocks in tropical semi-deciduous forest at an elevation of 15 meters on the coastal plain.

~Geophis dugesi~ Bocourt

_Geophis dugesii_ Bocourt, Miss. Scientifique au Mexique et dans l'Amerique Centrale, Rept., livr. 9:573, 1883.--Tangancicuaro, Michoacan, Mexico.

Carapan; Tangancicuaro; Zacapu.

Aside from the three specimens listed above, there are two (SU 4407-8) bearing the data "Michoacan." Bocourt (1883:574) stated that the type specimen from Tangancicuaro had six or seven pale cross-bands on the anterior part of the body. An ill.u.s.tration, presumably of the same specimen, by Duges (1884:Pl. 9) shows five distinct and one indistinct cross-bands. Of the four specimens that I have examined, none has more than three pale cross-bands, and one has only one indistinct cross-band.

Two females have 154 and 158 ventrals and 38 and 37 caudals; two males have 150 and 151 ventrals and 43 and 42 caudals.

This species is known only from elevations between 1750 and 2050 meters on the southwestern edge of the Mexican Plateau in the state of Michoacan.

~Geophis incomptus~ Duellman

_Geophis incomptus_ Duellman, Occ. Pap. Mus. Zool. Univ.

Michigan, 605:3, May 29, 1959.--Dos Aguas, Michoacan, Mexico.

Dos Aguas (15).

This species, which seems to be related to _Geophis maculiferus_, is known only from the pine-oak forest in the vicinity of Dos Aguas (elevation 2100 meters) in the Sierra de Coalcoman. Aside from the five specimens comprising the type series, there are ten other specimens in the Museum of Zoology at the University of Michigan collected by Floyd L. Downs in July, 1960. Data from these specimens and those comprising the type series show that in this sample seven males have 146-153 (149.3) ventrals and 35-37 (36.0) caudals; eight females have 150-154 (152.4) ventrals and 29-34 (32.5) caudals. The largest specimen is a female with a body length of 344 mm. and a tail length of 53 mm.

~Geophis maculiferus~ Taylor

_Geophis maculiferus_ Taylor, Univ. Kansas Sci. Bull., 27:119, December 30, 1941.--Near Cicio [_sic_] = Tzitzio, Michoacan, Mexico.

Tzitzio.

The type and only known specimen of _Geophis maculiferus_ (UIMNH 25078) is a female having 140 ventrals and 30 caudals, dorsal scales in 15 rows, one postocular, and an anterior temporal. Only one other species in Mexico has dorsal scales in 15 rows and has an anterior temporal; that species is _G. incomptus_, which differs from _G. maculiferus_ in having six or seven lower l.a.b.i.als, instead of five, and in having the edges of the ventrals dark, instead of a uniformly cream-colored belly.

The locality from which the specimen was obtained lies at an elevation of 1630 meters on the southern slope of the Cordillera Volcanica. At that elevation there is an interdigitation of arid tropical scrub forest and pine-oak forest; probably _Geophis maculiferus_ inhabits the pine-oak forest.

~Geophis nigrocinctus~ Duellman

_Geophis nigrocinctus_ Duellman, Occ. Pap. Mus. Zool. Univ.

Michigan, 605:1, May 29, 1959.--Dos Aguas, Michoacan, Mexico.

Dos Aguas (3).

The three specimens comprising the type series of the species were found beneath logs and in a stump in pine-oak forest at an elevation of 2100 meters. A discussion of the variation in these specimens and of probable relationships of the species was given by Duellman (1959).

Floyd Downs spent several days at Dos Aguas in July, 1960; although he found ten specimens of _Geophis incomptus_, no further specimens of _G.

nigrocinctus_ were obtained.

~Geophis petersi~ Boulenger

_Geophis petersii_ Boulenger, Catalogue Snakes... British Museum, 2:321, September 23, 1894.--Mexico City. Type locality restricted to Patzcuaro, Michoacan, Mexico, by Smith and Taylor (1950a:335).

Cheran; Coalcoman; Morelia; Patzcuaro (6).

This seems to be the most widespread species of _Geophis_ in Michoacan.

It has been found at elevations between 950 and 2350 meters, chiefly in pine or pine-oak forest. Boulenger (1894:321) described _Geophis petersi_ from a specimen stated to be from Mexico City, a locality which probably is in error. The only localities from which the species is definitely known are those listed in this account.

Three males and five females from the Mexican Plateau and the Cordillera Volcanica have respectively 140-144 (141.7) and 143-151 (146.0) ventrals and 39-41 (40.0) and 29-35 (33.2) caudals. All have dorsal scales in 15 rows, 1 postocular, no anterior temporal, and a relatively small triangular supraocular. The specimen from Coalcoman (UMMZ 104698) was referred to _Geophis nasalis_ by Peters (1954:22). This specimen is abnormal in several characters; in five places there is a fusion and separation of the vertebral and paravertebral scale rows, producing a change from 17 to 15 rows of dorsal scales. Fusion of the three rows takes place at the level of the 8th, 41st, 47th, 54th, and 65th ventrals. Furthermore, there is a small secondary postocular on each side of the head. In other characters the specimen is like _G. petersi_; the resemblances to that species are greater than to _G. nasalis_, which has been recorded from Guatemala and southern Chiapas.

~Geophis tarascae~ Hartweg

_Geophis tarascae_ Hartweg, Occ. Pap. Mus. Zool. Univ.

Michigan, 601:1, May 4, 1959.--Uruapan, Michoacan, Mexico.

Uruapan (3).

A female of this species was collected in the Parque Nacional at the north edge of Uruapan in 1899, and a male was taken there in 1947; these specimens were used by Hartweg in his description of the species. Floyd L. Downs obtained another specimen in the Parque Nacional on July 19, 1960. It has 164 ventrals and 46 caudals; in life, the ground color of the neck was brown with a purplish tint; the dorsal markings were black; the chin was a cream-color, and the belly was white. This specimen is distinguished from those of all other species of _Geophis_ in Michoacan in that it has dark irregular cross-bars on the dorsum and a row of dark spots on the venter.