1840. D[esmodus]. murinus Wagner, in Schreber, Die Säugthiere ..., Suppl., 1:337, type from México.
1912. Desmodus rotundus murinus, Osgood, Field Mus. Nat. Hist., Publ. 155, Zool. Ser., 10:63, January.
Distribution in Tamaulipas.—Southern part of state, north at least to vicinity of Jiménez.
Hall and Kelson (1959:151) listed a place 12 kilometers west and 8 kilometers north of Ciudad Victoria as the northernmost locality of record for Desmodus, but three specimens from Cueva La Esperanza, 6 kilometers southwest of Rancho Santa Rosa, are from a site slightly to the northwestward (12 mi.) of the locality first mentioned and a specimen from 13 miles west and six and a half miles north of Jiménez represents the northeasternmost known occurrence of Desmodus in eastern México.
Most of the vampires examined in this study were taken in caves; those from four miles southwest of Padilla were obtained from a hollow tree. Nine specimens were collected in a small cave 70 kilometers south of Ciudad Victoria on January 18, when water on the floor of the cave was frozen; the bats were congregated on the ceiling at a height of 20 feet. In a cave in the Sierra de Tamaulipas, 16 miles west and three miles south of Piedra, females and young were found some 50 yards from the entrance; Natalus stramineus and Glossophaga soricina were obtained from the same cave. In another cave only half a kilometer distant, 12 males were collected. In Cueva La Mula, Desmodus was found near the mouth, whereas Choeronycteris mexicana and two Tadarida brasiliensis were collected in the deepest part. At Cueva La Esperanza, 300 feet deep and on the east side of the Sierra Madre Oriental, four different congregations of vampires were found along with about 400 Natalus. A male Desmodus obtained in a cave 13 miles west and six and a half miles north of Jiménez also was associated with Natalus.
Females with embryos or in lactation were collected as follows: Rancho Pano Ayuctle, March 10, one pregnant female (embryo 40 mm. in crown-rump length); Río Sabinas, May 23, two pregnant females (embryos 36 and 43 mm.); Sierra de Tamaulipas, June 13, five lactating females and one female taken alive that gave birth on June 16 to one young; Cueva La Mula, August, nine lactating females. A male from the Sierra Madre that was obtained on January 5 had testes 8 mm. long.
The average weight of 21 adults from four miles southwest of Padilla was 39.1 (32.0-44.5) grams.
Records of occurrence.—Specimens examined, 107: 3 mi. W, 6.5 mi. N Jiménez, 1250 ft., 1; Río Soto la Marina, 4 mi. SW Padilla, 800 ft., 23; Cueva La Esperanza, 6 km. SW Rancho Santa Rosa, 360 m., 3; Cueva Los Troncones, 8 km. N, 12 km. W Cd. Victoria, Sierra Madre Oriental, 2500 ft., 2; Cd. Victoria, 1; Sierra Madre Oriental, 1900 ft., 5 mi. S, 3 mi. W Cd. Victoria, 3; La Mula, 13 mi. N Jaumave, 19; Cueva La Mula, 10 km. W Joya Verde, 2400 ft., 16; Joya Verde, 35 km. SW [Cd.] Victoria, 3800 ft., 6; Sierra de Tamaulipas, 1400 ft., 3 mi. S, 16 mi. W Piedra, 10; 70 km. S Cd. Victoria (via Highway), 6 km. W of Highway, 5; Rancho Pano Ayuctle, 6 mi. N Gómez Farías, 300 ft., 7; cave near headwaters Río Sabinas, 10 km. N, 8 km. W El Encino, 400 ft., 11.
Additional records (Malaga and Villa, 1957:539): Cueva La Sepultura, 7.5 km. NNW and hence 7 km. SSW (via highway) Cd. Victoria; El Ojo de Agua, at km. 10 on Valles-Tampico highway; Cueva del Abra, 2 km. SSW Cd. Mante.