Birds from Coahuila, Mexico

by Emil K. Urban

*Myiarchus crinitus crinitus (Linnaeus).—Specimens examined: total 3: ♀ 32065 from 12 mi. N, 12 mi. W Jiménez, 850 ft., June 19, 1952; and ♂ 32066 and ♀ 32067 from 2 mi. W Jiménez, 850 ft., June 20, 1952.

The Great Crested Flycatcher seems to be rare in Coahuila. Nos. 32065-32067 are the first specimens that I know of from Coahuila. Bangs (1898:179-180) said that the subspecies crinitus has an "enormous swollen bill" (exposed culmen of male, 20 mm.; breadth of bill at middle of nostril, 10.3 mm.) whereas M. c. boreus has a "small slender bill" (exposed culmen of male, 18.6 mm.; breadth of bill at middle of nostril, 8.6 mm.). No. 32066 has a large bill (exposed culmen, 21 mm.; breadth of bill at middle of nostril, 10 mm.). Bangs (loc. cit.) did not give any measurements for females of M. c. crinitus or boreus. Nevertheless, I suspect that Nos. 32065 and 32067 represent crinitus (No. 32065: exposed culmen, 19 mm.; breadth of bill at middle of nostril, 9 mm.; No. 32067: exposed culmen, 20 mm.; breadth of bill at middle of nostril, 9.5 mm.). The size of the testes (9 mm. long) of No. 32066 and the dates (June 19 and 20) on which the specimens were collected indicate breeding by this species in the State.

*Myiarchus tyrannulus cooperi Baird.—Specimens examined: total 2: ♂ 32068 and ♀ 32069 from 2 mi. S, 3 mi. E San Juan de Sabinas, 1160 ft., June 22, 1952, measurements: wing, 102, 97 mm.; tail, 93, 90 mm.

Wied's Crested Flycatcher is not common in Coahuila. Eastern Coahuila represents the eastern limit of the range of M. t. cooperi. Measurements of our specimens agree well with the average measurements of typical M. t. cooperi. According to Ridgway (1907:621), M. t. cooperi (then called Myiarchus mexicanus mexicanus) has been recorded from Sabinas. The size of the testes (14×7 mm.) of No. 32068 and the date (June 22) on which the specimens were collected indicate breeding by this species in the State.

*Myiarchus cinerascens cinerascens (Lawrence).—Specimens examined: total 7: ♀ 31045 from 15 mi. SE Boquillas, 1500 ft., March 16, 1952; ♂ 32070 from 12 mi. N, 12 mi. W Jiménez, 850 ft., June 19, 1952; ♀ 32071 from 2 mi. W Jiménez, 850 ft., June 20, 1952; ♂ 35413 from 6 mi. N, 2 mi. W Castillón, 3750 ft., June 30, 1953; ♂ 32072 from 9 mi. S, 11 mi. E Sabinas, June 14, 1952; ♀ 31584 from 17 mi. S Ocampo, 5300 ft., April 7, 1954; and ♂ 31673 from the west foot of Pico de Jimulco, 5000 ft., April 4, 1953.

The Ash-throated Flycatcher is common in Coahuila. All specimens examined by me from there are typical of M. c. cinerascens. Ridgway (1907:626) listed M. c. cinerascens from Monclovia (=Monclova?) and Sabinas. Miller (1955a:166) found the species "only in the oak belt at 5000 feet, where it was common." Burleigh and Lowery (1942:193) recorded M. c. cinerascens from "near Saltillo." Dickerman obtained No. 31584 in a mesquite-grassland-shrubby area. Miller, Friedmann, Griscom, and Moore (1957:78) stated that M. c. cinerascens breeds in Coahuila.

Sayornis phoebe (Latham).—Miller, Friedmann, Griscom, and Moore (1957:66) recorded the Eastern Phoebe from Coahuila on November 4-14.

*Sayornis nigricans semiatra (Vigors).—Specimens examined: total 2: ♀ 31046 from 1 mi. N Boquillas, 700 ft., March 7, 1952; and ♀ 31047 from Fortín (=33 mi. N, 8 mi. W San Gerónimo), 3300 ft., March 27, 1952.

Of the Black Phoebe, the two subspecies semiatra and nigricans intergrade in Coahuila. Typical representatives of S. n. semiatra are present in northern Coahuila. The under tail coverts of Nos. 31046-31047 are immaculate and white. Miller (1955:167) noted the two specimens collected from the Sierra del Carmen to have narrow dark shaft streaks on the under tail coverts. He (loc. cit.) remarked also that "the marking of the under tail coverts may indicate a beginning of a gradient in increased darkening of these feathers toward S. n. nigricans in southern Coahuila."

*Sayornis nigricans nigricans (Swainson).—Burleigh and Lowery (1942:193) collected several specimens of S. n. nigricans "on the outskirts of Saltillo" and saw a pair at the Chorro del Agua on April 19.