Brachinus favicollis Erwin, NEW SPECIES

TYPE LOCALITY: Jamul, San Diego County, California.

TYPE SPECIMENS: The holotype male and allotype female have been deposited in the entomological museum at the California Academy of Sciences in San Francisco. Both were collected by F. E. Blaisdell at

the type locality, on March 20, 1899. Seventy-six paratypes collected on various dates and at various localities are indicated in the CALIFORNIA LOCALITY RECORDS and they have been returned to the museums also indicated there.

DISTRIBUTION: This species is restricted to southern California and possibly Mexico. It occurs sympatrically with B. lateralis in the latter's western-most range (fig. 15).

DESCRIPTION: Size. Length 9.5 to 10.5 mm.; width 4.5 to 4.8 mm. Coloration. Elytra of both sexes blue with a violaceous cast and epipleura blue; head and pronotum ferrugineus to brown; mandibles red-brown with piceous mesal edges; antennal segment 1 and legs ferrugineus; antennal segments 2-11 and palpi ferrugineusbrown; mesepisterna black; sides of abdominal sterna ferrugineus to brown. Head. Labrum emarginate, with yellow lateral edges; dorsal surface of the mentum slightly convex with a seta at each anterior corner; bead around eyes entire but finer at antennal base; frons with deep frontal furrows which are rugose and punctate; numerous setae arise behind eyes and on top of head; microsculpture consists of very fine isodiametric meshes. Pronotum. Widest at apical third and with sides moderately sinuate; anterior angles not prominent; posterior angles acute with lateral basal impressions shallow; lateral margins somewhat reflexed with a narrow bead of slightly darker color than pronotum; disc flat with many deep punctures forming a very rugose surface and with many setiferous punctures scattered over entire surface; microsculpture consists of small isodiametric meshes. Elytra. Male elytra truncate, widest at apical third, narrowing slightly to humeri which are not prominent; deeply costate; microsculpture consists of small isodiametric meshes; pubescent bands occur in each interval from humerus to apex. Female elytra similar, but proportionately wider and flatter than those of male in apical third. Aedeagus (fig. 6). Phallus cylindrical and ending in a blunt point; with apical sixth twisted very slightly; microsculpture lacking. Endophallus bears a lightly pigmented bilobed virga which is fused apically.

CALIFORNIA LOCALITY RECORDS: 76 paratypes were examined. Los Angeles County: (Pasadena) CAS, (San Francisquito Canyon) LACM, (Los Angeles) LACM, (Azusa) LACM, (Tujunga Creek) LACM; Orange County: (Black Star Canyon) ATM; Riverside County: (Hemet) VVB, (Palm Canyon) LACM, (Palm Springs) ATM; San Bernadino County: (Mojave River) CAS; San Diego County: (Jamul) CAS, (Pamo Valley) LACM, (Mission Valley) SDNHM.

DERIVATION OF THE NAME: Latin, favus _ honeycomb; collis neck; referring to the strongly punctured thorax of members of this species.

DISCUSSION: This species is one of four whose members have pubescence covering the entire elytra. The deeply punctate pronotum is a good field recognition character.