Brachinus lateralis Dejean, 1831

Erwin, Terry L., 1965, A Revision Of Brachinus Of North America: Part I. The California Species (Coleoptera: Carabidae), The Coleopterists Bulletin 19 (1), pp. 1-19 : 7-8

Brachinus lateralis Dejean

Brachinus lateralis Dejean, 1831: 424 .

Brachynus leucoloma Chaudoir, 1868: 301 . ( NEW SYNONYMY)

TYPE LOCALITY: B. lateralis : "Moritz, Angustura, Guayama baja, Misiones Del Coronis" is handwritten on the label of Mannerheim's specimen, which was given to him by Dejean; B. leucoloma : "de Rio Gila, en California" is cited in Chaudoir's description (refers to the Gila River in the extreme southeast corner of California).

TYPE SPECIMENS: One syntype of B. lateralis is in the Mannerheim collection at the University of Helsinki. One cotype of B. leucoloma is in the Museum National d'Histoire Naturelle, Paris.

DISTRIBUTION: This species is widely distributed across the southern United States from Florida to California and into Mexico. Blatchley (1910) records one specimen from Indiana, but the record is doubtful because he indicates the elytra are blue-black instead of brown ( fig. 12 ).

DESCRIPTION: Size. Length 7 to 9 mm.; width 4.3 to 4.5 mm. Coloration. Elytra of both sexes brownish with pale testaceous epipleura; head and pronotum dark ferrugineus; mandibles piceous at apex; antennal segments 1-4, legs, palpi, and frons ferrugino-testaceous; antennal segments 5-11 dark ferrugineus; mesepisterna and sides of abdominal sterna dark brown (similar in color to the elytra). Head. Labrum slightly notched at apex; dorsal surface of mentum convex with a seta at each anterior corner; bead occurs only around top half of eyes; frons with rugose longitudinal furrows which widen at base of clypeus; only a few setae arise behind eyes and on top of head; microsculpture consists of small isodiametric meshes. Pronotum.

Slightly wider just before middle and with sides deeply sinuate; anterior angles not very prominent (barely exceeding width of anterior margin); posterior angles prominent, acute with lateral basal impressions almost absent; lateral margins slightly reflexed, narrowly beaded with dark reddish brown bead; disc flat, slightly rugose down midline and with a few setiferous punctures at base and at midapex; microsculpture consists of small isodiametric meshes. Elytra. Male elytra truncate, widest at apical third, narrowing anteriorly to prominent humeri; very slightly costate; microsculpture consists of very fine isodiametric meshes; pubescent bands occur near humeri only in 7th and 8th intervals, but broadened gradually and covering entire elytra beyond apical sixth. Female elytra similar, but proportionately slightly wider than those of male in apical half. Aedeagus ( fig. 3 ). Phallus heavily sclerotized ending in a blunt tip; a median dorsal ridge and two lateral ridges occur near apex and the apical half is rugose between ridges; microsculpture lacking. Endophallus bears a poorly pigmented virga consisting of two lateral plates.

CALIFORNIA LOCALITY RECORDS: 94 specimens were examined. Imperial County: (Yuma) CAS, (Salton Sea) VVB, (Mecca) Coachella Valley Mosquito Abatement District Collection, (Calpatria) CAS, (El Centro) CAS; Los Angeles County: (Pasadena) CAS, (Long Beach) CAS, (Lake Hodges) SDNHM, (Cypress) LACM, (Los Angeles) CAS; Orange County: (Laguna Canyon) ATM, (Anaheim) SDNHM; Riverside County: (Elsinore) CAS, (Elsinore Lake) CAS UIM, (Blythe) UIM LACM, (Corona) ATM; San Bernadino County: (Needles) CAS, (Ontario) CAS, (Saratoga Springs, Death Valley) ATM; San Diego County: (Oceanside) CAS, (San Diego) SDNHM, (San Juan Capistrano) UIM, (Sweetwater Valley) SDNHM.

DERIVATION OF THE NAME: French, lateralis - side; referring to the pale epipleura.

DISCUSSION: This species is very easy to recognize because it is the only North American species with brown elytra. The aedeagus is also very distinctive.

Figures

FIGURES 10-13, Brachinus spp. California distribution maps.

FIGURES 1-9, Brachinus spp. Aedeagus from dorsal and