Brachiacantha bistripustulata (Fabricius)

Gordon, Robert D., Canepari, Claudio & Hanley, Guy A., 2014, South American Coccinellidae (Coleoptera), Part XVI: systematic revision of Brachiacantha Dejean (Coccinellinae: Hyperaspidini), Insecta Mundi 2014 (390), pp. 1-76 : 10-11

1. Brachiacantha bistripustulata (Fabricius)

Coccinella bistripustulata Fabricius, 1801: 383 .

Brachyacantha bis-tripustulata: Mulsant, 1850: 528.

Brachyacantha bistripustulata: Gorham 1894: 188 ; Casey 1899: 119; Leng 1911: 296; Korschefsky 1931: 203; Blackwelder 1945: 449.

Brachyacantha bistripustulata var. guttata Weise, 1885: 231 ; Korschefsky, 1931: 203.

Brachyacantha bistripustulata ab. decora Casey, 1899: 119; Korschefsky 1931: 203.

Brachyacantha bistripustulata var. quichiana Leng, 1911: 290 ; Korschefsky 1931: 204.

Brachyacantha bistripustulata var. minor Leng, 1911: 290 ; Korschefsky 1931: 203.

Brachyacantha bistripustulata var. obscura Leng, 1911: 290 ; Korschefsky 1931: 204.

Brachiacantha bistripustulata: Milléo and Almeida 2007: 420 .

Description. Male. Length 3.3 mm, width 2.6 mm; body oval, convex. Dorsal surface with head strongly alutaceous, dull, pronotum and elytron slightly alutaceous, shiny. Color yellow except pronotum with narrow, black mediobasal macula extended 3/4 distance to anterior pronotal margin, macula apically entire; elytron black with 4 yellow spots, humeral spot small, triangular, remaining spots large, irregularly shaped ( Fig. 1 ); ventral surface with head, prosternum, meso- and metaventrite black; abdomen dark brown except apices of ventrites 4–5 brownish yellow. Head punctures small, separated by a diameter or less, each puncture about as large as an eye facet; pronotal punctures larger than head punctures, separated by a diameter or less, elytral punctures larger than on pronotum, separated by less than to twice a diameter; metaventral punctures as large as on elytron medially, separated by a diameter or less, coarser, separated by less than a diameter toward lateral margin. Clypeus weakly emarginate apically, nearly truncate, lateral angle rounded, surface with sparse, long pubescence. Eye canthus about 6 eye facets long, angled forward, apically rounded, yellow. Pronotum narrowed from base to apex, basal and anterior angles abrupt, lateral margin weakly rounded, basal margin with trace of bordering line medially. Epipleuron narrow, grooved, slightly descending externally, deeply emarginate for reception of femoral apices. Protibia narrowly flanged, flange narrower than remainder of protibia, outer margin curved, smooth, basal tooth large, longer than 1/2 width of tibia at base, sponda extended beyond protibial flange, apically rounded. Carinae on prosternal process narrowly separated at apex, slightly convergent toward base, not joined, ended at base of process. Metaventrite without setal tuft. Basal abdominal ventrite without setal tuft. Abdomen with postcoxal line on basal abdominal ventrite slightly flattened along posterior ventrite margin, extended forward at apex, ventrite with dense, long pubescence and small, dense punctures; ventrites 2–6 pubescent throughout, punctures fine, dense; ventrite 3 with large, flat, apically acute cusp on each side of middle; 5th ventrite depressed medially, apical margin broadly, strongly emarginate; 6th ventrite short, narrow, depressed medially, apical margin broadly emarginate. Apical tergite finely, densely punctured, apex convex. Genitalia with basal lobe long, 4/5 as long as paramere, asymmetrical, sides convergent from base to apex, apex abruptly bent to one side; paramere wide, curved, not Psc, with large, apically acute angulation before apex, apex rounded ( Fig. 2, 3 ); sipho robust, strongly curved in basal 1/2, lateral alae present at apical 3/4, basal capsule large, heavily sclerotized, inner arm short, wide, apex abruptly rounded, outer arm about as wide and longer than inner arm, with small accessory piece, basal border deeply emarginate ( Fig. 4, 5 ).

Female. Similar to male except head yellow with apex of yellow area semicircular, clypeus black, black area narrowly extended posteriorly along inner eye margin, pronotal macula extended to apical margin of pronotum, apex of macula widened, elytron without humeral spot. Genitalia with spermathecal capsule short, slender, narrowed from base to apex; bursal cap oval, with 3 arms, apical strut long, wide, flattened in lateral view ( Fig. 6 ).

Variation. Length 3.0 to 4.5 mm, width 2.4 to 2.8 mm. Elytron with yellow maculae somewhat variable in size, shape, and arrangement. Size and shape vary considerably, and males often have the humeral and mediolateral spots narrowly connected.

Type locality. Not determined.

Type depository. ZMUC.

Geographical distribution. Mexico south through Central and South America to Brazil and Peru, and also known from Cuba and Jamaica.

Specimens examined. 87. This species is commonly collected and numerous in collections.

Remarks. Brachiacantha bistripustulata is an unusual element in the South American fauna. It belongs to a group of species well represented in North America containing such species as B. dentipes (F.), B. tau LeConte , etc., but is the only member of this group known from South America. It is probable that B. bistripustulata should be considered a member of Brachiacantha , and all others with symmetrical male genitalia placed in a new genus.

It is the most frequently seen species of Brachiacantha in all collections examined.

Figures

Figures 1–17. 1–6. Brachiacantha bistripustulata. 1) Habitus. 2) Phallobase ventral. 3) Phallobase lateral. 4) Sipho. 5) Enlarged siphonal apex. 6) Female genitalia. 7–12. Brachiacantha buckleyi. 7) Habitus. 8) Phallobase ventral. 9) Phallobase lateral. 10) Sipho. 11) Enlarged siphonal apex. 12) Female spermathecal capsule. 13–17. Brachiacantha charlotte. 13) Habitus. 14) Phallobase ventral. 15) Phallobase lateral. 16) Sipho. 17) Enlarged siphonal apex.