Brachiacantha tucumanensis Weise

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 : 47-48

38. Brachiacantha tucumanensis Weise

Brachyacantha tucumanensis Weise, 1910: 58 ; Korschefsky 1931: 207: Blackwelder 1945: 449.

Description. Male. Length 2.4 mm, width 1.6 mm; body elongate oval, convex. Dorsal surface with head alutaceous, dull, pronotum weakly alutaceous, slightly shiny, elytron weakly alutaceous, shiny. Color black except head yellow, pronotum yellow with small, oval mediobasal macula extended 2/3 distance to anterior pronotal margin, macula narrowly indented with yellow on apex, lateral 1/4 of pronotum yellow; elytron black with 5 small yellow spots, scutellar spot removed from scutellum, humeral spot long, slender, discal spot small, oval, obliquely angled, reddish yellow ( Fig. 218 ); ventral surface with antenna, mouthparts, legs yellow; abdomen dark brown. Head punctures small, separated by a diameter or less, each puncture about as large as an eye facet; pronotal punctures slightly larger than head punctures, separated by less than to twice a diameter, elytral punctures larger than on pronotum, separated by 1 to 2 times a diameter; metaventral punctures larger than on elytron, separated by a diameter or less medially, larger, separated by less than a diameter laterally. Clypeus emarginate apically, 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 without trace of bordering line medially. Epipleuron narrow, grooved, not descending externally, deeply emarginate for reception of femoral apices. Protibia narrowly flanged, flange less than width of remainder of protibia, outer margin straight, smooth, basal tooth small, length about 1/5 width of tibia at base, sponda not extended beyond protibial flange ( Fig. 219 ). Carinae on prosternal process narrowly separated at apex, slightly convergent toward base, not joined, ended at middle of prosternum. Metaventrite without setal tuft. Basal abdominal ventrite without setal tuft. Abdomen with postcoxal line on basal abdominal ventrite flattened along posterior ventrite margin, extended forward apically, ventrite with sparse, long pubescence and small, dense punctures; ventrites 2–6 pubescent throughout, punctures fine, dense; ventrite 3 without cusp on each side of middle; ventrites 3–5 depressed medially with tuft of setae on each side of emargination, 5th ventrite with apex broadly, deeply emarginate; 6th ventrite depressed medially, apex broadly emarginate. Apical tergite densely punctured, apex emarginate. Genitalia with basal lobe about as long as paramere, slender, symmetrical, sides slightly “pinched” at basal 1/3, widened in apical 2/3, sides rounded to acute apex, paramere short, weakly Psc, wide, twisted at base so paramere is at 45 degree angle, slender, sinuate in dorsal view, apex rounded ( Fig. 220. 221 ); sipho robust, strongly curved in basal 1/2, without visible lateral alae, basal capsule lightly sclerotized, inner arm short, narrow, apex broadly bifid, rounded, outer arm wider and longer than inner arm, with small accessory piece, basal border not emarginate ( Fig. 222, 223 ).

Female. Similar to male except head entirely black, pronotum with anterior border narrowly yellow, lateral border narrowly yellow. Genitalia with spermathecal capsule short, wide, widened from base to apex; bursal cap without sclerotized arms, apical strut short, base wide, apically slender ( Fig. 224 ).

Variation. Length 2.1 to 2.4, width 1.5 to 1.6 mm. Humeral spot on elytron often connected to mediolateral spot along lateral elytron margin, elytral spots variable in size, often larger than typical.

Type locality. Argentina, Province Tucuman.

Type depository. ZMHB (holotype).

Geographical distribution. Argentina, Salta.

Specimens examined. 8. Argentina. Province Salta ; Rosario del la Frontera, Salta ; Salta, Metan. ( JEBC) ( USNM) ( ZMHB)

Remarks. Brachiacantha tucumanensis is similar to several other Brachiacantha species in external appearance, but the scutellar spot is distinctly separated from the scutellum toward the humeral angle, and the elytral spots are usually very small. The discal spot is also unusual in that it is obliquely oval.

The holotype in the ZMHB is a female labeled “Rep. Argentina, Prov. Tucuman, 9.XI.1903, C. Bruch/ Brachiacantha tucumanen. m. (handwritten).” The abdomen, including genitalia, is missing from the holotype. Weise (1910) based his description of B. tucumanensis on a single specimen he had previously (1906) included under the name Hyperaspis scapulata Mulsant.

Figures

Figures 211–229. 211–217. Brachiacantha eleanor. 211) Habitus. 212) Protibia. 213) Phallobase ventral. 214) Phallobase lateral. 215) Sipho. 216) Enlarged siphonal apex. 217) Female genitalia. 218–224. Brachiacantha tucumanensis. 218) Habitus. 219) Protibia. 220) Phallobase ventral. 221) Phallobase lateral. 222) Sipho. 223) Enlarged siphonal apex. 224) Female spermathecal capsule and bursal cap. 225–229. Brachiacantha valerie. 225) Habitus. 226) Phallobase ventral. 227) Phallobase lateral. 228) Sipho. 229) Enlarged siphonal apex.