Dilatitibialis silvani (Crotch) Canepari, Claudio, Gordon, Robert D. & Hanley, Guy A., 2013

Canepari, Claudio, Gordon, Robert D. & Hanley, Guy A., 2013, South American Coccinellidae (Coleoptera), Part XV: systematic revision of Dilatitibialis Duverger (Coccidulinae; Hyperaspidini), Insecta Mundi 2013 (312), pp. 1-91 : 33-34

23. Dilatitibialis silvani (Crotch) , new combination

Hyperaspis silvani Crotch, 1874: 214 ; Korschefsky 1931: 197; Blackwelder 1945: 448; Gordon 1987: 27.

Description. Male. Length 2.7 mm, width 2.3 mm; body rounded, convex. Dorsal surface shiny, lacking alutaceous sculpture. Color yellow except pronotum with narrow, basomedian, dark brown macula extended anteriorly beyond middle of pronotum on each side; elytron with suture and 4 spots dark brown, dark area along suture widened slightly on apical declivity, discal spot rectangular, connected to suture, humeral spot irregularly round, inner spot on apical declivity narrow, elongately oval, lateral spot on apical declivity narrow, elongate, irregularly oval ( Fig. 123 ); ventral surface with head, prosternum, meso- and metaventrites dark brown; abdomen mostly yellowish brown except lateral 1/4 paler brownish yellow. Head punctures small, separated by a diameter or less, as large as or slightly larger than an eye facet; pronotal punctures slightly larger than head punctures, separated by less than to twice a diameter; elytral punctures as large as on pronotum, separated by less than to twice a diameter; metaventral punctures larger than on elytron, separated by less than a diameter medially, becoming larger and separated by less than a diameter toward lateral margin. Clypeus weakly emarginate apically, lateral angle rounded, surface with sparse, long pubescence. Eye canthus about 6 eye facets long, curved, apically rounded, yellow. Pronotum narrowed from base to apex, basal and anterior angles abrupt, lateral margin straight, basal margin without bordering line. Epipleuron narrow, grooved, slightly descending externally, deeply emarginate for reception of femoral apices. Protibia narrowly flanged, flange narrower than remainder of protibia, outer margin weakly rounded, smooth, sponda slightly extended beyond protibial flange. Carinae on prosternal process narrowly separated at apex, convergent nearly to base, joined just before base with single carina extended to basal margin of prosternum. Metaventrite without setal tuft. Basal abdominal ventrite without setal tuft. Abdomen with primary pores laterally between ventrites 4- 5 small, extended under apical 1/4 of ventrite 4; postcoxal line on abdominal ventrite rounded, extended to apical margin of ventrite at middle, slightly flattened along margin, then broadly forward, ventrite with sparse, long pubescence and dense, coarse punctures medially; ventrites 2-4 sparsely pubescent throughout, punctures small, dense; 5th ventrite depressed medially at apex, long pubescence on each side of median depression, without tubercle on each side of middle, apical margin broadly emarginate, surface nearly impunctate; 6th ventrite short, narrow, depressed medially, apical margin broadly emarginate, sparsely pubescent on each side of median depression, surface nearly impunctate. Apical tergite densely punctured, pubescent, apical border weakly rounded. Genitalia with basal lobe 5/6 as long as paramere, asymmetrical, triangular in outline, apex bluntly rounded; paramere Psc, similar to the scimitar-like paramere typical of Brachiacantha species , narrowed ( Fig. 124, 125 ); sipho robust, strongly curved in basal 2/3, basal capsule large, inner arm short, narrowed at middle, apex feebly emarginate with lateral projections, outer arm as wide as inner arm, slightly longer than inner arm, with accessory piece, basal border widely emarginate ( Fig. 126, 127 ).

Female. Similar to male except head with vertex dark brown on each side at base of eye, pronotum with basomedian macula large, extended medially nearly to anterior pronotal margin, deeply, narrowly emarginate with yellow at middle. Genitalia with spermathecal capsule short, wide, narrowed in apical 1/ 2; bursal cap narrowly oval, with 3 distinct arms, apical strut long, robust ( Fig. 128 ).

Variation. Length 2.0 to 2.8 mm, width 1.6 to 2.4 mm. Elytral color pattern varies from the typical described above to having all dark spots narrowly connected, forming 2 transverse, very irregular bands, or further fused forming a nearly all dark surface with scattered, small yellow spots

Type locality. Brazil.

Type depository. UMZC (holotype, examined).

Geographical distribution. Brazil.

Specimens examined. 53. Brazil. Distributed throughout much of southern and eastern Brazil. ( CAS) ( CMNH) ( DZUP) ( GGC) ( USNM).

Remarks. Specimens of D. silvani are easily recognized if they possess the typical dorsal color pattern. If that pattern is suffused into a mostly dark surface with small, yellow spots, then genitalia must be used to aid in recognition.

This is a highly variable species. For example, most of a series from Ilha da Vitória, Sao Paulo, Brazil, has a dark elytral background with small, scattered yellow spots. However, some specimens in that series exhibit the typical D. silvani color pattern.

Figures

Figures 118-134. 118-122) Dilatitibialis crystal. 118) Habitus. 119) Phallobase ventral. 120) Phallobase lateral. 121) Sipho. 122) Enlarged siphonal apex. 123-128) Dilatitibialis silvani. 123) Habitus. 124) Phallobase ventral. 125) Phallobase lateral. 126) Enlarged siphonal apex. 127) Sipho. 128) Female genitalia. 129-134) Dilatitibialis gladys. 129) Habitus. 130) Phallobase lateral. 131) Phallobase ventral. 132) Enlarged siphonal apex. 133) Sipho. 134) Female genitalia.