Cassida flavosignata Spaeth, 1932

Borowiec, Lech & Świętojańska, Jolanta, 2022, A monograph of the Afrotropical Cassidinae (Coleoptera: Chrysomelidae). Part 6. Revision of the tribe Cassidini 3, the genus Cassida L., Zootaxa 5171 (1), pp. 1-250 : 67-68

Cassida flavosignata Spaeth, 1932

( figs. 13 , 122–123)

Cassida flavosignata Spaeth, 1932: 236 ; Borowiec, 1999: 252.

Cassida flavolsignata [sic]: Nummelin & Borowiec, 1991: 14.

Description. L: 4.30–4.60 mm, W: 3.80–4.00 mm, Lp: 1.50–1.60 mm, Wp: 2.70–2.95 mm, L/W: 1.13–1.18, Wp/ Lp: 1.74–1.97. Body almost circular (fig. 122).

Pronotal disc black, explanate margin yellow. Scutellum black, sometimes with paler spot centrally. Elytral disc black with yellow, slightly elevated spots of irregular borders: one large on each side of scutellum, two very small at apex of scutellum, three in row on each side of suture, middle spot distinctly smaller than first and third spot, one obliquely to basal spot and one in 2/3 length of rows 4–6. Yellow are also part of marginal interval below humerus, lateral fold, apical part of second interval and apex of disc. Explanate margin uniformly yellow (figs. 122, 123). Head yellow, sometimes basal corners brown, prosternum brown, metasternum and abdomen yellow. Fore and mid coxa infuscate but rest of legs yellow. Antennal segments 1–7 yellow, apical segments brown to black.

Pronotum elliptical, with maximum width in the middle, anterior margin regularly convex, sides broadly rounded, no basal corners, lateral lobes well marked, bordered from explanate margin by short impressions anteriorly and posteriorly. Surface of disc shiny, with very fine pricks. Explanate margin broad, impunctate, shiny, transparent with well visible honeycomb structure.

Base of elytra much wider than base of pronotum, humeral angles distinctly protruding anterad, angulate. Disc regularly convex in profile (fig. 123), with shallow postscutellar principal impressions and indistinctly marked H–shaped elevation. Punctation moderately coarse arranged in completely regular rows, dense, distance between punctures from slightly narrower to slightly wider than puncture diameter. Marginal row distinct, its punctures not coarser than punctures in central rows. Intervals shiny, mostly flat, only second interval between yellow elevated spots slightly convex, in sutural part of disc intervals approximately as wide as rows, on sides linear, marginal and submarginal interval slightly wider than rows. Marginal interval slightly narrower than submarginal one, with short humeral and lateral folds. Explanate margin broad, slightly declivous, in the widest part three times narrower than disc, surface shiny with shallow punctation, appears slightly irregular, transparent with well visible honeycomb structure.

Eyes extremely large, gena obsolete. Clypeus narrow, approximately 1.1 times as long as wide. Clypeal grooves indistinct, run close to margins of eye, converging in angle, surface of clypeus flat or very shallowly impressed, shiny, impunctate. Labrum narrowly emarginate to 1/5 length. Antennae moderately slim, segments 9–10 approximately as long as wide. Length ratio of antennal segments: 100:64:71:71:75:50:50:46:50:54:121. Segment 3 approximately 1.5 times as long as segment 2 and approximately 1.2 times as long as segment 4.

Prosternum broad in the middle, strongly expanded apically, area between coxae impressed medially, shiny, without special sculpture, expanded apex flat with several small punctures and short grooves, appears slightly irregular.

Claws with small basal tooth.

Distribution. Eastern Democratic Republic of Congo, Rwanda, and N Tanzania ( fig. 13 ).

Remarks. A member of the Cassida flavosignata species–group. It differs from two other members of the group, Cassida benguelica and C. leleupi , in pronotal black spot solid, without two small yellow spots inside (with two spots in both relatives), elytral punctation more coarse and more regular with rows only slightly disturbed by yellow relief (less regular and strongly disturbed by yellow relief in both relatives) and marginal interval predominantly black (almost completely yellow in both relatives).

Types examined. Holotype: [ TANZANIA]: Usambara , 1930, Staudinger ( MM).

Other specimens examined. DEMOCRATIC REPUBLIC OF CONGO (ZAIRE): Kivu, Lulenga, 23 XI 1925, 1, H. Schouteden ( MRAC) .

RWANDA: Cyangugu Prov. , Nyakabuye, 1–15 V 1983, 1, 23 II 1984, 2, H. Mühle ( MD) .

TANZANIA: Usambara , Derema, 850 m, 30 VIII–15 IX 1891, 2, Conradt ( MNHW) .

Figures

FIGURE 13. Distribution of Cassida delenifica (black squares), Cassida flavosignata (black circles) and Cassida elgonensis (black diamond).