Cassida calvaria ( Weise, 1900 )

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 : 39-41

Cassida calvaria ( Weise, 1900)

( figs. 7 , 75–77 )

Odontionycha calvaria Weise, 1900: 215 .

Cassida (Cassida) calvaria: Spaeth, 1914 b: 118 .

Cassida calvaria: Borowiec, 1999: 241 .

Description. L: 4.90–5.00 mm, W: 3.95–4.10 mm, Lp: 1.60–1.65 mm, Wp: 2.95–3.05 mm, L/W: 1.22–1.25, Wp/ Lp: 1.84–1.85. Body almost circular ( figs. 75, 76 ).

Pronotum yellow in anterior half and brown in posterior half, the brown occupies also basal part of explanate margin. The dark spot is not colcolour but forms some paler coloured, yellowish to yellowish brown areas especially on top of disc and in front of scutellum. Scutellum yellow to yellowish brown, ground colour of elytral disc yellowish brown to brown with paler coloured, yellowish wrinkles, yellow part of marginal row below humerus, yellow lateral fold and yellow apical part of marginal interval. In pale forms postscutellar tubercle and posterior tubercles partly or completely yellowish, in dark forms the tubercles dark brown. Explanate margin yellow, in typical form with broad brown humeral and posterolateral spots, humeral spot extending to anterior margin of elytra and only humeral spine is yellowish ( fig. 76 ). In pale form pattern of the explanate margin forms semicircular figure, inside with large fenestrate yellow spot, humeral angle largely yellow ( fig. 75 ). Head, ventrites and legs yellow. Antennae yellow only apical segment partly infuscate.

Pronotum elliptical, with maximum width behind the middle, anterior margin regularly convex, sides broadly rounded, no basal corners. Area above head slightly impressed, lateral lobes well marked, distinctly bordered from explanate margin by deep impression. Surface of disc shiny, with fine and very sparse punctation. Distance between punctures several times wider than puncture diameter, interspaces smooth. Explanate margin broad, impunctate, shiny, yellow part transparent with well visible honeycomb structure.

Base of elytra much wider than base of pronotum, humeral angles distinctly protruding anterad, margin of elytra behind humeral angle shallowly emarginate thus angles spiniform. Disc convex, strongly sculptured, with high postscutellar tubercle and high tubercles in posterior 2/3 length of the second interval ( fig. 77 ), area between postscutellar and posterior tubercles, sides of disc and slop with several longitudinal and transverse folds or wrinkles, in dark coloured specimens the sculpture stronger than in pale coloured forms. Punctation coarse and dense, distance between punctures mostly smaller than puncture diameter. Punctures tend to form regular rows but the regularity is disturbed by elytral relief, especially on top of disc. Marginal row distinct, its punctures approximately twice coarser than punctures in central rows, interspaces convex, form short folds. Intervals when visible then slightly narrower than rows, marginal interval well marked, especially in anterior half, in humeral part twice wider than lateral intervals, no humeral fold but distinct lateral fold. Explanate margin broad, slightly declivous, in the widest part three times narrower than disc, surface with some impressions, with shallow, but coarse and dense punctation, appears irregular, only yellow parts transparent with well visible honeycomb structure. Entire surface of elytra shiny.

Eyes very large in male slightly larger than in female, gena obsolete. Clypeus narrow, in female slightly longer than wide, in male 1.3 times as long as wide. Clypeal grooves fine but well marked, run close to margin of eye, converging in arch or obtuse angle, surface of clypeus shallowly impressed on entire length or only on apex, its surface shiny, without punctures. Labrum narrowly emarginate to 1/5 length.Antennae slim, segments 9–10 elongate, 1.2–1.3 times as long as wide. Length ratio of antennal segments: 100:55:73:61:64:55:55:55:58:55:127. Segment 3 approximately 1.3 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 flat without special sculpture, central part of expanded apex slightly convex, shiny, without sculpture, lateral parts impressed with irregular surface.

Claws with large basal tooth.

Host plant. Amaranthaceae : Achyranthes aspera L. var. pubescens (Moq.) Towns ( Heron 2016) ; Pupalia lappacea (L.) Juss. (H. Heron letter inf.).

Distribution. Eastern Democratic Republic of Congo, Uganda, Tanzania and Zambia ( fig. 7 ).

Remarks. A very distinct species with no close relatives in the African fauna. It is recognized by the dorsal pattern with dark, brown to almost black patches on pronotal disc, base of pronotal explanate margin, humeral and posterolateral spots on elytral explanate margin sometimes coalescent with central, yellow fenestral spot, more or less dark elytral disc combined with a distinct postscutellar hump, and short, elevated, elongate folds on the slope of disc ( figs. 75, 76 ). Both humeral and posterolateral dark spots on elytral explanate margin are found only in Cassida tarda (figs. 83, 84) and C. vespertilio (fig. 136) but both differ in elytral disc without a postscutellar hump and without folds on the elytral slope. A large, dark humeral spots on the elytral explanate margin and spots at the base of the pronotal margin combined with mostly dark elytral and pronotal discs is found in C. rogozinskii ( fig. 107 ) but this species differs in the absence of posterolateral spots on the elytral explanate margin, the elytral disc behind scutellum only slightly convex, without hump, and slope of elytral disc without elongate folds. The darkest forms of C. guttipennis ( fig. 161 ) have a mostly dark anterior part of elytral explanate margin with yellow fenestral spot, but they differ in the elytral disc regularly convex without a postscutellar hump and without elongate folds on the slope.

Type examined. Holotype: [ TANZANIA]: Mombo , VII 1899 ( ZMHU).

Other specimens examined. DEMOCRATIC REPUBLIC OF CONGO ( ZAIRE): Albert Nat. Park, Secteur Nord, Ngokoi affl., Talya, 1080 m, 1, P. Vanschuytbroeck ( MNHW).

SOUTH AFRICA: Natal , Palmiet Nat. Res., Westville, 29°49’S, 30°56’E, 1 ( HH) ; Natal , Paradise Valley Nat. Res., Pinetown, 29°49’54’’S, 30°53’30’’E, 1 ( HH) ; Natal , Nagle Dam , Umgeni Valley, near Cato Ridge, 29°35’S, 30°37’E, 1 ( HH) .

UGANDA: Bwamba , 7 VIII 1946, 1, Van Someren ( BMNH) .

ZAMBIA: Livingstone , 29 XII 1991, 1 ( MNHW) .

Figures

FIGURE 7. Distribution of Cassida calvaria (black circles) and Cassida camerunensis (black diamonds).

FIGURES 75–77. Cassida calvaria. FIGURES 78–79. Cassida satanas. 75–76, 78. Dorsal; 77, 79. Lateral.

FIGURES 107–108. Cassida rogozinskii. FIGURES 109–110. Cassida setosa. 107, 109. Dorsal; 108, 110. Lateral.

FIGURES 158–161. Cassida guttipennis. 158, 160–161. Dorsal; 159. Lateral.