Chiridopsis opposita ( Boheman, 1854 )

Świ, Jolanta, 2017, A monograph of the Afrotropical Cassidinae (Coleoptera: Chrysomelidae). Part 4. Revision of the genus Chiridopsis Spaeth, Zootaxa 4316 (1), pp. 1-85 : 46-48

Chiridopsis opposita ( Boheman, 1854)

( figs 14 , 87–89 )

Cassida opposita Boheman, 1854: 461, 1857: 141 , 1862: 343; Gemminger and Harold, 1876: 3656.

Chirida opposita: Weise, 1896 c: 23 ; Spaeth, 1914: 127.

Chiridopsis opposita: Spaeth, 1924: 352 ; Shaw, 1968 a: 371, 1972: 78; Borowiec, 1985 a: 241, 1986: 807, 1999: 301.

Coptocycla lorata Boheman, 1862: 419 ; Gemminger and Harold, 1876: 3671; Spaeth, 1924: 352 (as synonym of Cassida opposita ).

Chirida lorata: Weise, 1896 c: 23 ; Spaeth, 1914: 127.

Description. Le: 5.0–6.2 mm, Wi: 4.3–5.9 mm, Lp: 1.9–2.2 mm, Wp: 3.0–3.6 mm, Le/Wi: 1.13–1.25, Wp/Lp: 1.55–1.67.

Pronotum yellow ( figs 87, 88 ), disc with black base, and large, black M–shaped figure often marked with small yellow spot anteriorly and small yellow spot on each side, in some specimens black figure very thin then small yellow frontal and lateral spots joined with yellow background. Scutellum completely black or black with yellow centre. Elytral disc in typical form yellow with black suture, black stripes around disc and black band across middle thus elytra appear black with four large yellow to orange spots, two in anterior and two in posterior half of disc. Marginal interval in anterior 2/3 length black. In pale forms black pattern thin and stripes surrounding disc with yellow spots below humeral callus and in mid length. Head, ventrites, legs, and antennae yellow, apex of last antennal segment more or less infuscate.

Pronotum elliptical ( figs 87, 88 ), with maximum width in the middle, anterior margin regularly convex, sides broadly rounded, no basal corners. Surface of disc impunctate, shiny. Explanate margin broad, impunctate, shiny, transparent with well visible honeycomb structure.

Base of elytra much wider than base of pronotum ( figs 87, 88 ), humeral angles distinctly protruding anterad, subangulate. Disc slightly unevenly convex in profile ( fig. 89 ), more convex in postscutellar area, with very shallow postscutellar impressions. Punctation very fine, on sides coarser than on top of disc, arranged in regular rows, punctures in rows sparse, distance between punctures mostly from two to five times wider than puncture diameter. Marginal row distinct, its punctures distinctly coarser than punctures in central rows. Intervals flat, on top of disc five to seven times, on sides three to four times wider than rows, marginal interval 1.2–1.5 times wider than submarginal one, no humeral or lateral folds. Explanate margin broad, moderately declivous, in the widest part 4.5–5.0 times narrower than disc, surface impunctate, shiny, transparent with well visible honeycomb structure.

Eyes very large, gena obsolete. Clypeus broad, approximately 1.3 times as wide as long. Clypeal grooves fine but well marked, converging in regular triangle, surface of clypeus distinctly convex, shiny with few very small, setose punctures and sometimes with impressed median line. Labrum minutely emarginate to 1/6 length. Antennae slim, segments 9–10 approximately 1.5 times as long as wide. Length ratio of antennal segments: 100:42:50:78:64:53:56:56:58:61:111. Segment 3 approximately 1.2 times as long as segment 2 and approximately 0.6 times as long as segment 4.

Prosternum broad in the middle, strongly expanded apically, area between coxae more or less impressed, surface regular but sometimes with short and shallow transverse grooves but shiny, with few setose punctures, expanded apex flat, without special sculpture or only slightly irregular, shiny, with few setose punctures.

Claws with moderate basal tooth, last segment of tarsi with projecting flanks of apex, dentiform.

Host plants. Convolvulaceae : Merremia hederacea (E. Obermaier in litt. after Borowiec & Świętojańska 2016), Ipomoea batatas (L.) Lam. (label data).

Distribution. West Africa east to N Republic of Congo ( Zaire) ( fig. 14 ).

Remarks. Chiridopsis opposita belongs to the group of species in which elytral black reticulation forms only stripes along sides and a band across middle of disc, thus elytra have only with four large yellow spots. Chiridopsis opposita and Ch. boutareli are the only such coloured species with ventrites uniformly yellow ( figs 43–45 , 87–89 ). Chiridopsis boutareli differs in broad elytral band, narrowest in the lateral connection and broadest in the sutural part but with posterior narrow yellow emargination along sutural connection, sometimes the yellow emargination complete thus band narrowly twice interrupted along suture or black band broadened and closed two small yellow spots near suture while in Ch. opposita elytral band is thin to moderately broad, approximately equal width in lateral and sutural connection with lateral and sutural stripes. At first glance very similar pattern has the palest form of Ch. nigrosepta ( figs 74–76 ) but differs in ventrites partly black.

Types examined. Holotype of Cassida opposita : Senegal, Buquet ( ZMHU).

Type of Coptocycla lorata not examined (preserved probably in BMNH).

Other specimens examined. BENIN: Zagnanado, 3 ( ZMHU).

BURKINA FASO: Haute Volta, Melou , 45 ( IRSN, DBET).

DEMOCRATIC REPUBLIC OF CONGO ( ZAIRE): Garamba Nat. Park, Mande , 5 IV 1950, 1, de Saeger ( MRAC).

GHANA: Asente Akem, Ashantis, 1, Junod ( MRAC) ; Ashante, 3, Simon ( ZMHU) ; Ashanti Region, Kumasi, Nhiasu , 330 m, 30 IX 1967, 1, S. Endrödy-Younga ( DBET) ; Ashanti Region, Kumasi, Bobiri Forest , 5 VIII 1960, 5 (4 BMNH, 1 LS) ; Ashanti Region, Kumasi , 26 VII 1960, 3 (2 BMNH, 1 LS); Takoradi, 3 (2 MRAC, 1 DBET) ; Wenchi road, 3l mls. N of Kumasi , 18 IX 1973, 1, R. Linnavuori ( ZMUH) .

GUINEA: Guinea , 1 ( ZMHU) ; Kindia , 20–26 IV 1964, 1, 10–16 V 1964, 1, 15–30 VI 1964, 1, Šabacký (LS); Pastoria, 13 X 1984, 1, S.W. Murzin ( SMNS) .

IVORY COAST: Abengourou , 16 VIII 1961, 2, J. Decelle ( MRAC) ; Assinie, 1 (MRAC); Comoé, XII 1995, 4, from Merremia hederacea, E. Obermaier (EO); Danane et env., IV 1910, 8, A. Chevalier ( MNHN) ; Dimbroko, 12 (IRSN, LS, NMP, DBET); Eremankono, S Diro , II 1962, 1, J. Decelle ( MRAC) .

NIGERIA: Apeji, U. C. Ibadan, on Ipomoea batatas , 28 VIII 1 952, 7, 8 IX 1952, 1, G. H. Caswell (6 BMNH, 2 LS); Enugu, 31 X 1955, 1, J. Bechyně ( NHMB) ; Ibadan , 1 II 1914, 1, W. A. Lamborn ( BMNH) ; Minna , 20 VIII 1975, 1, W. Bogatko ( DBET) .

SENEGAL: Badoumbé , I–V 1882, 4, Nodier ( DBET) ; Senegal, 3 ( MRAC, DBET), 1 ( ZMHU), 1, Kraatz ( ZMHU) .

SIERRA LEONE: Giema , 8 VIII 1912, 1, J. J. Simpson ( BMNH) ; Mayemba, 1 (NMP); Sierra Leone, 1 ( MRAC) .

TOGO: Bismarckburg, 1, L. Conradt ( ZMHU); Kolokope, 1 VII 1990, 1 on Ipomoea batatas, P. Silvie (HPA).

Figures

FIGURE 14. Distribution of Chiridopsis opposita (black circles) and Chiridopsis parellina (white circles).

FIGURES 87 – 93. Chiridopsis opposita. 87. Male dorsal, 88. Female dorsal, 89. Female lateral; 90 – 91. Chiridopsis octoguttata. 90. Dorsal, 91. Lateral; 92 – 93. Chiridopsis subornata, black form. 92. Dorsal, 93. Lateral.

FIGURES 43 – 49. Chiridopsis boutareli. 43. Male dorsal, 44. Female dorsal, 45. Female lateral; 46 – 47. Chiridopsis castaneoplagiata. 46. Dorsal, 47. Lateral, 48 – 49. Chiridopsis circe. 48. Dorsal, 49. Lateral.

FIGURES 74 – 79. Chiridopsis nigrosepta. 74. Male dorsal, 75. Female dorsal, 76. Female lateral, 77 – 79. Variation of dorsal pattern (79. Form described as ab. vernicata).