Chiridopsis ruandana Spaeth, 1934

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 : 54-55

Chiridopsis ruandana Spaeth, 1934

( figs 15 , 29, 30 )

Chiridopsis ruandana Spaeth, 1934 b: 392 ; Borowiec, 1999: 303.

Description. Le: 4.80–5.10 mm, Wi: 3.40–3.45 mm, Lp: 1.60–1.80 mm, Wp: 2.90–2.95 mm, Le/Wi: 1.41–1.48, Wp/Lp: 1.64–1.81.

Dorsum uniformly yellow ( figs 29, 30 ). Head black. Thorax black, abdomen black, narrowly surrounded by yellow. Coxae from brown to black, trochanters brown, rest of legs yellow, sometimes extreme base of femora infuscate. Antennae yellow, last antennal segment more or less infuscate.

Pronotum irregularly elliptical ( fig. 29 ), with maximum width in the middle, anterior margin softly convex, sides moderately rounded, no basal corners. Surface of disc shiny, with very fine and sparse pricks. Explanate margin broad, impunctate, shiny, transparent with well visible honeycomb structure.

Base of elytra slightly wider than base of pronotum ( fig. 29 ), humeral angles distinctly protruding anterad, subrounded. Disc moderately convex in profile ( fig. 30 ), on top of slightly depressed, without impressions. Punctation moderate, on sides coarser than on top of disc, arranged in regular rows, mostly sparse, distance between punctures from two to five times wider than puncture diameter. Marginal row distinct, its punctures slightly coarser than punctures in central rows. Intervals flat, from slightly alutaceous to shiny, on top of disc three to four, on sides two to three times wider than rows, second interval in posterior half twice wider than first and third intervals, marginal interval in humeral part 2.5 times wider than submarginal one, no humeral or lateral folds. Explanate margin very narrow, strongly declivous, almost perpendicular to abdominal surface, in the widest part 7.5–8.0 times narrower than disc, surface with very shallow, sparse punctures or impunctate, appears regular, shiny, semitransparent to transparent with more or less visible honeycomb structure.

Eyes very large, gena obsolete. Clypeus broad, 1.4 times as wide as long. Clypeal grooves deep, running mostly parallel to inner margin of eye then converging in arch, surface of clypeus moderately convex, microreticulate but shiny with distinct median line and few very small, setose punctures. Labrum minutely emarginate to 1/7 length. Antennae stout, segments 9–10 slightly wider than long. Length ratio of antennal segments: 100:50:64:61:50:46:57:50:54:50:111. Segment 3 approximately 1.3 times as long as segment 2 and approximately as long as segment 4.

Prosternum broad in the middle, moderately expanded apically, area between coxae flat, impunctate, shiny, with few small punctures, expanded apex flat, shiny, with few irregular impressions.

Claws with small basal tooth, last segment of tarsi with projecting dentiform flanks thus claws appear strongly dentate.

Distribution. Ruanda ( fig. 15 ).

Remarks. Chiridopsis ruandana ( figs 29, 30 ) belongs to the group of species with completely yellow dorsum and black clypeus. The group comprises also Ch. flavipennis , Ch. observabilis ( figs 56–61 , 111, 112 ), yellow form of Ch. aubei ( fig. 39 ) and rare form of Ch. convexula ( figs 27, 28 ) with brown to black clypeus. The last species distinctly differs in elytral rows of punctures tending to form pairs (1+2, 3+4, 5+6, 7+8) and interval 2 and 4 distinctly wider than intervals 1 and 3, while in other species elytral rows of punctures are spread more or less regularly over elytral surface. Three first species differ in stouter, short-oval to subcircular body with moderately declivous explanate margins, length/width ratio 1.24–1.30 and explanate margin of elytra broad, as wide as 3–4 lateral intervals combined, while in Ch. ruandana body is elongate-oval, almost parallel-sided with strongly declivous explanate margins, length/width ratio 1.41–1.48, and explanate margin of elytra narrow, only twice wider than two lateral intervals combined.

Types examined. Lectotype and paralectotype: [ RWANDA] Gabiro, 1932, A. Verhulst (lectotype MRAC, paralectotype MM).

Other specimen examined. RWANDA: Astrida env., 1955, 1 ( DBET).

Figures

FIGURE 15. Distribution of Chiridopsis picturata (black squares), Chiridopsis quadriguttata (black circles), Chiridopsis ruandana (white square) and Chiridopsis spadix (white circles).

FIGURES 24 – 30. Chiridopsis aequinoctialis. 24. Male dorsal, 25. Female dorsal, 26. Female lateral; 27 – 28. Chiridopsis convexula. 27. Dorsal, 28. Lateral, 29 – 30. Chiridopsis ruandana. 29. Dorsal, 30. Lateral.

FIGURES 56 – 61. Chiridopsis observabilis. 56 – 58. Form described as Ch. observabilis, 56. Male dorsal, 57. Female dorsal, 58. Female lateral; 59 – 61. Form described as Ch. athinia, 59. Male dorsal, 60. Female dorsal, 61. Female lateral.

FIGURES 107 – 114. Chiridopsis parellina. 107. Dorsal, 108. Lateral, 109 – 110. Chiridopsis regionalis. 109. Dorsal, 110. Lateral; 111 – 112. Chiridopsis flavipennis. 111. Dorsal, 112. Lateral; 113 – 114. Chiridopsis zambiana. 113. Dorsal, 114. Lateral.

FIGURES 37 – 42. Chiridopsis aubei. 37 – 38. Form described as ab. signaticollis, 39. Form described as ab. baumanni, 40 – 42. Form described as ab. dissoluta.