Sticholotis discoidea (Gorham)

Tomaszewska, Wioletta & Łączyński, Piotr, 2010, A contribution to Sticholotis Crotch from Myanmar (Coleoptera: Coccinellidae: Sticholotidini), Zootaxa 2658 (1), pp. 51-68 : 57-59

Sticholotis discoidea (Gorham)

( Figs. 3 , 27–43 )

Orcus discoideus Gorham, 1895: 688 .

Sticholotis discoideus: Weise, 1902: 512 .

Sticholotis discoidea: Łączyṅski & Tomaszewska, 2009: 610 .

Diagnosis. This species resembles externally S. carinica but can be separated by having smaller and less convex body, the elytral suture reddish brown, and the elytra very finely punctate.

Redescription. Length 2.5–2.8 mm; TL/EW = 1.1–1.2; PL/PW = 0.45–0.47; EL/EW = 0.85–1.00; GD/ TL = 0.6.

Body ( Figs. 3 , 27, 34 ) rounded, strongly convex; pronotal margins very narrow, visible from above; elytral margins moderately explanate, entirely visible from above. Head, pronotum and elytra along lateral and apical margins brownish black; scutellum infuscate; disk of elytron pale reddish brown; labrum dark reddish brown. Punctures on pronotum fine, 1.5–2.5 diameters apart; punctures on elytra very fine, 2.5–4.0 diameters apart; surfaces between punctures feebly microreticulate and shiny; dorsum apparently glabrous. Ventral surface dark reddish brown with hypomera, metepisterna, metepimera, inner part of elytral epipleuron, and abdominal ventrites along their lateral margins slightly lighter. Labial and maxillary palpi, antennae and tarsi yellowish brown.

Head ( Fig. 28, 30 ) flat medially, punctate and sparsely setose with short setae (more distinct anteriorly). Clypeus weakly arcuate anteriorly, scarcely reflexed along anterior margin. Eyes moderately large, coarsely faceted, dorsally separated by nearly 4.0 times eye width; interocular distance nearly 0.7 times head width; inner margins of eyes slightly sinuate, convergent anteriorly. Maxilla ( Figs 28, 31 ) with terminal palpomere almost 3.0 times longer than wide, subparallel along basal 2/3 of its length, strongly and obliquely truncate apically; labial terminal palpomere ( Figs. 28, 31 ) narrowed and acuminate, distinctly narrower than penultimate palpomere. Antenna ( Fig. 31 ) 11-segmented with narrow 3-segmented club.

Prothorax ( Fig. 30 ) about 0.88 times basal width of elytra; pronotum with groove extending along basal margin, disappearing laterally as it approaches hind angles; pronotal hypomeron and prosternum smooth; anterior lobe of prosternum distinctly bordered with anterior edge arcuate anteriorly; prosternal process ( Fig. 28 ) subtruncate at apex, without distinct lateral carinae, deeply and coarsely punctate near its apex and less coarsely near its base, punctures with long setae. Mesoventral intercoxal process ( Fig. 29 ) about 1.2 times mesocoxal diameter. Metaventrite with complete discrimen, rather finely punctate; postcoxal lines curved and complete. Elytral epipleuron ( Fig. 29 ) broad with maximum width at metaventrite, narrowing posteriorly but complete to apex, without distinct foveae. Wings well-developed.

Abdomen ( Figs. 32, 33 , 35 ) with 5 ventrites in both sexes; ventrite I along midline about 3.0 times longer than ventrite II; postcoxal line of first ventrite curved posteriorly and laterally, closely paralleling posterior margin, incomplete laterally; postcoxal disk microreticulate and distinctly punctate ( Fig. 36 ); ventrite V triangularly produced posteriorly and almost pointed at apex in female, regularly rounded in male. Male and female abdominal segment VIII as in Figs. 37, 39 .

Male genital segment with sternite IX triangular without apophysis ( Fig. 38 ). Male genitalia as in Figs. 42, 43 . Tegminal basal piece with distinct strut and additional, dorsal strut-like projection of about half length of proper strut; penis guide with additional, lateral lobes along apical half of its length; parameres long and thin with long setae at their apices; penis broad and flattened along apical third and with large capsule at base.

Female genitalia as in Figs. 40, 41 . Proctiger (T10) well developed. Ovipositor sclerotized; coxites elongate, entirely separated, densely setose apically; styli absent; spermatheca not observed.

Material examined. Types. Lectotype (here designated), male: “Carin Ghecu, 1300-1400 m, L. Fea, II- III.88./ Syntypus, Orcus ? discoideus Gorham, 1895 / Museo Civico di Genova ” ( MCSN) ; Paralectotypes: “Carin Ghecu, 1300-1400 m, L. Fea, II-III.88./ Gorham type/ Typus/ discoideus Gorh. / Orcus discoideus Gorh. / Orcus ? discoideus Gorh. typus!/ Syntypus, Orcus ? discoideus Gorham, 1895 / Museo Civico di Genova ” (2: MCSN) ; “Carin Asciuii Cheba, 1200-1300 m L. Fea. I-88./ Syntypus Orcus discoideus, Gorham, 1895 / Museo Civico di Genova ” (2: MCSN) ; “Carin Chebà, 900-1100 m., L. Fea V-XII-88/ Syntypus, Orcus discoideus Gorham / Museo Civico di Genova 1895” (1: MCSN) ; “Carin Ghecù / 1300-1400 m / L. Fea II- III.88/ 81884/ Cotype / Orcus discoideus Gorh. sp. n. ” (1: MNB) ; “Carin Ghecù/ 1300-1400 m. / L. Fea II- III.88/ Cotype ” (1: MNB) ; “Carin Chebà/ 900-1100. m./ L. Fea V XII-88/ Cotype ” (1: MNB) ; “Carin Chebà, 900-1100 m., L. Fea V-XII-88 (1: MIZ)” .

Note. In spite of formal transfer of Orcus discoideus to Sticholotis by Weise (1902), a lectotype has never been designated. The lectotype and paralectotypes for O. discoideus Gorham, 1895 , are designated here to fix the taxonomic status of this species.

Figures

FIGURES 1–5. Habitus, dorsal view; 1) Sticholotis bipunctata (Gorham); 2) Sticholotis quadriguttata (Gorham); 3) Sticholotis discoidea (Gorham); 4) Sticholotis dohrni Weise; 5) Sticholotis carinica (Gorham).

FIGURES 27–34. Sticholotis discoidea (Gorham); 27) body, dorsal view; 28) head, ventral and prosternal process; 29) body, ventral view; 30) head, prothorax and base of elytra, antero-dorsal; 31) antenna and mouthparts, ventral; 32) abdomen, female, ventral; 33) last abdominal ventrites, male; 34) body, lateral.

FIGURES 35–43. Sticholotis discoidea (Gorham); 35) abdomen, ventral; 36) abdominal postcoxal line; 37) abdominal segment VIII, male, ventral; 38) male genital segment, ventral; 39) abdominal segment VIII, female, ventral; 40) female genitalia, ventral; 41) coxite, ventral; 42) aedeagus, lateral; 43) aedeagus, inner.