Stilbocoris triangularis Linnavuori, 1978

Kondorosy, Előd & Zámbó, András, 2021, The genus Stilbocoris in the Malagasy area (Hemiptera: Heteroptera: Rhyparochromidae), Zootaxa 5047 (4), pp. 416-430 : 424

Stilbocoris triangularis Linnavuori, 1978

urn:lsid:zoobank.org:act:B579CFD3-000F-4446-BE2C-013B7346AA62

( Fig. 3 )

Type locality. Sudan, Blue Nile Province, Umm Banein Livestock Research Station .

Examined material. MADAGASCAR: N. Madagascar, Antseranana /distr., Sambirana riv./ Marovato VIII., 2001/ J. Rolčik leg. 5-12.12 (2 ♀♀, EKCH) ; N. Madagascar / Antseranana distr. / Sambirana riv./ Marovato vill., 2001/ J. Rolčik leg. 5-12.12 (1 ♀, 1?, EKCH) ; Madagascar Sambirano /Nosy-Be/forêt de Lokobe /XII-58/ Andria Rob- inson/ Institut / Scientifique / Madagascar (1 ♀, MNHN) . SENEGAL: Senegal-Casamance / Kamobeul-Essyhl / 30-IX- 1982 / J. Etienne Rec. [blue label]//sur fruits/tombes/ de Ficus vogeli [blue label]// Museum Paris [light blue label] (1 ♀, MNHN) . TANZANIA: Tanzania , Morogoro / light trap, 20. V. 1970 /leg. T. Pócs (1 ♀, HNHM) .

Redescription. Colour. Body fuscous; basi- and distiflagellum and callar area continuing posteriad in midline brown; scape, pedicel, labium, pronotum (except fuscous nearly triangular area mostly on anterior lobe not reaching margins), lateral part of ostiolar peritreme, proepimeron and metepimeroid (except punctures), legs with supracoxal lobes, 2–2 almost rounded spots on abdominal sternite III and IV (but sometimes almost all of abdominal sternites nearly uniformly paler in middle part) and sometimes posterior part of mesosternum narrowly pale brown; hemelytra (except fuscous apical margin of corium) pale yellow; membrane hyaline.

Integument. Body shiny except sublateral pruinose spot of abdominal sternite V almost reaching anterior margin of sternite leaving posterior one-fourth free. Head finely coriaceous, densely punctate with small but deep punctures dorsally, ventral part of head with similar or slightly coarser punctures.Anterior lobe of pronotum densely punctate with fine punctures (similar to punctures of head) almost touching each other, callar area with somewhat finer punctures; posterior lobe in anterior half rather sparsely, in posterior half more densely punctate with slightly coarser punctures; humeral angles glabrous. Anterior part of scutellum with fine punctures similar to that of head but sparser, mostly also transversely rugose, elevation impunctate, punctures laterad of carina very coarse, almost confluent. Punctures of hemelytra variable from very shallow to similar of head punctures. Thoracal venter very densely and coarsely punctate, also metepimeroid punctate. Abdominal venter finely and densely punctate with extremely tiny punctures.

Vestiture. Head almost glabrous dorsally except extremely short decumbent setae of antenniferous tubercles; with scattered semidecumbent setae on tylus, maxillar plates and ventrally. Pronotum with some hardly visible scattered very short erect setae. Profemora each armed with 2 short thick and dark subapical spines ventrally, meso- and metafemora unarmed ventrally. Abdomen with fine decumbent pubescence.

Structure. Labium reaching mesocoxae, labiomere I surpassing anterior three quarters of head length but not reaching base of head. Ventral side of head with strong longitudinal wrinkle from inner margin of antenniferous tubercles to posterior margin, missing from other Stilbocoris species of the region but present on S. natalensis and its relatives. Callar area of pronotum hardly emergent. Transverse impression of pronotum nearly absent. Lateral margin of pronotum hardly laminate, less than half as wide as base of pedicel; concave at middle, posterior margin clearly concave. Scutellum with well-developed Y shaped elevation.

Male genitalia. Male of this species is still unknown. It is very unusual that neither among the types nor among the additional material examined (further specimens were seen in the studied collections which were not listed above) not a single male has been found. Parthenogenesis has not been reported from any members of Drymini , but it might occur in this species.

Total length of body: 3.54–4.26.

Distribution. This species was previously known only from the type locality in Sudan; first records are presented here from Senegal, Tanzania and Madagascar ( Fig. 10 ).

Figures

FIGURE 10. Distribution of Stilbocoris species in Madagascar.

FIGURES 1–4. Dorsal views of Stilbocoris species: 1. Stilbocoris solivagus Bergroth, 1893, 2. Stilbocoris galla Linnavuori, 1978, 3. Stilbocoris triangularis Linnavuori (Photos: authors), 1978 4. Stilbocoris scudderi sp. nov. paratype, dorsal view (Photo: Csaba Pintér).