Rugosothynnus brunneus, Brown, Graham, 2015

Brown, Graham, 2015, Rugosothynnus gen. nov. (Hymenoptera: Tiphiidae: Thynninae: Rhagigasterini), a newly recognised Australian genus, Zootaxa 3925 (3), pp. 361-386 : 363-364

Rugosothynnus brunneus sp. nov.

( Figs 11–13 , 17 )

Diagnosis. Male. Vertex and dorsum of mesosoma rugose; S1 sagittally carinate; S2 anteromedially subtuberculate; cuspis branched in profile with ventral lobe directed ventrally and about twice as long as dorsal lobe. Female. Brown, almost concolorous with indistinct yellowish-orange macula about eye size mesad to eye ventrally.

Description. Male. Head. Rounded, not emarginate posteriorly, produced and subparallel behind eyes; clypeus truncate, convex with inverted Y-shaped carina, depressed below branches, closely punctate laterally and basally, polished and sparsely punctate apically; antennal prominence with V-shaped carina, produced below carina to antennal insertions; frons weakly transversely carinate, discontinuous medially, sagittally carinate to mid ocellus, depressed below transverse carina; vertex rugose; gena rugosely punctate.

Mesosoma . Pronotum as wide as head, rugose, anterior margin weakly emarginate, carinate, acutely produced laterally; mesoscutum rugose; tegulae rugosely punctate basally; mesoscutellum rugose, weakly convex, subtriangular, rounded posteriorly; metanotum rugose, below level of mesoscutellum; propodeum oblique posteriorly, not transversely carinate, rugose to rugosely punctate anteriorly, transversely rugosely punctate posteriorly; fore coxae punctate; mesopleura rugose.

Metasoma. T1–6 closely punctate anteriorly, sparsely punctate posteriorly; S1 rugosely punctate, S2–7 closely punctate; gradulus straight and impunctate on T2–6, weakly curved and scrobiculate on S3–5, obscure on S6, absent on S7; T1 truncate anteriorly, subtuberculate above truncation; S1 medially raised and carinate; S2 anteromedially subtuberculate; hypopygium with angulate basal angles; cuspis bifid in profile with ventral lobe directed ventrally and about twice as long as dorsal lobe; paracuspis short.

Colour. Black; ocellar macula orange; wings hyaline.

Length. Body 18–19 mm; fore wing 11–12 mm; hind wing 8–9 mm.

Female. Head. Subrectangular, posterior angles rounded; clypeus truncate, sagittally carinate; frons longitudinally rugosely punctate, obscurely sagittally sulcate; vertex longitudinally rugosely punctate, not medially depressed; gena closely punctate; eyes large and elliptical; mandibles bidentate.

Mesosoma . Pronotum weakly convex, not depressed near posterior angles, anterior angles not produced, rugosely punctate; mesoscutellum weakly convex, weakly narrowed posteriorly, rugosely punctate; propodeum weakly convex, not laterally depressed, punctate posteriorly, not densely setose, rugosely punctate dorsally, impunctate laterally, closely and finely punctate posteriorly.

Metasoma. T1–5 and S1–5 closely and deeply punctate; T1 truncate, anterior angles rounded; T5 and S5 not produced; pygidium subtriangular, not spinose, closely punctate, anterolaterally subtuberculate.

Colour. Brown with indistinct yellowish-orange frontal maculae about eye size mesad to eye ventrally.

Length. Body 11–12 mm.

Distribution. South-western Western Australia near Noongar and McDermid Rock.

Etymology. The specific name is derived from Latin and refers to the colour of the female.

Remarks. Males resemble R. fulvescens sp. nov., which has the lower lobe of cuspis longer and projecting beyond the apex of upper lobe and is about three times longer than the lower lobe. They also resemble R. confusus and R. schichai which have the cuspis truncate in profile.

Differs from Rh. corrugatus by: punctation closer and deeper, rugose on head, mesosoma and S1; clypeus convex with an inverted Y-shaped carina; frons sagittally carinate to mid ocellus; pronotum with anterior margin acutely produced laterally; metanotum below level of mesoscutellum; propodeum oblique posteriorly; S2 anteromedially subtuberculate; S8 with angulate basal angles; cuspis bifid.

Females are unique in colouration among the known species. They resemble R. burnsi which has the head and body black and the legs ferruginous and R. fulvescens sp. nov. which is black and has T3-6 densely covered in fulvous setae.

Differs from Rh. corrugatus by: head subrectangular; frons longitudinally rugosely punctate, obscurely sagittally sulcate; vertex longitudinally rugose; gena closely punctate; pronotum, mesoscutellum and propodeum (dorsally) rugose; T1–5 and S1–5 closely and deeply punctate; pygidium subtriangular, not spinose, closely punctate; brown with obscure frontal maculae.

Material examined. Western Australia: holotype ♂ 5.5–6.5 km SW of McDermid Rock, 32o01'S, 120o44'E, 27.ix.–3.x.1978, T.F. Houston et al., ( WAM); paratypes: 1♀, mounted with holotype, ( WAM); 1♂, 1♀, 2 km SW by W of Noongar, 31o21'S, 118o57'E, 9.x.1981, I.D. Naumann and J.C. Cardale, ( ANIC).

Figures

FIGURE 17. Distribution of Rugosothynnus spp.: R. brunneus sp. nov., closed circles; R. burnsi, squares: R. clypeatus sp. nov., triangle; R. confusus sp. nov., open circles.

FIGURES 11 – 13. Rugosothynnus brunneus sp. nov. 11. genitalia, male, right lateral view; 12. genitalia, male, dorsal view; 13. pygidium, female, dorsal view. Scale lines = 0.5 mm.