Ophrynopus rufocephalus Vilhelmsen, 2020

Vilhelmsen, Lars, 2020, Two new species of Ophrynopus Konow, 1897 (Hymenoptera: Orussidae), with a new definition of the genus, Zootaxa 4790 (1), pp. 121-137 : 127-130

Ophrynopus rufocephalus Vilhelmsen , new species

Figs 4 , 5

http://zoobank.org/:act: 85C69724-794B-4033-B16E-5C1BC1526473

Material. ECUADOR: Holotype, female, ” Ecuador , Morona-/ Santiago , Cord. de/ Cutucu 6K e. of Macas / 1,100m / 12. v.1981 / M. Cooper ”. ( NHML)

Description, female. Body length 7.9 mm, fore wing length 5.1 mm. Strikingly bicolored ( Fig. 4A ), head and prothorax predominantly reddish brown, except for black coronal teeth and mandibles ( Fig. 4B ); remainder of body predominantly dark brown to black, except for mid and hind coxae and femora, and tergum 10 and cercus, which are reddish brown. Fore wing with pterostigma and venation mostly dark brown, except within hyaline areas ( Fig. 5B ); two large infuscate areas with dense setation present, basal area extends from wing base to just proximally of pterostigma, distal area separated from proximal by hyaline band, extends across wing from just proximal to vein 2r-rs to some distance from tip, leaving tip of wing hyaline, boundary between distal infuscate area and hyaline tip wavy; hind wing vein R dark brown, venation otherwise light brown, some longitudinal veins darker in the basal part, single weakly infuscate area extends from R–Rs fork to tip of wing.

Head. Ocellar corona narrow, distance between median ocellus and lateral coronal teeth approximately equal to width of ocellus; dorsalmost coronal teeth situated dorsal to lateral ocelli, small and staggered in regular pattern several teeth wide ( Figs 4B , 5A ), medially separated by narrow longitudinal groove. Dorsal transverse, median and lateral frontal carinae absent. Setae on frons not conspicuously flattened. Ventral transverse frontal carina with very prominent median notch ( Fig. 4B ); median longitudinal line extends from notch to ocellar corona, flanked by two diverging sublateral lines that do not extend as far dorsal as median one, all lines faint. Postocular carina absent, occipital carina well developed ( Fig. 5A ), occipital concavity absent; setation on gena weakly developed except ventrally lateral to carina laterally delimiting the subantennal groove. Frons, vertex, and gena areolate. Antenna slender, antennomere 9 not swollen subapically, antennomere 10 approximately 3× as long as wide ( Fig. 4C ).

Thorax. Pronotum with very distinct transverse carina anterodorsally, carina projecting anteriorly and with prominent notch medially ( Figs 4A , 5A ); pronotum not longer laterally than medially in dorsal view, areolate dorsally, smooth with scattered punctures on anterior face. Fore femur with distinct carina ventrally. Mesoscutum only slightly shorter than broad, areolate, longitudinal carina absent, pilosity indistinct ( Fig. 5A ); mesoscuto-scutellar sulcus distinct, with deep rectangular pits, axillar flanges distinctly carinate, rectangular; mesoscutellum areolate, with indistinct lateral margins, posteriorly parallel with anterior margin of metanotum for some distance. Mesopleuron with distinct mesepisternal carina, areolate dorsally except for small glabrous/imbricate depression with few large pits posterodorsally, finely punctate ventrally, with silvery pilosity only ventrally. Metanotum areolate with median and lateral longitudinal carinae not discernible. Metepisternum areolate except for small glabrous area in middle. Hind coxa laterally striate, without pilosity; hind femur with small denticles ventrally, but no carina; hind tibia dorsally with pegs in two rows ( Fig. 5C ), outer row with eleven pegs, and with longitudinal carina laterally; apical hind tibial spurs of approximately equal length, short, less than half apical tibial width. Fore wing with vein cu-a inserting on Cu approximately 1/3 from proximal end of cell M ( Fig. 5B ).

Abdomen. Pilosity indistinct. Tergum 1 areolate, with distinct postspiracular and subspiracular carina laterally, area below subspiracular carina glabrous. Terga 2-8 finely areolate to punctate, longitudinal carina on tergum 2 absent, smooth areas laterally on tergum 2 minute, hardly discernible ( Fig. 5C ). Tergum 9 finely areolate punctate anteriorly, coarsely areolate posteriorly, with distinct longitudinal carinae submedially; carinae short triangles with several spines aligned with them anteriorly. Abdominal sterna finely areolate punctate.

Male. Unknown.

Etymology. The species epithet, a noun, literally translates as ‘redhead’, which is highly appropriate ( Figs 4A,B , 5A ).

Comments. Ophrynopus rufocephalus has a unique color pattern; a reddish brown head has not previously been observed in any Orussidae described so far. The new species closely resembles Ophrynopus seagi in a number of traits: the presence of a median notch on the ventral transverse frontal carina, the absence of a postocular carina, female antennomere 9 not swollen apically and without carina, the presence of a strongly developed transverse pronotal carina with a median incurvation, and the presence of a distinct medioventral groove on abdominal tergum 9. Apart from the color scheme, it can be separated from O. seagi by the configuration of the dorsal ocellar teeth in a staggered, regular pattern (in low transverse rows in O. seagi ), the presence of a ventral longitudinal carina on the fore femur (absent in O. seagi ), having the mesoscutellum less well defined laterally (with a glabrous strip laterally in O. seagi ), and having the smooth areas laterally on abdominal tergum 2 hardly developed (distinct in O. seagi ).

The three faint longitudinal lines observed on the frons on O. rufocephalus ( Fig. 4B ) probably indicates internal septa, which are observed in a number of Orussidae both extant and extinct ( Vilhelmsen & Zimmermann 2014). The septa serve as attachment areas for the highly developed extrinsic labral musculature in Orussidae ( Vilhelmsen 1996) and are probably a ground plan feature of the family. The septa are probably easier to observe externally in O. rufocephalus because of its lighter head capsule coloration; in other more darkly colored specimens, it is not possible to see the trace of the septa through the head cuticle.

The type locality is also the place of the only previously published record of Orussidae from Ecuador ( Vilhelmsen & Smith 2002); this is a female of Ophrynopus nigricans , collected October 26 th 1978 by M. Cooper. In the Appendix, additional records from Ecuador of O. fulvostigma are listed.

Figures

FIGURE 4. Ophrynopus rufocephalus n. sp., female holotype (NHML). A. Habitus, lateral. B. Head, anterior. C. Antenna. Green arrow = transverse pronotal carina; red arrow = longitudinal carina on abdominal tergum 9; yellow arrow = groove between dorsalmost coronal teeth; white arrows = longitudinal lines on frons; blue arrow = notch in ventral transverse frontal carina.

FIGURE 5. Ophrynopus rufocephalus n. sp., female holotype (NHML).A. Head and thorax, dorsal. B. Fore wing. C.Abdomen and hind leg, dorsal. Yellow arrow = groove between dorsalmost coronal teeth; blue arrow = occipital carina; green arrows = transverse pronotal carina; red arrow = vein cu-a; violet arrows = pegs on hind tibia.