Arpactophilus drehu, Breitkreuz, Laura C. V., Ohl, Michael & Engel, Michael S., 2016

Breitkreuz, Laura C. V., Ohl, Michael & Engel, Michael S., 2016, A review of the New Caledonian Arpactophilus (Hymenoptera: Crabronidae), Zootaxa 4063 (1), pp. 1-66 : 18-22

Arpactophilus drehu sp. nov.

( Figs. 47–48 )

Diagnosis. Arpactophilus drehu is the only New Caledonian species in the genus with the combination of one submarginal cell in the forewing and a fully yellow clypeus ( Fig. 47 ). Another distinctive feature is the presence of prominent silvery setae on the frons.

Description. FEMALE: Total length 3.2–4.1 mm, mean = 3.6 mm; forewing length 1.8–2.2 mm, mean = 2.1 mm.

Body black, with areas of brown and light yellow. Light yellow: clypeus; labrum; mandible; area around mandibular base ( Fig. 47 ); front of scape; anterior pronotal margin; pronotal lobe; tegula; coxae apically; pro- and mesofemora, apical half of metafemur; tibiae; tarsi. Brown: posterior of scape; pedicel; flagellum; coxae basally; basal half of metafemur. Wings hyaline; pterostigma light brown.

Head about 1.1 × as long as wide in frontal view. Apical margin of clypeus medially projecting, with shallow, broad concave incision ( Fig. 47 ). Apical margin of labrum with two lobes. Ventral mandibular tooth about ¼–1/5 of total mandibular length, not reaching opposite mandibular base. Palpal formula 4:3. Frons colliculate with dense punctation and dense silvery setae. Frontal carina present from median ocellus to apical margin of clypeus, forming a small point at basal clypeal margin. Scape 3.0 × as long as wide. Ocellar triangle anterior of tangent between upper posterior orbits of compound eyes, lateral ocelli anterior of tangent by approximately their diameter. Occipital carina continuous ( Fig. 5 ). Gena imbricate with long setae (ventrally denser than laterally), without tubercles, spines, or dorsoventral carina. Hypostomal midventral line carinate, not angulate.

Mesosoma about 1.9 × as long as wide in dorsal view. Propodeum about 0.9 × as long as wide in dorsal view. Mesosoma imbricate with dense punctation ( Fig. 48 ); lateral surface of propodeum also transversely carinulate; dorsal surface of propodeum also finely reticulate basally and transversely carinate apically (similar to pattern in Fig. 21 ). Pitted sulcus present posterior to fine mesoscuto-mesoscutellar sulcus. Hypersternal sulcus short, only as a slightly pitted area close to omaulus. Metafemur 2.7 × as long as wide. Metatibia without differently colored area apically. Pretarsal claws without teeth. Forewing with one submarginal cell. Hind wing with five distal hamuli.

Metasoma polished, sparsely punctate ( Fig. 48 ). Metasomal sternum II without bulge (as in Fig. 1 ). Pygidium with broad row of silk setae apically.

MALE: Unknown.

Remarks. Arpactophilus drehu is similar to A. drubea in size and coloration among the group of species with one submarginal cell. They can be distinguished most easily by the extent of the occipital carina, which is not continuous in the latter species. They also differ in the fully yellow clypeus of A. drehu , whereas only the apical half is yellow in A. drubea . The only other species with one submarginal cell in the forewing and that has a continuous occipital carina is A. dolichocara , but it is easily separated by differences in coloration, especially of the frons and clypeus (which is black or dark brown in A. dolichocara ).

Material examined. HOLOTYPE ♀: “Nouvelle Calédonie, Pindaï 30m, 18.IV.1995, Réc. Chazeau & Jourdan” [ MNHN].

PARATYPES 9♀: (8x) “Nouvelle Calédonie, Pindaï 30m, 18.IV.1995, Réc. Chazeau & Jourdan” [ CAS, MNHN, ZMB]; (1x) “Nouvelle Calédonie, Mont Koghis. 350m, 25.IV.1995, Réc. Chazeau & Jourdan” [ MNHN].

Etymology. The specific epithet is taken from the name Drehu , one of the New Caledonian native languages. It is treated as a noun in apposition.

Figures

FIGURES 47 – 52. Facial views and lateral habitus of ♀ holotypes of species of Arpactophilus Smith. 47. Arpactophilus drehu sp. nov., facial view; 48. A. drehu, lateral habitus; 49. A. drubea sp. nov., facial view; 50. A. drubea, lateral habitus; 51. A. fagauvea sp. nov., facial view; 52. A. fagauvea, lateral habitus.

FIGURES 5 – 9. Head and metatibial details of New Caledonian Arpactophilus Smith. 5. Schematic view of posterior of head of Arpactophilus, arrow indicates complete occipital carina; 6. Schematic with arrow indicating incomplete, dorsallyinterrupted occipital carina; 7: Metatibia of holotype ♀ of A. xaragure sp. nov., arrow indicating slightly differently colored but not differently-structured area apically; 8. Metatibia of holotype ♀ of Arpactophilus orowe sp. nov., arrow indicating differently colored and structured area apically; 9. Metatibia of paratype ♀ of A. orowe, scanning electron micrograph with arrow indicating concave area apically.

FIGURES 16 – 22., Dorsal surfaces of ♀ of species of Arpactophilus Smith. 16. Arpactophilus concavus Bohart; 17. A. irwini Bohart; 18. A. kumak sp. nov. (holotype); 19. A. merle sp. nov. (holotype); 20. A. caac sp. nov. (holotype); 21. A. kraussi Bohart; 22. A. propodealis Bohart.

FIGURES 1 – 4. Line drawings of metasomata and forewings of New Caledonian species of Arpactophilus Smith. 1. Metasoma in profile of ♀ of Arpactophilus merle sp. nov., arrow indicates unmodified metasomal sternum II; 2. Metasoma in profile of ♀ of A. irwini Bohart, arrow indicates ventrally swollen metasomal sternum II. 3. Forewing of ♀ of A. irwini; ps: pterostigma, sz I: submarginal cell I, sz II: submarginal cell II. 4, Forewing of ♀ of A. caledonicus Bohart; ps: pterostigma, sz I: submarginal cell I.