Petersenidia modkhong Williams, 2019

Williams, Kevin A., Lelej, Arkady S., Okayasu, Juriya, Borkent, Christopher J., Malee, Rufeah, Thoawan, Kodeeyah & Thaochan, Narit, 2019, The female velvet ants (aka modkhong) of southern Thailand (Hymenoptera: Mutillidae), with a key to the genera of southeast Asia, Zootaxa 4602 (1), pp. 1-69 : 40

27a. Petersenidia modkhong Williams , sp. nov.

( Figs 24 , 141–142 )

Diagnosis. FEMALE. The following combination of characters is diagnostic: humeral angle sharply produced, pronotum broader than propodeum, mesosoma uniform orange, legs partly orange, metasoma entirely black, T2 sculpture coarse, T2 disc spots moderate and separated by approximate spot diameter, T2 with sparse pale golden apical fringe, T3 band entire, and pygidium smooth. Body length 6.4 mm. MALE. Unknown.

Description. FEMALE. Body length 6.4 mm. Coloration. Head black, except mandible base and scape orange, and clypeus, antennal tubercle, and base of flagellum largely orange-brown. Mesosoma, coxae, and femoral bases orange-brown, femoral apices, tibiae, and tarsi largely brown. Metasoma black, except T6 dark redbrown and S1 orange-brown. Body setae generally sparse and silvery, except frons and mesosomal dorsum with sub-erect golden and red-brown setae; T2 disc, T4, and T5 setae dense black; and vertex, T2 disc lateral spots, T3 entirely, and T6 basal tuft with dense pale golden setae; T2 lateral spot diameter subequal to distance between spots, T2 with sparse apical fringe of pale golden setae, and T3 band entire. Head. Width behind eye subequal to mesosoma width. Frons, vertex, and gena punctures coarse confluent. Mandible apex narrow bidentate. Clypeus apically weak bidentate, teeth connected by weak transverse carina; basomedial portion with robust tubercle. Antennal scrobe with nearly flat dorsal carina and straight lateral carina. Antennal tubercle with scattered micropunctures. Genal carina distinct, forming tooth at hypostomal carina and extending posteriorly to occipital carina. F1 3.0 × pedicel length, F2 1.9 × pedicel length. Mesosoma. Length subequal to width. Dorsum of mesosoma with coarse confluent punctures; wavy carina separating dorsal and lateral faces of pronotum and mesonotum. Side of mesosoma with dense micropunctures and short setae. Mesopleural lamella an obscure carina. Humeral carina distinct, anterolaterally expanded dorsally. Ratio of width of humeral angle, anterior spiracle, narrowest point of mesonotum, propodeal spiracle, and midpoint of propodeum 48:49:40:43:42. Scutellar scale truncate posteriorly, ~2 punctures wide, surrounded by scattered tubercles. Posterior propodeal face reticulate with many interspaces obliterated leaving apparent striae and tubercles. Lateral and posterior propodeal faces separated by row of teeth. Metatibio-tarsal ratio 54:23:15:12:9:9. Metasoma. T1 anterior face with separated punctures, posterior with confluent punctures. T2 disc with deep coarse dense ovate pits, interspaces micropunctate and setose; with transverse depression in apical half. T3–5 and S3–5 with small dense punctures. S1 with simple longitudinal lamella. S2 with coarse dense punctures, interspaces smooth. T2 felt line 0.3 × T2 total length. T6 with long sub-ovate pygidium, widest sub-apically with lateral carina obliterated in posterior half; smooth throughout. S6 posterior margin truncate.

Material examined. Holotype ♀, THAILAND, Trang, 18 km E Trang, Khao Chong N.P., 400 m, 7 o 34'N 99 o 49'E, 24.V.1988, R. Hensen (RMNH). Paratype (1 female), THAILAND, Songkhla, Ton Nga Chang National Park , 24.VII.1997, Sk. Yamane (1♀ SKYC) .

Distribution. Thailand (Songkhla, Trang).

Etymology. From the Thai “มดขนปก, modkhongpok ” or “มดขน, modkhong” for short, the local common name for Mutillidae .

Remarks. In Chen’s (1957) key, this species terminates at couplet 7 of the Smicromyrme key, because the pygidium is smooth and the S1 carina is entire. In Mickel’s (1935) key, it keys to Petersenidia psecas ( Mickel, 1935) , which is known only from Borneo.

Figures

FIGURES 1–28. Mutillidae, dorsal habitus of females. Scale bars represent actual specimen length.

FIGURES 137–146. Mutillinae: Trogaspidiini females III. 137–138. Orientidia manleyi, sp. nov.; 139–140. O. thoawanae, sp. nov.; 141–142. Petersenidia modkhong, sp. nov.; 143–144. Petersenidia leleji, sp. nov.; 145–146. Promecidia ninnii. 137, 139, 141, 143, 145. Habitus, dorsal view; 138, 140, 142, 144, 146. Habitus, lateral view.