Dissomphalus zethus Mugrabi & Azevedo

MUGRABI, DANIELE F. & AZEVEDO, CELSO O., 2013, Revision of Thai Dissomphalus Ashmead, 1893 (Hymenoptera, Bethylidae), with description of twenty four new species, Zootaxa 3662 (1), pp. 1-73 : 40

Dissomphalus zethus Mugrabi & Azevedo , sp. nov.

( Figs 54– 56 , 112, 186–187)

Description. MALE. Body length 2.24 mm. LFW 1.52 mm. Maximum wing width 0.65 mm. Color. Head and mesosoma black; metasoma dark castaneous.

Head. Mandible with apical tooth. Clypeus with median lobe subtrapezoidal; median tooth angulate or nearly so; median carina complete apically or nearly so. Ratio of first four antennal segments about 11:6:5:3. Frons strongly coriaceous, punctures small. LH 1.06 × WH, WF 0.68 × WH, WF 1.44 × HE, OOL 1.27 × WOT, DAO 0.36 × WOT, posterior ocelli distant from vertex crest 0.75 × DAO, frontal angle of ocellar triangle right, VOL 0.94 × HE. Vertex crest straight. Occipital carina not visible in dorsal view.

Mesosoma. Pronotal disc strongly coriaceous, anterior margin ecarinate. Notauli deep, complete, evenly narrow, converging posterad. Propodeal disc 0.56 × as long as wide; basal triangle rugulose, posterolateral area imbricate; median carina posteriorly incomplete; lateral margins strongly convex, parallel; posterior carina absent. Lateral of propodeum mostly strongly coriaceous. Propodeal declivity mostly imbricate.

Metasoma. Tergal process with very shallow, subcircular and sublateral pair of depressions; depressions 0.7 × as long as tergite II, diverging posterad, distant each other 1.14 × maximum transverse diameter, with setae short and lateroposterad on lateral area, without pair of tubercles, with laterad tuft of setae ( Figs 54– 56 ). Hypopygium with median stalk 1.23 × as long as hypopygeal plate; median stalk wide; corner of anterior margin angular; lateral stalk of hypopygium 0.14 × as long as median stalk; posterior margin weakly concave; corner rounded (Fig. 112).

Genitalia ( Figs 186–187 ). Genital ring produced, each half convex in dorsal view. Basiparamere with dorsal surface rectangular, much narrower than ventral surface. Paramere with basal area wider than basiparamere apex; apex subangulate; apical margin weakly concave in ventral view, not curved. Basivolsella glabrous. Aedeagus 2.16 × as long as wide; dorsal body of aedeagus wider medially, narrowing progressively apicad, lateral margin strongly convex medially, parallel, not curved dorsad, apex with one pair of outer lobe; base of dorsal body of aedeagus weakly sclerotized, triangular, with median region angulate; ventral ramus of aedeagus surpassing half length of dorsal body, not reaching base of apical lobe of dorsal body, lateral margin sinuous, much wider medially and base as narrow as apex. Apodeme extending beyond genital ring.

FEMALE. Unknown.

Material examined. Holotype, ♂. THAILAND. Loei: Phu Kradueng NP, Bamboo forest at Lam Huay Taad at Loei forest unit 2 (E-lerd), 16°56.565’N 101°48.896’E, 273 m, Malaise trap, 18–25.ix.2006, Sutin Glong-lasae leg., T951 . Paratypes: THAILAND. Malaise trap , Sakon Nakhon: 1 ♂ Phu Phan NP, Creek at northend of Huay Nam Pung Forest Unit, 16°55.789’N 103°54.158’E, 305 m, 25.xi–2.xii.2006, Winlon Khongnara leg., T1105 . Khonkaen: Nam Pong NP, office, 16°37.377’N 102°34.454’E, 344 m, 1 ♂ 5–12.vii.2006, Khamphol Jaidee leg., T106 , 1 ♂ 12–19.vii.2006, T110 . Chaiyaphum: 1 ♂ Tat Tone NP, Near stream, 15°58.771’N 102°2.397’E, 305 m, 12–19.vii.2006, T. Jaruphan & O. Budsawong leg., T221 . Ubon Ratchathani: 1 ♂ Pha Taem NP, Rong Hi Noy , 15°40.021’N 105°30.448’E, 240 m, 1–7.i.2007, Thongkam & Pakdee leg., T1476 .

Variations. Body length between 1.90 and 2.24 mm; LFW between 1.25 and 1.63 mm; maximum wing width between 0.57 and 0.64 mm; clypeal median tooth directed ventrad in lateral view; median carina of clypeus strongly arched in lateral view; transverse carina above antennal torulus present, 0.14 to 0.25 × as long as clypeal median lobe; notaulus posteriorly incomplete, 0.80 × as long as mesoscutum; median carina of propodeal disc absent, when present, varies between straight and sinuous; anterior surface of depression of tergal process with tuft of seta.

Remarks. D. zethus sp. nov. is similar to D. chiangmaiensis because of the following characteristics: hypopygium with median stalk wide and short, posterior margin straight with rounded corners, which are more projected than median region; base of paramere wider than basiparamere apex; aedeagal dorsal body bottle-shaped, wider medially, dorsal surface with conical median projection. However, D. zethus sp. nov. differs from D. chiangmaiensis as follows: hypopygium with lateral stalk wide and short, median stalk with apical constriction, lateral margin convex; base of paramere much wider than basiparamere apex; dorsal surface of basiparamere evenly narrow, genital ring with inclination angle between 45 and 90º; aedeagal dorsal body without warts at upper lateral surface, its inner lobe little exposed in dorsal view; aedeagal ventral ramus short and evenly wide.

Figures

FIGURES 54–68. Metasoma, 54– 56, Dissomphalus zethus sp. nov., 54, metasoma in dorsal view; 55, tergal process of metasoma in dorsal view; 56, tuft of setae of tergal process in dorsal view; 57–59, D. hetus sp. nov., 57, metasoma in dorsal view; 58, tergal process of metasoma in dorsal view; 59, tuft of setae of tergal process in dorsal view; 60–61, D. joelus sp. nov.,

FIGURES 186–193. Male genitalia, 186–187, Dissomphalus zethus sp. nov., 186, dorsal view; 187, ventral view; 188–191, D. hetus sp. nov., 188, dorsal view; 189, ventral view; 190, lateral view; 191, apex of aedeagus in ventral view; 192–193, D. joelus