Dissomphalus decussatus Alencar & Azevedo, 2006

Alencar, I. D. C. C. & Azevedo, C. O., 2006, Definition of the coronatus species-group (Hymenoptera: Bethylidae, Dissomphalus) with description of thirteen new species, Zootaxa 1330, pp. 1-26 : 13-14

Dissomphalus decussatus Alencar & Azevedo , New Species

( Figs. 15–17 )

Diagnosis: paramere with concavity in apical margin with one median small tooth medially, dorsal protuberance large and rounded, ventral one with two teeth fused, dorsal margin with base developed and angled ventrally. Aedeagus with dorsal body narrowing to apex with concavity mesad, ventral margin straight, dorsal margin convex with subapical concavity; crown-process small.

Description: male, body length 2.4mm; LFW 1.9mm. Color: head and mesosoma black; metasoma castaneous; clypeus and mandible dark castaneous; antenna light castaneous and gradually darker in distal part; palpi and legs light castaneous except coxae and femora castaneous; wings subhyaline.

Head: mandible tridentate, uppermost tooth inconspicuous. Clypeus with trapezoidal median lobe, median carina complete. First four antennal segments in ratio of ~11:5:5:4, segment XI 2.3x as long as wide. Frons coriaceous and shiny with shallow and small punctures, separated by 1.0–1.5x their diameter. LH 1.0x WH; WF 0.6x WH; WF 1.1x HE; OOL 1.2x WOT; DAO 0.5x WOT; posterior ocelli distant from crest of vertex 0.5x DAO. Vertex concave with angulate corners. VOL 0.9x HE.

Mesosoma: thoracic dorsum weakly coriaceous, punctures small and shallow as on frons. Pronotal disc 0.4x length of mesoscutum, anterior margin carinate. Notaulus complete. Propodeal disc 1.3x as long as wide, irregularly rugose, median carina incomplete, posterior region polished and shiny; lateral surface of propodeum with irregular striae; declivity areolate-rugulose. Fore femur 2.4x as long as wide.

Metasoma: tergum II with pair of circular, inclined and deep lateral depressions, separated by 0.5x their diameter, each depression with tuft of convergent setae directed backward, antero-lateral margin with long setae. Hypopygium with posterior margin straight.

Genitalia ( Figs. 15–17 ): paramere with concavity in apical margin with one median small tooth medially, dorsal protuberance large and rounded, ventral one with two teeth fused ( Fig. 15 ), apex inclined with distinct long seta, dorsal margin with base developed and angled ventrally, ventral margin concave. Basiparamere rounded in ventral view. Cuspis long and arched with rounded apex, digitus acutely pointed, apical margin arched and serrate, basal margin straight, base with short setae and protuberance with rounded apex. Aedeagus with ventral ramus shorter than dorsal body, laminar, surface horizontal and angulate ventrally, basal half wide, apical half narrowing to apex and converging mesad of genitalia, apex somewhat expanded and directed dorsally; dorsal body wide, surface vertical, apex narrow with concavity mesad, ventral margin straight, dorsal margin convex with subapical concavity; crown-process small. Apodeme of aedeagus not extending beyond subcircular genital ring.

Material examined: HOLOTYPE: male, ECUADOR, Sucumbios, Sacha Lodge, 290m, 0.5ºS 76.5W [0°30’S 76º30’W], 13–23.IV.1994, Malaise trap, P. Hibbs col. ( LACM).

Comments: this species is very similar to D. coronatus in having aedeagus with ventral ramus with apical half narrow converging medially, dorsal body wide narrowing to apex, apex with concavity medially and crown-process small. However, D. decussatus has a unique modification of the paramere that is not present in D. coronatus : the concavity in the apical margin with one median small tooth medially.

Etymology: the specific epithet comes from Latin and refers to the ventral ramus of the aedeagus which is cruciform on holotype.

Distribution: Ecuador.

Figures

FIGURES 12 – 23. 12 – 14, Dissomphalus declinatus sp. nov. 12, metasoma, dorsal view; 13, genitalia, ventral view; 14, genitalia, dorsal view; 15 – 17, Dissomphalus decussatus sp. nov. 15, paramere, lateral view; 16, genitalia, ventral view; 17, genitalia, dorsal view; 18 – 19, Dissomphalus flexuosus 18, genitalia, ventral view; 19, genitalia, dorsal view; 20 – 21, Dissomphalus galeatus sp. nov. 20, genitalia, ventral view; 21, genitalia, dorsal view; 22 – 23, Dissomphalus hirtus sp. nov. 22, genitalia, ventral view; 23, genitalia, dorsal view. (Scale bars = 250 μm).