Dissomphalus uncus Alencar & Azevedo, 2008

Alencar, I. D. C. C. & Azevedo, C. O., 2008, A new species-group of Dissomphalus (Hymenoptera: Bethylidae), with description of thirteen new species, Zootaxa 1851 (1), pp. 1-28 : 25-27

Dissomphalus uncus Alencar & Azevedo , sp. nov.

( Figs. 90–102 )

Diagnosis: male. This is the unique species of microstictus group which tergal process is considered a diagnostic feature. The second tergite of the metasoma presents a tergal process with a pair of dropped-shaped, large and deep lateral depression, each depression with minute tubercle with small pit on top. The following unique combination of genitalia characters are also needed to confirm the identity of the males of D. uncus : the paramere wide basally in dorsal view; the ventral ramus with inner margin straight except mid part of basal half concave, the filament inserted apically, nearly as long as ramus, sinuous; the dorsal body with basal bar triangular; the connector with diamond-shaped lateral expansion, mid part darker and dropped-shaped and the basal plate with upper margin concave, median lower margin straight.

Female. Females of Dissomphalus are hardly separable due the morphological similarity. The female of D. uncus can only be diagnosed by the following unique combination of characters: the head longer than wide, the mandible tetradentate with subupper tooth smaller than uppermost and it is hard to be observed; the clypeus with median lobe rounded, mid part elevate and thick in frontal view; the pronotal collar and neck almost at same level of pronotal disc when seen in lateral view, the mesoscutum depressed in middle in lateral view and the fore basitarsomere robust.

Description: male, body length 4.70 mm; LFW 3.45 mm. Color: head and mesosoma black; clypeus dark castaneous; metasoma castaneous; mandible, palpi and legs yellowish; antenna castaneous and gradually darker distally; wings subhyaline.

Head: mandible bidentate. Clypeus with trapezoidal median lobe, median carina complete, tall in lateral view. Relative length of first four antennal segments ~8:4:3:4 segment XI 2.0x as long as wide. Frons strongly coriaceous, punctures small and shallow, separated by 1.0–2.0x their diameter. LH 1.0x WH; WF 0.6x WH; WF 1.3x HE; OOL 0.8x WOT; DAO 0.4x WOT; posterior ocellus distant from crest of vertex 1.5x DAO. Vertex somewhat concave; VOL 0.8x HE.

Mesosoma: thoracic dorsum weakly coriaceous, except pronotal disc strongly coriaceous, punctures smaller and sparser than those of frons. Pronotal disc 0.5x length of mesoscutum. Notaulus complete. Propodeal disc 0.7x as long as wide, irregularly rugose, median carina incomplete, posterior part elevate, polished and shinny, lateral corner weakly coriaceous and areolate; lateral surface of propodeum imbricate; declivity imbricate, median carina complete. Fore femur 3.1x as long as wide.

Metasoma ( Fig. 90 ): tergite II with pair of dropped-shaped, large and deep lateral depression, separated by 2.5x its maximum diameter, each depression with minute tubercle which has small pit on top, anterior inner margin with very short few setae and lateral margin with short setae. Hypopygium with posterior margin concave.

Genitalia ( Figs. 91–95 ): paramere wide basally in dorsal view; apex rounded and arched mesad; ventral margin strongly concave apically, apical corner large and rounded, somewhat concave basally; dorsal margin somewhat convex with subapical acute concavity ( Figs. 91, 92, 95 ). Dorsal margin of basiparamere sinuous. Cuspis long and arched, apex rounded, digitus with apex pointed and smooth in upper margin. Aedeagus with ventral ramus shorter than dorsal body, laminar, surface horizontal, completely flat, inner margin straight except mid part of basal half concave, base with narrow fold, outer margin convex, filament inserted apically, nearly as long as ramus, sinuous, narrow except medially somewhat dilated, thin and arched dorsad ( Fig. 91 ); dorsal body with two pairs of apical lobes, outer pair laminar, surface vertical, wide narrowing to apex, apex straight, dorsal margin convex in lateral view ( Fig. 94 ) and with two concavities in dorsal view ( Fig. 92 ), ventral margin with subapical strong concavity, projection concave with apical corner dilated ( Figs. 93, 94 ), inner pair membranous, and hairy; basal bar triangular, upper margin concave, lateral margin folded mesad, lower margin touching basal plate; connector with diamond-shaped lateral expansion, with mid part darker and dropped-shaped; basal plate with upper margin concave, median lower margin straight ( Fig. 92 ). Apodeme of aedeagus extending beyond elliptical genital ring.

Description. female (in copula). Body length 2.10 mm ( Fig. 96 ). Color: yellowish.

Head: mandible tetradentate, two uppermost teeth inconspicuous, subupper tooth smaller than uppermost, lower teeth well defined, large and sharpened (98). Clypeus with rounded median lobe and median carina strong in dorsal view, mid part elevate and thick in frontal view ( Fig. 99 ). Eye small and elliptical, with four irregular facets surrounded by dark margin, distant of mandible 1.5x its length ( Fig. 97 ). Relative length of first four antennal segments ~11:5:2:2, segment XI 0.6x as long as wide. Scape long, pedicel funnel-shaped, flagellomeres getting large except last one longer than others, pointed and apex rounded. Frons coriaceous, punctures shallow, separated by 1.0–1.2x their diameter. Head longer than large, sides converging to vertex, hairs convergent. LH 1.5x WH, head with sides parallel, convergent posteriorly. Gena 0.5x LH. Temple short.

Mesosoma: thoracic dorsum coriaceous with punctures smaller and sparser than on frons, hairs long and sparse. Collar and neck pronotal almost at same plane of pronotal disc. Pronotal disc 3.7x length of mesoscutum, 1.3x as long as wide, posterior margin somewhat concave in posterior view. Mesoscutum depressed in middle in lateral view ( Fig. 100 ), 0.3x length of pronotal disc, posterior margin convex in posterior view. Propodeum coriaceous, propodeal disc with maximum width 1.1x minimum width. Pleurosternum with posterior margin produced. Metasternum diamond-shaped. Legs weakly coriaceous. Fore femur 2.4x as long as wide; fore basitarsomere robust ( Fig. 101 ), longer and larger than others tarsomeres ( Fig. 102 ). Fore, median and posterior tibia developed, hairy and with spurs.

Metasoma: petiole coriaceous and with striae strong, 0.1x length of metassoma ( Fig. 100 ). Metasoma polished and shinny. Transversal section elliptical.

Material examined: HOLOTYPE: male, VENEZUELA, Aragua, Rancho Grande , 1370 m, [~ 10º12’N 63º29’W], 25–28.ii.1995, FIT, R. W. Brooks col. ( CNCI) . ALLOTYPE: female, in copula, VENEZUELA, Aragua, Rancho Grande , 1450 m, 1–8.iii.1995, [~ 10º12’N 63º29’W], FIT, R. W. Brooks col. ( CNCI) . PARATYPES: VENEZUELA, Aragua, Rancho Grande , 1370 m, [~ 10º12’N 63º29’W], FIT, R. W. Brooks col. ( CNCI): 3 males, 1–8.iii.1995 ; 1 male (in copula), 1450 m, 1–8.iii.1995.

Variation: body length of male from 3.45 to 5.2 mm; clypeus subtrapezoidal, tergal process with depression and tubercle larger or smaller than holotype.

Comments: the male genitalia of D. uncus are similar to those of D. perventriosus by having the filament of ventral ramus inserted apically and the outer lobe of the dorsal body with the dorsal margin with two concavities in dorsal view. However D. perventriosus has the dorsal margin of the paramere very wide basally in dorsal view and the filament of the ventral ramus convergent, whereas D. uncus has the dorsal margin of the paramere much less wide basally in dorsal view and the filament of the ventral ramus sinuous.

Etymology: the specific Latin epithet refers to the ventral margin of the outer lobe of the dorsal body, which resembles a hook.

Distribution: Venezuela.

Figures

FIGURES 90–102. Dissomphalus uncus. 90–95, male; 90, tergal process, dorsal view; 91, genitalia, ventral view; 92, genitalia, dorsal view; 93, outer lobe, ventral view; 94, apex of dorsal body, lateral view; 95, paramere, lateral view; 96– 102, female; 96, body, dorsal view; 97, head, lateral view; 98, mandible, frontal view; 99, clypeus, frontal view; 100, mesosoma profile, lateral view; 101, fore leg, lateral view; 102, middle leg, lateral view. (Scale bars = 250 µm).