Dendrocerus africanus ( Risbec, 1958 )

Salden, Tobias & Peters, Ralph S., 2023, Afrotropical Ceraphronoidea (Insecta: Hymenoptera) put back on the map with the description of 88 new species, European Journal of Taxonomy 884 (1), pp. 1-386 : 364-367

Dendrocerus africanus ( Risbec, 1958)

Fig. 104

Johnson & Musetti 2004: 86.

Dendrocerus africanus – Mikó 2012e, 2012f, 2012g (male genitalia external and internal and ventral and dorsal view).

Diagnosis

Proximal quarter of metatibia transparent; flagellomeres cylindric and F1 to F6 branched; scape longer than F1 to F3 combined; head width 1.92 × interorbital space; OOL 1.78 × lateral ocellus size; OOL:LOL 1.23; mesoscutum width 1.75 × mesoscutellum width; mesoscutellum length 1.02 × mesoscutellum width. Male genitalia: harpe finger-shaped in ventral and dorsal view; harpe/gvc index 0.25; dorsomedial margins of harpes not touching at distodorsal margin of gvc, dorsomedial margin of harpe convex and distolaterally oriented with small protrusions in approximately basal quarter, slightly concave and converging distomedially in approximately apical three quarters; volsella with four distal setae, oriented distomedially and distoventrally; distolateral margin of gvc strongly descending in ventral quarter; genital length 2.12 × gvc width.

Material examined

KENYA • 1 ♂; Western Province, Kakamega Forest; 00°21′7.9 N, 34°52′2.6 E; 1597 m a.s.l.; 2 Jul. 2007; F. Hita Garcia leg.; Transect 7; primary rain forest; Winkler leaf litter extraction; ZFMK; ZFMK- HYM-00037005 .

Description (based on ZFMK-HYM-00037005)

Male

BODY LENGTH. 2.44 mm.

COLOUR. Head black, mesosoma black, metasoma dark brown; scape and pedicel light brown, flagellum dark brown; fore and middle leg yellowish except pro- and mesocoxa dark brown, hind leg brown except metacoxa black and proximal quarter of metatibia transparent; fore wing venation brown, fore and hind wing disc slightly melanized.

ANTENNA. 11-segmented, flagellomeres cylindric and F1 to F6 branched; scape 4.7 × as long as pedicel, scape longer than F1 to F3 combined, F1 0.2 × as long as F1 branch, F1 1.2× as long as pedicel, F1 branch 0.7× as long as F2 branch, F2 branch 0.9 × as long as F3 branch, F1 shorter than F7 and F8 combined, F1 shorter than F9, F6 0.6× as long as F6 branch, F6 4.6 × as long as wide, F6 shorter than F7 and F8 combined, F6 0.7 × as high as F9; numerous distinctly small multiporous plates on flagellomeres, sensillae on flagellomeres erect and longer than width of F1 to F7.

HEAD. Head width 1.33 × head height; head width 1.92 × interorbital space; maximum eye diameter 1.14 × minimum eye diameter; head height 1.80 × maximum eye diameter. Dorsal margin of occipital carina ventral to dorsal margin of lateral ocellus in lateral view; preoccipital furrow indistinct; preoccipital carina distinct. OOL:POL:LOL 1.00:1.86:0.81; OOL 1.78 × lateral ocellus size. White, thick setae on upper face absent; supraclypeal depression present; lateral margin of torulus slightly raised; intertorular carina present; posterolateral processes of gena absent.

MESOSOMA, METASOMA. Mesosoma not compressed laterally. Head width 1.03 × mesosoma width; Weber length 950 µm. Mesoscutum densely setose, setae curved backwards; notaulus present; median mesoscutal sulcus present; median mesoscutal sulcus adjacent to transscutal articulation; interaxillar sulcus absent (= scutoscutellar sulcus adjacent to transscutal articulation), scutoscutellar sulcus slightly concave; dorsal axillar area densely setose, setae curved backwards; mesoscutellum densely setose, setae curved backwards or straight. Mesoscutum width 1.75 × mesoscutellum width; posterior mesoscutal width 1.20 × mesoscutellum width; mesoscutellum length 1.02 × mesoscutellum width; mesoscutellum length 0.85× posterior mesoscutal width; Weber length 1.09 × mesoscutum width; Weber length 1.86 × mesoscutellum length. Anteromedian projection of the metanoto-propodeo-metapecto-mesopectal complex straight and oriented posterodorsally in lateral view with pointed and bifurcated end, extending to end of mesosoma; mesometapleural sulcus present; posterior propodeal projection conspicuously short in ventrolateral view; posterior mesosomal comb absent. At least ten distinct, basal longitudinal carinae on syntergum; pairs of translucent patches on metasomal syntergum and synsternum.

FORE WING. Length 2.31 × width; stigmal vein slightly longer than pterostigma marginal length; pterostigma present.

MALE GENITALIA. Genital length 344 µm; Weber length 2.76 × genital length; gvc width 163 µm; genital length 2.12× gvc width; gvc width more than half of gvc length; gvc width 1.31 × distal gvc width. Proximodorsal margin of gvc straight; distodorsal margin of gvc strongly descending proximomedially in median part, lateral part convex ( Fig. 104C ); proximoventral margin of gvc concave; distoventral margin of gvc strongly descending proximally and at lateral volsella margin strongly ascending distomedially ( Fig. 104A ); ventral area of gvc convex; dorsal area of gvc slightly convex ( Fig. 104B ); proximolateral margin of gvc strongly ascending ventrally; distolateral margin of gvc strongly descending in ventral quarter ( Fig. 104B ). Harpe finger-shaped in ventral and dorsal view; harpe/gvc index 0.25; lateral articulation site of harpe with gvc not flush ( Fig. 104A, C ); ventral margin of harpe straight and slightly curved distodorsally at its middle, dorsal margin concave with distinct setae-bearing protrusions ( Fig. 104B ), lateral margin slightly convex, widest point of harpe at lateral articulation site with gvc ( Fig. 104A, C ); dorsomedial margins of harpes not touching at distodorsal margin of gvc, dorsomedial margin of harpe convex and distolaterally oriented with small protrusions in approximately basal quarter, slightly concave and converging distomedially in approximately apical three quarters ( Fig. 104C ), apex of harpe pointed, oriented distomedially ( Fig. 104A, C ). Harpe with at least eight lateral setae, longest lateral setae more than half as long as harpe, lateral setae oriented distolaterally, distoventrally and medioventrally; harpe with at least two apical setae, longest apical setae two thirds as long as harpe, apical setae distinctly crossing and oriented distomedially and distoventrally; harpe with at least seven median setae, longest median setae half as long as harpe, median setae distinctly crossing and oriented distomedially, distoventrally and medioventrally; volsella with four distal setae, oriented distomedially and distoventrally ( Fig. 104A ). Aedeagus + gonossiculus more than two thirds as long as harpe, apex of aedeagus + gonossiculus rounded ( Fig. 104A, C ) and dorsal to apex of harpe. Genitalia strongly sclerotized with strongest sclerotization at distal volsella and aedeagus + gonossiculus and weakest sclerotization at apical half of harpe and basal part of aedeagus + gonossiculus.

Female

See measurements of apallotype by Dessart (1999: 198) [type terminology taken from Dessart (1999)].

Variation

The male genitalia of the specimen (7209/291), which is illustrated by Dessart (1999: 199, fig. 48), show asymmetrical setae at the volsella (three on the right and four on the left side; ZFMK-HYM-00037005 has four setae on both sides).

Biology

Host unknown, ZFMK-HYM-00037005 collected from leaf litter.

Distribution

Afrotropical: Democratic Republic of the Congo, Ivory Coast, Kenya and Uganda.

Type depository

The male holotype, and at least three male specimens and one female apallotype are deposited in the RMCA. For more details see Dessart (1999: 200).

Remarks

Male and male genitalia known. The specimen ZFMK-HYM-00037005 is recognised as Dendrocerus africanus ( Risbec, 1958) , based on the distinct character combination described and illustrated by Risbec (1958), Dessart (1962) and Dessart (1999). The most obvious character is the sixfoldedly branched antenna. However, Dessart (1999) already mentioned intraspecific variability in the number of branches of the antenna. Thus, this character alone might not be sufficient for species delimitation. Dessart (1999) also described the bifurcated shape of the anteromedian projection of the metanoto-propodeo-metapecto-mesopectal complex and the colouration of the hind leg, and added a detailed drawing of the male genitalia. In addition, Mikó (2012e, 2012f, 2012g) provided CLSM volume rendered media files of the male genitalia. All examined body and male genitalia characters of D. africanus match with ZFMK- HYM-00037005.

The posterior part of the metasoma of ZFMK-HYM-00037005 is detached, thus the body length measurement is not precise.

Figures

Fig. 104. Specimen of Dendrocerus africanus (Risbec, 1958) (ZFMK-HYM-00037005). A–C. Male genitalia in ventral (A), lateral (B) and dorsal (C) views. D. Habitus in lateral view; inset: antennae.