Chelonus (Microchelonus) matilei Braet et Rousse

Braet, Yves, Rousse, Pascal & Sharkey, Michael, 2012, New data on African Cheloninae (Hymenoptera, Braconidae) show a strong biogeographic signal for taxa with spined propodea, Zootaxa 3385, pp. 1-32 : 11-14

Chelonus (Microchelonus) matilei Braet et Rousse , sp. nov.

( Figs 30–36 )

FEMALE (Holotype). Body length 2.6 mm, forewing length 2.5 mm.

Head ( Figs 31, 36 ). Head 0.76x as length as height (in lateral view). Antennal socket inserted near middle level of eye, not acute. Antenna with 14 flagellomeres. Scapus 2.40x as long as wide, equal to first flagellomere, without apical lobe. First flagellomere 6x as long as wide, equal to second (five first flagellomeres almost equal in length). Penultimate flagellomere 2x as long as wide, 0.50x as long as first segment, shorter than apical segment. Eye length 3x length of temple (in dorsal view), 1.90x as high as broad, with dense, short setae. Maxillary palpus of normal length (ending between fore and middle coxa). Clypeus flattened in lateral view, with slightly convex lower margin, without apical teeth, weakly punctate. Malar suture absent but presence of several fine rugae running from base of eye to base of mandible. Malar space 1.50x basal width of mandible, 0.43x eye height. Face straight in lateral view, punctate (but presence of weak longitudinal striae between base of eye and base of mandible), with dense, short setae. Temple not swollen in dorsal view, smooth (with scattered punctations), with short, sparse setae. Frons smooth, flat, without carina between antennal socket, without lateral carina. POL 1.70x ocellar diameter, 0.83x OOL. Vertex smooth, punctate, with short, sparse setae. Occipital carina complete, joining hypostomal carina at mandible.

Mesosoma ( Figs 32, 35, 36 ). Pronotum punctate, dorsally without modifications. Ventral sides of pronotum laterally smooth. Mesosoma 1.44x as long as wide in lateral view, 1.37x as long as wide in dorsal view. Mesoscutum sharply raised anteriorly, at right angle with pronotum, medio-anteriorly areolate, median lobe without median groove anteriorly. Mesoscutum with short, sparse setae. Surface of mesoscutum medially areolate near scutellar sulcus, punctate elsewhere. Notaulus entirely absent. Mesonotal suture present and straight. Scutellar sulcus 7.50x as wide as long, 1.50x as long as scutellum, smooth. Scutellar sulcus with six complete carina. Scutellum laterally rounded, flattened in lateral view, areolate (laterally) but smooth medially. Subalar groove areolate. Mesopleuron areolate, with short, sparse setae. Precoxal sulcus absent. Surface of mesosternum weakly punctate-areolate. Propodeum 0.38x as long as mesosoma (in dorsal view), areolate, carinated areas completely absent anteriorly. Propodeum vertical posteriorly, with short, sparse setae. Propodeal transverse carina distinct (as high as neighboring sculpture) with two long spines laterally and two (sometimes acute) angles/tubercles medially; median tubercles short (as long as wide) and closer to each other than to lateral ones. Lateral spines 4x their transverse width, straight, with rounded apex. Surface of metapleuron areolate with short, sparse setae. Metapleural flange absent. Wings: Pterostigma 3.10x as long as wide. Marginal cell of fore wing closed distally. Vein r 0.60x as long as vein 3- SR, 0.16x as long as vein SR1, 0.36x as long as vein 2-SR. Vein 2-SR of fore wing present. Vein 1-SR+M absent. Vein r-m of fore wing with wide bulla. Vein cu-a of fore wing postfurcal. Vein CU1a (relative to vein 2-CU1 of fore wing) not interstitial, arising behind middle of distal vein of subdiscal cell (vein CU1a present basally as short sclerotized stub). Vein CU1b postfurcal with m-cu. First subdiscal cell of fore wing closed distally (vein 2cu-a present). Vein 2–1A long. Hind wing vein 1-SC+R present. Subbasal cell of hind wing distinctly enlarged. Hind wing vein M+CU 0.75x as long as vein 1-M. Hind wing vein r absent, m-cu absent. Basal cell of hind wing closed. Hind wing vein cu-a present. Legs: Femora not swollen. Hind coxa shortened, dorsally and ventrally smooth. Hind femur 3.50x as long as wide. Hind femur with sparse setae, dorsally and ventrally smooth (somewhat sparsely punctate). Hind tibia 5x as long as wide, 3x as long as hind basitarsus, without very long setae (not longer than tibia width), apically without specialized patch of setae on its inner side. Hind basitarsus 5x as long as wide, 0.65x as long as tarsomeres 2–5.

Metasoma ( Figs 32–34 ). Metasoma without visible sutures on carapace. Carapace longitudinally rugose-areolate anteriorly, areolate dorso-posteriorly, with transverse weak rugae apically in rear view. Carapace without apical opening. Carapace with short setae, its ventral opening 0.9x as wide as its full length. Ovipositor sheath 0.13x as long as metasoma. Ovipositor sheath apically weakly spatulate and with straight, short, thin setae.

Color. Scapus and pedicel yellowish, all flagellomeres brownish. Head blackish, mandible (excepted apex) and palpi yellowish, mandible apically brownish. Mesosoma blackish. Pronotum ventrally, tegula and apex of lateral spines on propodeum yellowish. Fore wing hyaline, veins and stigma yellowish. Coxae, femora, tibiae yellowish but hind tibia infuscate; fore tarsus yellowish, mid and hind tarsi strongly infuscate; hind tibial spurs whitish. Carapace mainly blackish apically, with long medio anterior rufous patch and presence on lighter small patch on the middle of carapace. Ovipositor sheath rufous.

Hosts records. None.

Morphological variation. Carapace with apical opening (on male) large and oval, opening 3x as long as wide. Rugae on vertex deeply impressed, face heavily punctate, hind coxa pale brownish latero-ventrally. The white patch on metasoma 0.60-0.80x as long as carapace length. Carapace baso-laterally often whitish.

Comments. Although more than 500 species (24 in Ethiopian region) have been described, the actual affinities of Chelonus (Microchelonus) spp. cannot be properly determined without a comprehensive revision. Chelonus (M.) matilei sp. nov. and C. (M.) merdicus sp. nov. together form a new species-group characterized by the presence of small lateral spine-like apophyses and a large dorsal white patch on carapace. We have seen at least two other undescribed taxa from Reunion differing in the shape of the apical opening of carapace, the apical sculpture of carapace, the sculpture on vertex, and the color of scapus and hind coxa. They superficially resemble Chelonus (Microchelonus) curvimaculatus Cameron, 1906 ( Figs 45–47) but the undescribed species from the Reunion have no propodeal spines.

Etymology. From the name of the collector, L. Matile.

Distribution record. Ethiopian ( Mauritius Island).

Type material. Holotype: Ψ ( MNHN): "Muséum Paris, Ile Maurice, Forêt de Macchabé, 19.III.1981, L. Matile". Paratypes: 2 ɗɗ ( MNHN), "Muséum Paris, Ile Maurice, Forêt de Macchabé, 19.III.1981, L. Matile"; Ψ (Cirad-PVBMT), Reunion "St Pierre / Bassin Martin, Station expérimentale de l’Armeflhor, parcelle AB, alt.

290m, XII.2010, tente Malaise"; ɗ (Cirad-PVBMT), Reunion "St Pierre / Montvert les Hauts, verger de manguiers AB Valatchy (partie non fauchée), alt. 600m, III. 2011, tente Malaise"; ɗ (Cirad-PVBMT) Reunion "St Paul / Tan Rouge, exploitation AB Glénac, alt. 800m, II.2011, tente Malaise". Additional material: ɗ (IDR), Reunion "St Denis / La Providence, sur fougère aigle, alt. 600m, II.2006, battage".

Figures

FIGURES 30 – 36. Chelonus (Microchelonus) matilei Braet & Rousse sp. nov., Holotype female. 30. full imago, laterally; 31. head, face; 32. propodeum and metasoma, laterally; 33. apex of metasoma; 34. metasoma, dorsal; 35. mesosoma with spines of propodeum, dorsal; 36. head and anterior part of mesosoma, dorsal.