Palpares longimaculatus

Akoudjin, Massouroudini & Michel, Bruno, 2011, A new species of Palpares Rambur (Neuroptera: Myrmeleontidae) with an identification key to the species of West Africa, Zootaxa 2792, pp. 33-40 : 34-37

Palpares longimaculatus nov. sp.

( Figs 1, 2 , 15 , 26, 27)

Diagnosis. Yellow head bearing a conspicuous black stripe on vertex and occiput extending to metathorax, and a light brown abdomen. Wing narrow. Membrane with pale markings in forewings, mostly restricted to some longitudinal and cross veins. Posterior margin of wings bordered by a conspicuous pseudo-fringe comprising a series of cells delimited by brown veins. In hind wing the longitudinal apical stripe reaches the level of the pterostigma. Terminal segment of labial palpus very slightly clavate at extremity with slit-shaped sensory opening. Gonarcus with a well developed, regularly rounded, hood-shape bulla.

Description. Forewing length: 3 45–54 mm; Ƥ 55–56 mm. Hind wing length: 3 41–50 mm; Ƥ 51–53 mm. Abdomen: 3 41–46 mm; Ƥ 33 mm.

Head. Face pale yellow. Vertex moderately inflated. Vertex and occiput light brown with a large brown longitudinal stripe extending on the membrane between head and prothorax. Apical segment of labial palpus yellowish, very slightly clavate and shortly pointed at apex. Palpimacula with slit-like opening, limited to clavate part ( Fig. 15 ). Antennal scape yellow. Pedicel light brown. Flagellomeres black.

Thorax. Pronotum yellow with a median brown stripe. Brown laterally. Anterior and posterior margin with long thin light brown setae. Mesothorax yellow with a broad median brown stripe and two lateral narrower brown stripes on mesoscutum. Metathorax yellow with a median brown stripe and two light brown spots on the disc of the metascutum. Meso and metathorax covered laterally with dense long white setae.

Legs. Coxae yellow. Femora yellow, brown dorsally. Tibiae coloration uniform varying from yellowish to light brown. Anterior tibiae paler. Tarsi dark brown.

Wing. Narrow, with the posterior margin slightly less convex in female than in male. Fore and hind wings with a well delimited row of cells along the posterior margin, like a pseudo-fringe, extending from origin of recurrent vein to middle of apical stripe, not reaching apex of wings. Membrane hyaline with most longitudinal veins entirely or mainly brown except branches of Rs which are brown apically only. Remaining longitudinal and cross veins pale. Hind wing with more conspicuous markings, the first marking close to origin of the recurrent vein extending from M1 to first branch of recurrent vein, paler between anterior branch of M2 and recurrent vein. Second marking discal, limited by Rs and 3rd branch of recurrent vein. Third marking between branches of Rs fork. Fourth marking striped, extending from level of pterostigma to apex of wing, separated from precedent marking by one or two rows of cells only ( Fig. 2 ).

Abdomen. Light brown. Each tergite variably darker dorsally. Male tergites II to IV with long slender erect setae becoming stouter on distal part of tergite IV. Tergites V and VI with lateral pilosity only. Tergites VII and VIII glabrous. In female all setae are short and stout except laterally on tergite II where they are longer and more slen- der. Ectoproct of male slightly curved with two stout spine-like setae at base of the post-ventral lobe and a brushlike patch of stout setae on inner surface extending on the distal half ( Fig. 1 b). Gonarcus with well-developed hood-like bulla ( Figs 26, 27).

Type material. Holotype 3, BURKINA FASO, Bobo-Dioulasso (11°07’ N – 04°42’W), 04.vi.2009, light-trap between 07:00 p.m. and 10:00 p.m. (coll. CIRAD). Paratypes. 3 3 and 2 ƤƤ, same data as holotype, except one male collected with entomological net at 05: 30 p. m.

Additional material. SENEGAL, 13, Tiaroye (14°44’N – 17°21’W), vi.1923, Millet-Horsin ( MNHN); 1Ƥ, M’Bayakh (= Bayakh) (14°49’N – 17°08’W), 19.vii.1982, Niayes region, B. Sigwalt leg. ( MNHN); 1Ƥ (picture), Noflaye (14°47’N – 17°12’W), vii.1971 (coll. A. Prost) (this specimen is figured as P. radiatus in Prost, 1995).

Distribution and biology. To date, specimens of Palpares longimaculatus nov. sp. have only been recorded from the region of Dakar and from Bobo-Dioulasso ( Fig. 6 ); it is not known whether these populations are contiguous or isolated from each other. Despite the intensive prospecting carried out during six years by the second author, P. longimaculatus nov. sp. has never been collected in the region of Sikasso in southern Mali ( Michel, 1999) which is only 170 km from Bobo-Dioulasso and with quite similar climatic conditions. In Senegal the collection localities are located in the extreme South of the Niayes region where the climate is characterised by the alternation of a dry season from October to June and a rainy season from July to September, with an annual rainfall of around 400 mm. The climate here is quite different from the region of Bobo-Dioulasso, where the rainy season extends from May to October with an annual rainfall of around 1000 mm. Despite the low rainfall, the Niayes region is characterized by high relative humidity due to the proximity of the ocean and to the exposure of the water table. This region was previously more humid than at present and it is known for harbouring Sudano-Guinean relictual species of plants that persisted during the successive climatic conditions since the early Holocene (ca. 10,000 years BP) ( Lézine, 1989; Lézine & Chateauneuf, 1991; Maugis et al., 2009). This could be the case for the population of P. longimaculatus nov. sp., but knowledge of the distribution of Myrmeleontidae in West Africa is too poor to make clear conclusions. In Burkina Faso P. longimaculatus nov. sp.was collected in association with P. spectrum in dry savanna. It should be noted that in southern Mali the intense collecting showed that P. spectrum is often associated with P. incommodus . The larva is unknown.

Etymology. Referring to the length of the apical stripe of the wings.

Remarks. Palpares longimaculatus nov. sp. is very similar to P. kalahariensis ( Fig. 3 ) from South Africa. These species can be distinguished by the length of the apical stripe in the wings, the shape of the last palpomere of the labium ( Figs 15, 16 ) and the shape of the gonarcus-parameres complex ( Figs 26, 28). In the female of P. k a l a - hariensis, the posterior margin of the wings is more convex than in P. longimaculatus . In the two specimens of P. kalahariensis we examined the wing markings are more extensive and conspicuous than those of P. longimaculatus ( Figs 1, 2, 3 ). The male of P. radiatus very strongly resembles P. longimaculatus ( Figs 1, 4 ), but it can be distinguished from the latter by the following characters: distal palpomere of labium more enlarged on the distal third ( Figs 15, 17 ), apical stripe of hind wing short, shape of the gonarcus-parameres complex which was similar to the figure published by Prost (1995) ( Figs 26, 29) in the male from Mali we dissected. P. longimaculatus can be distinguished from P. incommodus by the following characters: presence of a conspicuous pseudo-fringe along the posterior margin of the wings ( Figs 1, 2 , 7), the less slender distal palpomere of labium and the rounded gonarcal bulla of male ( Figs 26, 30).

FIGURES 7–14. Palpares spp. 7— P. incommodus 3; 8— P. cephalotes 3 (coll. MNHN); 9— P. obsoletus 3; 10— P. zebroides Ƥ (coll. MNHN); 11— P. digitatus Ƥ; 12— P. umbrosus Ƥ; 13— P. percheronii 3; 14— P. nigrescens 3.

Figures

FIGURE 6. Collect localities of Palpares longimaculatus.

FIGURES 1 – 5. Palpares spp. 1 a— P. longimaculatus, holotype 3; 1 b— P. longimaculatus, right ectoproct, inner face; 2 — P. longimaculatus, paratype Ƥ (as = apical stripe); 3 — P. kalahariensis Ƥ (from South Africa); 4 — P. radiatus 3; 5 — P. radiatus Ƥ (coll. MNHN).

FIGURES 15 – 25. Distal palpomere of labium. 15 — P. longimaculatus; 16 — P. kalahariensis; 17 — P. radiatus; 18 — P. i n c o m - modus; 19 — P. cephalotes; 20 — P. obsoletus; 21 — P. digitatus; 22 — P. umbrosus; 23 — P. zebroides; 24 — P. percheronii; 25 — P. nigrescens.