Madagocerum bhemi, Oláh & Johanson, 2011

Oláh, J. & Johanson, K., 2011, Description Of A New Endemic Genus Of Trichoptera From Madagascar (Odontoceridae), Acta Zoologica Academiae Scientiarum Hungaricae 57 (2), pp. 117-129 : 121-123

Madagocerum bhemi sp. n.

( Figs 1–4 )

Diagnosis –This species is most similar to M. idvigun sp. n. in having a short segment IX. It is distinguished from M. idvigum by the broader, blunt and divergent preanal appendages in dorsal view, not narrow, tapering and tangential; segment X is shorter than the preanal appendages, not longer; the coxopodites have no apicodorsal spiny protuberance; the harpagones are narrow, not broad; and the phallic apparatus is broad, not narrowing apically.

Description – Male (in alcohol). Body dark brown, except paler ventrally; cephalic and thoracic appendages light brown; forewing membrane light brown, without pattern (in alcohol).

Wings ( Fig. 1 ): Forewing apex narrowly rounded; 5.0 mm; membrane light brown; termen slightly convex; basal lobe present covered by microtrichia; jugum absent. Forewing forks I, II, III, and V present; Sc running to R1, and R1 running to R2 before C, meeting at hypertrophied pterostigma; distally almost indiscernible; Cu2 apparently absent in forewings; postanal vein running closely to posterior wing margin.

Male genitalia ( Figs 2–4 ): Abdominal segment IX fused annularly, short in lateral view, particularly at dorsal 1/3rd; venter 3 times longer than dorsum; anterior margin convex in lateral view, with lateral concavity conspicuous in dorsal view; posterior margins concave, with small, subtriangular apical lobe at dorsal margin of coxopodites; each antecosta and antecostal suture narrow on anterior margin of segment IX, forming pigmented marginal rim running evenly along anterior margin; acrotergite absent; surface of segment IX glabrous, spine row absent on posterior margins. Intersegmental depression between segments IX and X very deep, stepwise; segment X sunk to upper 1/3rd of segment IX, visible in lateral view; intersegmental depression covered by fused base of preanal appendages. Segment X broadly rod-like, directed straight posterad. Apicoventral setose lobes represented by setose apex of segment. Apicodorsal setose lobes reduced to central areas with scattered setae. Segment X body deeply cleft, with tangential lobes. Dorsal interlobular gap filled, as seen in dorsal view. Large, deeply bilobed preanal appendages dominating above phallic apparatus; fused basally; horizontal, posterad directed lobes fused to dorsum of segment IX; fused seam, representing borderline between segment IX and preanal appendages indiscernible; in lateral view, dorsal and ventral margins straight, producing regular, parallel-sided rods. Preanal appendages divergent in dorsal view, parallel-sided; rod-like. Coxopodites robust, dorsal margins rounded, convex; ventral margins concave, ending in small apicoventral corners. Harpagones slender, constricted at mid-length; capitate, with mesad turning apex with few, dark, short, conical spines. Phallic apparatus with broad, ventrally directed, short basal part; horizontal apical part long, straight. Small phallotremal sclerites almost indiscernible.

Material examined – Holotype: Male: “ Madagascar: Andohahela: 1800 m, i.1954 [Paulian]”.

Paratype: 1 male: same data as holotype .

Etymology: Bhemi, slender in Sanskrit, named after the slender harpagones in this species compared to in other species in the genus.

Figures

Figs 1–4. Madagocerum bhemi gen. et sp. n., holotype:1 = right wings, 2 = genitalia, lateral view, 3 = genitalia, dorsal view, 4 = phallus, lateral view