Petrothrincus tsaratananensis, Johanson, Kjell Arne & Oláh, János, 2006

Johanson, Kjell Arne & Oláh, János, 2006, Eleven new species of Sericostomatoidea from Madagascar (Trichoptera: Helicopsychidae, Petrothrincidae, Sericostomatidae), Zootaxa 1205, pp. 1-30 : 12-13

Petrothrincus tsaratananensis , new species

Figs 17–19 , 28–31 , 59

This new species is very close to P. steineri , P. weaveri , P. newidop , new species, and P. andring , new species, in genitalia, especially in having a 3­branched gonocoxite. P. tsaratananensis is, however, unique and easily distinguished from the others by having interantennal setal warts on the head slightly produced; IXth tergum well defined but short; apex of apical lobe of Xth tergum well developed, short, and not bifid; gonocoxite branches of characteristic shape; and, in ventral view, the median margins of the gonocoxite running parallel; the three pairs of spine­shaped phallic sclerites approximately equal in length; the phallus slightly more angled; and the posterior apex of the phallic guide more rectangular and with incisions on the posterior apex.

Male head and thorax ( Figs 17–19 ). Scape about 3x as long as wide ( Fig. 17 ). Maxillary palp ( Fig. 18 ) 5­segmented, 1st segment 2x longer than wide, 2nd segment about as long as 3rd segment and as long as wide, 3rd segment shortest, 4th segment 2x longer than 1st segment, 5th segment as long as 3rd and 4th together. Labial palp ( Fig. 19 ) about as long as maxillary palp segments 1–4 together. Interantennal warts close to each others and slightly produced anteriorly ( Fig. 17 ), cephalic warts reniform, postocular warts long vertical. Pronotum narrow with small, oval lateral setal warts and median setal warts about 2x longer than lateral setal warts.

Male wings. Forewing length 5 mm, hind wing length 3.8 mm. Denuded wing membrane pale flavous with pale helveus veins. Venation typical. Discoidal cell 1.7x longer than wide. Subcosta and, particularly, radius on forewing and subcosta on hind wing strongly thickened. Pterostigmal area enlarged and well pigmented.

Male genitalia ( Figs 28–31 ). Anterior margin of segment IX ( Fig. 28 ) bluntly triangular, almost semicircular, anterodorsal and anteroventral margins about equally strongly concave, posterior margin concave with a triangular upper lobe in lateral aspect ( Fig. 28 ). IXth tergum very short ( Fig. 28 ). Xth tergum, dorsal view ( Fig. 29 ) triangular basally, a short apical lobe with rounded apex and 2 short apical setae; lateral view ( Fig. 28 ) apical lobe curving slightly downward. Superior appendage of segment X broader towards truncate apex, digitate with large tubercles along posterior margin ( Fig. 28 ) and with long setae basally supported by a wide, dorsal plate ( Fig. 29 ). Gonocoxite tripartite distally and generally oriented dorsally ( Fig. 28 ), dorsal branch slightly curving posteriorly and with rounded apex; middle branch longer than dorsal branch, more strongly pointed apically and bent ventrally; ventral branch short, wide and rounded apically; in ventral view ( Fig. 31 ) with long median margin of gonocoxite. Phallic guide posteriorly slender in lateral view ( Fig. 28 ); in ventral view ( Fig. 31 ) generally wide along its length, apex broadly and deeply divided forming pair of incised lateral projections directed laterally. Phallus, lateral view ( Fig. 28 ) with basal one third equally wide and widens before midway before tapering towards apex. In ventral view ( Fig. 30 ) with basal one third narrowest. Phallic sclerites form 3 pairs, the anterior pair slightly shorter than the other pairs ( Figs 28, 30 ).

Etymology. The species is named after the type locality, Mt Tsaratanana on Madagascar.

Holotype male: MADAGASCAR: Mt Tsaratanana, 500 m, no date [R. Paulian].

Paratypes: MADAGASCAR: Mt D’Ambre, Les Roussettes. [B. Stuckenberg] — 5 males, 2 females (NRM alcohol); ditto, except — 4 males, 2 females (JOS alcohol); MADAGASCAR: Andohahela, i. 1954 [R. Paulian] — 1 male, 1 female (NRM).

Figures

FIGURE 59. Map of Madagascar showing distributions of Petrothrincus spp. (Petrothrincidae): P. newidop, P. pauliani and P. tsaratananensis (circle); P. dhritaparam (rectangle); P. andring (diamond); P. scottae, P. weaveri, P. s t e i n e r i, P. acuta and P. concava (cross); and P. andohel and P. tsaratananensis (triangle).

FIGURES 17 – 27. Petrothrincus spp. Male head and thorax: 17 – 19. Petrothrincus tsaratananensis, new species, holotype. 17 — head and thorax, dorsal; 18 — maxillary palp; 19 — labial palp. 20 – 21. Petrothrincus pauliani, new species, holotype. 20 — head and thorax, dorsal; 21 — maxillary palp (broken). 22 – 24. Petrothrincus andohel, new species, holotype. 22 — head and thorax; 23 — maxillary palp lateral; 24 — maxillary palp, dorsal. 25 – 27. Petrothrincus andring, new species, holotype. 25 — head and thorax, dorsal; 26 — maxillary palp, dorsal; 27 — maxillary palp, lateral.

FIGURES 28 – 31. Petrothrincus tsaratananensis, new species, holotype. Male genitalia: 28 — genitalia, lateral; 29 — genitalia, dorsal; 30 — genitalia, ventral; 31 — phallus, ventral.