Three new species of Helicopsyche (Trichoptera, Helicopsychidae) from northern Vietnam, with a key to Helicopsyche species of Vietnam Author Johanson, Kjell A. Author Pham, Hong-Thai text European Journal of Taxonomy 2012 2012-02-02 6 1 10 journal article 22222 10.5852/ejt.2012.6 4474424d-176b-4799-b758-85f890cedb7a 3822694 164C48C6-78C5-413D-BCCD-304147AB9896 Helicopsyche lamnata sp. nov. Fig. 3 Diagnosis Helicopsyche lamnata sp. nov. is most similar to H. vongsombathi Johanson & Malm, 2007 , from which it is easily distinguished by the presence of a central posterior process of segment IX and the distal part of the gonopods are more strongly produced posteriorly. The species also resembles H. meander sp. nov. , particularly by the nearly club-shaped apex of tergum X in lateral view, but in H. lamnata sp. nov. the VIth sternal process is much longer and the gonopods are less sharply sigmoid. Etymology Lamnata , plate-like in Latin, refers to the process on the posterior margin of sternite IX. Material examined Holotype ♂ VIETNAM : Vinh Phuc Prov , Me Linh District , stream near Ngoc Thanh Village , Melinh Station for Biodiversity , 21°23'28.2"N , 105°42'46.7"E , 233 m , Malaise trap 4-12 Apr. 2011 , loc#VN001, leg. K.A. Johanson , P.H. Thai & T.T. Du ( NHRS , alcohol) [DNA voucher IP9]. Paratype Same data as holotype , except ( IEBR , alcohol). Description MAXILLARY PALPS. Two-segmented, all segments sub-equal in length. Pair of interantennal setal warts very large, spherical, elevated, densely covered by long setae. Each scapus slightly longer than individual segments of maxillary palps. Spur formula 1,2,4; each foreleg spur nearly as long as each first tarsomere. LENGTH. Forewing 4.0 mm, hind wing 3.1 mm (N = 1). MALE ABDOMEN AND GENITALIA. ( Fig. 3 ) Sternal process VI about two-fifths as long as sternum VI, straight, oriented posteroventrad; parallel-sided in lateral view ( Fig. 3A ); almost parallel-sided in ventral view ( Fig. 3B ). Segment IX slightly taller than long in lateral view ( Fig. 3C ); each anterior lobe of segment IX ( Fig. 3C ) smoothly narrowing anteriorly in lateral view, asymmetrical, oriented anterodorsad; anterodorsal margin almost straight; anteroventral margin concave ( Fig. 3C ); in dorsal view, inner margin forming narrowly ellipsoid cavity ( Fig. 3D ); large central posterior process located below basis of gonopods, sharply triangular in lateral view ( Fig. 3C ); in ventral view widely trapezoid, with slightly concave posterior margin. Lateral apodemes nearly horizontal ( Fig. 3C ), parallel-sided along their length, located at mid-height of segment IX, ending in sub-marginal line; tergal transverse apodemes absent; sternal transverse apodeme oriented in right angle to lateral apodeme, located along posterior margin of segment IX ( Fig. 3C ). Transverse plate absent. Tergum X, in lateral view, oriented posteroventrad ( Fig. 3C ), strongly tapering towards mid-length, with single, dorsolateral, stout seta at mid-length; distal half almost parallel-sided, apex slightly club-shaped, orienting posteroventrally ( Fig. 3C ); in dorsal view ( Fig. 3D ), deeply and narrowly divided into pair of parallel-sided and parallelrunning branches; each with 4 pairs equally long megasetae in apical group, and two pairs stout, posteradoriented spines ( Fig. 3C ). Superior appendages club-shaped ( Fig. 3C ), oriented posteroventrad. Primary branch of gonopods, in lateral view ( Fig. 3C ), with basal part oriented posterad before strongly bending posterodorsad, curving posterad after mid-length, apical part rounded in dorsal view; produced mesad into pointed plates above tergum X in dorsal view ( Fig. 3D ); slightly widening along their length; basal part of anterior margin smooth; dorsal and posterior margins undulating. Secondary branch of gonopods absent. Basomesal lobes long, slightly broadening before apex, each with pair of apical setae; straight in lateral view ( Fig. 3C ), diverging in ventral view ( Fig. 3E ). Basal plate, in lateral view ( Fig. 3C ), straight, strongly narrowing anteriorly towards mid-length, anterior half very slender, not produced beyond anteroventral margin of segment IX in lateral view ( Fig. 3C ); almost parallel-sided in ventral view ( Fig. 3E ), with rounded anterior apex. Phallic apparatus, lateral view, irregularly tube-shaped along its length ( Fig. 3F ), apex about as broad as base; nearly straight after mid-length; irregular in ventral view ( Fig. 3G ); widest after mid-length; endotheca weakly produced, posteroventral part not sclerotized, except long, single, weakly sclerotized triangular processes distally of phallic sclerite. Fig. 3. Helicopsyche lamnata sp. nov. , ♂ holotype. A . abdominal sternum VI, lateral view. B . abdominal sternal process VI, ventral view. C . genitalia, lateral view. D . genitalia, dorsal view. E . genitalia, ventral view. F . phallus, lateral view. G . phallus, ventral view. Key to male Helicopsyche from Vietnam 1. Maxillary palps each with two segments; gonopods without secondary branch...................................2 – Maxillary palps each with four segments; gonopods with secondary branch.......................................6 2.(1) In genitalia, basomesal lobe absent (as in Fig. 1C ).... H. boniata Malicky & Chantaramongkol, 1992 – In genitalia, basomesal lobe present ( Fig. 2C )......................................................................................3 3.(2) In genitalia, basomesal lobe originated from ventral part of gonopod basis, resembling secondary branch of gonopods (as in Schefter & Johanson 2001 , figs 5, 9)........................................................4 – In genitalia, basomesal lobe originated from mid-height of gonopod basis ( Fig. 2C )........................5 4.(3) In genitalia, segment IX about as long as high; tergum X slender along its length in lateral view; in ventral view basomesal lobes fused mesally into common basal plate; in dorsal view, tergum X shallowly divided apically............................................... H. khemoiensis Schefter & Johanson, 2001 – In genitalia, segment IX much higher than long; tergum X wide and posteriorly tapering in lateral view; in ventral view basomesal lobes separated; in dorsal view, tergum X deeply divided apically...... ............................................................................................................... H. azwudschgal Malicky, 1995 5.(3) Sternite VI with sternal process about two-fifths as long as segment VI ( Fig. 3A ); posteroventral margin of segment IX produced posterad into large plate ( Figs 3C, E ); gonopods slightly sigmoid ( Fig. 3C )................................................................................................................... H. lamnata sp. nov. – Sternite VI with sternal process about one-seventh as long as segment VI ( Fig. 2A ); posteroventral margin of segment IX not produced posterad ( Fig. 2E ); gonopods strongly sigmoid, bending about 90° ( Fig. 2C )................................................................................................................ H. meander sp. nov. 6.(1) In genitalia, dorsal branch of gonopods almost parallel-sided in lateral view.................................... ..................................................................................... H. admata Malicky & Chantaramongkol, 1992 – In genitalia, primary branch of gonopods widening distally in lateral view ( Fig. 1C )......................7 7.(6) In genitalia, primary branch of gonopods produced anterad ( Fig. 1C ).............. H. melina sp. nov. – In genitalia, primary branch of gonopods produced posterad.............................................................8 8.(7) In genitalia, primary branch of gonopods shorter than secondary branch of gonopods; each lateral branch of tergum X divided apically............................................................... H. angusta Ulmer, 1951 – In genitalia, primary branch of gonopods longer than secondary branch of gonopods; each lateral branch of tergum X undivided apically.................................. H. dacklestenensis Schefter & Johanson, 2001