Helicopsyche melina, Johanson & Pham, 2012

Johanson, Kjell A. & Pham, Hong-Thai, 2012, Three new species of Helicopsyche (Trichoptera, Helicopsychidae) from northern Vietnam, with a key to Helicopsyche species of Vietnam, European Journal of Taxonomy 6, pp. 1-10 : 2-4

Helicopsyche melina sp. nov.

Fig 1

Diagnosis

Helicopsyche melina sp. nov. is most similar to H. admata Malicky & Chantaramongkol, 1992 , H. dacklestenensis Schefter & Johanson, 2001 and H. nastia Malicky & Melnitsky ( Melnitsky & Malicky 2008) particularly due to the presence of four-segmented maxillary palps in combination with the nearly similar shape of the gonopods and tergum X in lateral view. The new species is easily distinguished from these by the presence of a well-developed transverse plate of segment IX located at mid-height of posterior part of the segment; the primary branch of each gonopod is produced anterad; and the secondary branch of each gonopod is long, straight, and oriented in right angle to the primary branch of the gonopods.

Etymology

Melina, named after the Melinh Station for Biodiversity, near the type locality.

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 IP7].

Paratypes ♂

VIETNAM: 8 ♂♂, Vinh Phuc Prov, Me Linh Distr, stream near Ngoc Thanh Village, 21°23'40.1"N, 105°42'54.9"E, light trap 5 Apr. 2011, loc# VN 008, leg. K.A. Johanson, P.H. Thai & T. T. Du ( IEBR, alcohol); 241 ♂♂, Vinh Phuc Prov, Me Linh District, stream near Ngoc Thanh Village, 21°23'48.4"N, 105°42'56.1"E, 186 m, Malaise trap 5-12 Apr. 2011, loc# VN 006, leg. K.A. Johanson, P.H. Thai & T. T. Du ( NHRS, alcohol); 20 ♂♂, Vinh Phuc Prov, Me Linh District, stream near Ngoc Thanh Village, 21°23'48.4"N, 105°42'56.1"E, 186 m, Malaise trap 5-12 Apr. 2011, loc# VN 006, leg. K.A. Johanson, P.H. Thai & T. T. Du ( IEBR, alcohol); 34 ♂♂, Vinh Phuc Prov, Me Linh Distr, stream near Ngoc Thanh Village, 21°23'38.9"N, 105°42' 50.7"E, light trap 4 Apr. 2011, loc# VN 002, leg. K.A. Johanson, P.H. Thai & T. T. Du ( NHRS, alcohol); 2 ♂♂, Vinh Phuc Prov, Me Linh Distr, stream near Ngoc Thanh Village, 21°23'58.7"N, 105°42'49.8"E, light trap 5 Apr. 2011, loc# VN 007, leg. K.A. Johanson, P.H. Thai & T. T. Du ( NHRS, alcohol).

Description

MAXILLARY PALPS. Four-segmented, each segment gradually shorter distally. Pair of interantennal setal warts bean shaped, each about as long as width of individual scapus. Each scapus about as long as each basal segment of maxillary palps. Spur formula 1,2,4; each foreleg spur slightly shorter than each first tarsomere.

LENGTH. Forewing 2.8-3.6 mm, hind wing 2.3-2.9 mm (N = 10).

MALE ABDOMEN AND GENITALIA. ( Fig. 1 ) Sternal process VI about one-fifth as long as sternum VI, straight, oriented posteroventrad; slightly tapering in lateral view ( Fig. 1A ); with slightly club-shaped apex in ventral view ( Fig. 1B ). Segment IX about as long as high in lateral view ( Fig. 1C ); each anterior lobe of segment IX ( Fig. 1C ) narrowly and symmetrically ellipsoid in lateral view, oriented anterad; anterodorsal and anteroventral margins almost straight ( Fig. 1C ); in dorsal view, inner margin forming narrowly ellipsoid cavity ( Fig. 1D ); in ventral view, without central posterior process ( Fig. 1E ); inner margin forming nearly triangular cavity; lateral apodemes nearly horizontal ( Fig. 1C ), widening anteriorly, meeting anterior margin, sub-marginal line absent; tergal transverse apodemes well-developed; sternal transverse apodeme absent. Transverse plate of segment IX located at mid-height of posterior margin of segment IX; in lateral view almost club-shaped, curving ventrad ( Fig. 1C ); in ventral view forming broadly heart-shaped plate above basal part of gonopods ( Fig. 1E ). Tergum X, in lateral view, oriented posterad ( Fig. 1C ), almost straight, tapering along its length; apex strongly pointed ( Fig. 1D ); in dorsal view ( Fig. 1D ), deeply divided into pair of tapering, divergent branches, with about 3 pairs of equally long megasetae in apical group, starting opposite to apex of gonopods in lateral view ( Fig. 1C ). Superior appendages tubular ( Fig. 1D ), slightly curving dorsally. Primary branch of gonopods, in lateral view ( Fig. 1C ), oriented dorsally, broadened distad to mid-height; anterior margin smooth, strongly concave; dorsal and posterior margins edged, undulating, posteroventral margin almost straight ( Fig. 1C ); apices produced mesad into rounded lobes above basolateral part of tergum X. Secondary branch of gonopods nearly as long as secondary branch of gonopods; slender, almost straight in lateral view, except apex slightly curving dorsad; with few setae; curving mediad in ventral view ( Fig. 1E ). Basomesal lobes absent. Basal plate, in lateral view ( Fig. 1C ), nearly straight, narrowing along its length, slightly produced beyond anteroventral margin of segment IX in lateral view ( Fig. 1C ); narrow in ventral view ( Fig. 1E ). Phallic apparatus, lateral view, tube-shaped along its length ( Fig. 1F ), narrowest shortly after basis, apex about as broad as base; nearly straight after mid-length; in ventral view, with basis narrow ( Fig. 1G ); widest immediately after mid-length; endotheca weakly produced, posteroventral part not sclerotized, except pair of weakly sclerotized pair of triangular processes distally of phallic sclerite.

Figures

Fig. 1. Helicopsyche melina 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.