Neophylax obliquostriatus, Mey & Malicky, 2021

Mey, Wolfram & Malicky, Hans, 2021, Caddisflies from Myanmar: New records and descriptions of new species (Insecta, Trichoptera), Zootaxa 5060 (4), pp. 533-565 : 543-545

Neophylax obliquostriatus spec. nov.

( Figs 8A–8H , 17 )

LSID urn:lsid:zoobank.org:act:E3A41D16-A70F-4A49-BEFD-206483940423

Holotype ♂ and 4 ♀ paratypes (pinned), Myanmar, Kachin State, Kanphant , 40 km north, 3-river-junction, 1970– 2450 m, 26°23’12.7”N 98°39’36.6”E, 2–3.x.2010, holotype genitalia in glycerine vial, leg. S. Naumann ( MfN).

Etymology. Latin, obliquus, “oblique” (adjective), striatus, “striated” (participle), referring to the white oblique striae in the anal areas of the forewings.

Diagnosis. With respect to the forewing pattern the new species resembles specimens collected in Gansu, China, which were identified as N. maculatus ( Forsslund 1935) . That species was described from a series of 5 females. The illustrations of the female genitalia are informative enough to exclude conspecificity with the new species; the hump-like lateral processes of segment X of the new species are absent in N. maculatus and the lateral vulval lobes are half as long as segment X in the new species and nearly as long as segment X in N. maculatus . Neophylax fenestratus ( Banks 1940) , from Sichuan, China, also was described from females; the structures of the genitalia of the new species differ from the female figures of Banks (1940: pl. 29, fig. 53) by much shorter lateral humps and the convex dorsal side of segment X in lateral view in the new species. Malicky (2016) illustrated the male genitalia of an individual from Yunnan, which he associated tentatively with N. fenestratus ; his male figures (2016: p. 25) differ by the shape of segment X in lateral view, especially the straight posterior edge of its external branch in the new species. The illustrations of the female holotype of N. tenuicornis ( Ulmer 1907) show excavated dorsal sides of the lateral lobes of segment X forming a dorsal groove, which is an unusual character not observed in the new species or in any of the other Asian species of the genus. The male hind wings of the new species bear long, white hairs emanating in opposing directions from R1 towards Cu2 and from Cu1b towards M1+2. They cover a pocket of flavescent, curved, androconial hairs between M3+4 and Cu1a.

Description. Length of each forewing 15–16 mm. Forewings brown, with scattered grey-white spots in membrane carrying short, yellow hairs, also present on veins of anal loop, two diverging white striae present between Cu1 and A1, crossing Cu2 without interruption; this forewing pattern similar in both sexes ( Fig. 17 ). Head and thorax black; eyes hemispherical; ocelli white; frontal, occipital and pronotal warts with long, black setae; palpi and scapes brown, flagellomeres brown, with light patches on ventral sides. Legs brown, ventral groove on each femur present, praetarsus with pair of ventral spines, spurs 1.3.3.; inner, apical spur of each hind femur modified ( Fig. 8H ). Forewings each with nygmatas at base of fork 2 and in thyridial cell ( Fig. 8A ). Hind wing venation of females with closed discoidal cell and only two M veins; venation of male hind wings modified ( Fig. 8A ), comprising open discoidal cell, androconial pocket in the middle of M veins, and long hairs on R1 and Cu2; two frenular bristles present in males, four in females.

Male genitalia ( Figs 8E–8G ). Segment IX in ventral view broad, with narrow V-shaped notch anteriorly, and extended distally in broad, squarish median lobe; dorsal part in lateral view reduced to narrow strap, not clearly separated from segment X. Dorsal parts of inferior appendages club-shaped, directed posterodorsady, basoventral parts curved mesad to form quadrangular, median lobes. Segment X with pair of long internal branches angled apically and curved laterad, each with broad, rounded extension on dorsal side; external branches broadly fused to internal branches forming deep cavities on posterior sides. Phallic apparatus small, membranous.

Female genitalia ( Figs 8B–8D ). Segment IX narrow, ring-like, forming broad, tri-lobed vulvar scale on ventral margin; lateral vulval lobes digitiform, bent medially with apices abruptly curved ventrad. Segment X divided into two broad, lateral lobes, becoming slender and rounded at apices; each with short hump-like lateral process.

Remarks. Neophylax tenuicornis is the type species of the concomitantly established genus Halesinus Ulmer1907. The holotype is a female collected in China, with the label “Ta-tsien-Lou, native collector, 1892”. The description is very detailed and provides a number of unique characters, especially from the external morphology of the genitalia, which are clearly different from the new Kachin species. The wing venation, colour and wing pattern, however, are very similar in these two species. According to the descriptions of other congeners, the external appearance of adults seems to be a unifying feature diagnostic for the genus.

A closer inspection of species of Neophylax McLachlan 1871 has revealed the synonymy of Neophylax nigripunctatus Tian & Li 1993 (in Tian et al. 1993) with Phylostenax Mosely 1935 , and very probably with P. himalus Mosely 1935 . The male genitalia exhibit only insignificant differences. The species is excluded here from Neophylax .

Figures

FIGURE 8. Neophylax obliquostriatus spec. nov., scale = 2 mm.: 8A, male right forewing venation, dorsal, scale = 2 mm; 8B–8D, female genitalia, scale = 0.5 mm: 8B, left lateral; 8C, dorsal; 8D, ventral. 8E–8G, male genitalia, scale = 0.5 mm: 8E, left lateral; 8F, dorsal; 8G, ventral. 8H, apical spurs of male right hind tibia, mesal.

FIGURE 17. Neophylax obliquostriatus spec. nov., female paratype, scale bar: 5 mm.