Marilia qinlingensis, Morse, John C., 2017

Morse, John C., 2017, Lannapsyche and Marilia species of China (Trichoptera: Odontoceridae), Zootaxa 4320 (1), pp. 81-99 : 91-93

Marilia qinlingensis , n. sp.

( Fig. 9 )

Diagnosis. The new species is very similar to the widely distributed species M. sumatrana from Indonesia and M. parallela from southern China in having 1) the length of segment IX 1 /2 its height; 2) the lateromedian apical lobes blunt and each side of IX with only 1 longitudinal groove; and 3) each forewing with a concave subapical margin. However, the new species is easily separated from both species by (1) the forewings each having fork II sessile, originating at the short r-m crossvein; (2) the apex of male segment X being deeply divided into 2 broad lobes, their dorsal interlobular gap being in an elongate “V” shape; and 3) male tergum X has only one pair of median longitudinal ridges which meet each other at the tips, forming a clear, narrow, acute triangle. Additionally, it differs from M. sumatrana in that (1) the anterior margin of male segment IX is vertical, nearly straight and (2) the ventral margin of segment X on each side has a semicircular excision near the base. In contrast, M. sumatrana (as illustrated by Malicky 2010) has the anterior margins of segment IX with excisions on the ventral half; tergum X has the central ridges not meeting each other at the tips; and the ventral margins of segment X are straight, without excisions. It differs from M. parallela by (1) the longitudinal groove of each side of segment IX running horizontally into the anterior and posterior marginal rims; (2) the intersegmental depression between segments IX and X sloping gently; (3) the basal tube-like portion of the phallobase is only 2/5 of the total length of the phallus and (4) the phallotremal sclerites are large and highly sclerotized, with a deep “U” shape. In contrast, in M. parallela , the longitudinal grooves of segment IX run rather steeply ascendant backward, but do not reach the marginal rims; the intersegmental depression between segments IX and X is distinctive and the central ridges on the dorsum of segment X do not meet each other at the tips; and the basal tube-like portion of the phallobase is at least 1/2 of the total length of the phallus, and the phallotremal sclerites are cresentic with a wide opening and only moderate sclerotization.

Male (in alcohol). Body medium-sized, brown; palps pale yellowish; cephalic and thoracic setal warts pale yellowish; foreleg tibiae and tarsi dark brown, darker than those on mid- and hind legs. Forewing membranes brown with concave subapical margin. Vertex slightly constricted; interocular length about 2 times as long as least width. Vertexal medi-antennal compact setose warts not quite separate (meeting each other at distal half). Occipital compact setose warts large, triangular, positioned at posterior ends of coronal grooves. Pair of dark (nearly black), rounded bulges (= sensilla of Oláh & Johanson 2010?) located at inner anterior margins of occipital warts, close to their anterior tips.

Forewings ( Fig. 9 Fa) each with length 11.1 mm (n = 1); R1 fused with R2 near margin, at about same level as end of SC; origin of fork II basad of r-m crossvein. Single, unlooped anal vein with row of bristles ventrally. Hind wings ( Fig. 9 Fp) each with R1+R2 fused distally, strongly convex anteriorly and close to SC; base of R2 very short ( Fig. 9 Fp, arrow), R2 fused with R1 at level of anastomosis, similar to Marilia enikiana Oláh & Johanson 2010 ; M stem together with basal part of MP strongly sinuous and MP fused with Cu1 toward apex; Cu1 stem slightly concave anteriorly, not aligned with MP+Cu1, but joining MP+Cu1 at approximately 45° angle.

Male genitalia. Abdominal segment IX broadly rectangular in lateral view, pleural length = 1/2 of its height, dorsal margin of IX slightly longer than ventral margin ( Fig. 9A ); on each side dorsal lateroapical corner of tergum IX rounded ( Fig. 9A, l .api.corn.); below this corner deeply excised lacuna providing space for origin of preanal appendage, lateromedian apical lobe (l.m.lob.) almost identical with lateroapical corner; longitudinal groove horizontal, positioned at ventral 1/3 of segment IX, and extending onto anterior and posterior margins; dorsolateral longitudinal grooves absent ( Fig 9A ). Dorsal margin of segments IX and X sloping down gently without intervening declivity in lateral view. Segment X forming long, tall hood with apical 1/3 deeply incised into 2 rounded lobes in dorsal view, central ridges long, meeting each other at their tips and forming clear, narrow, acute triangle ( Fig. 9B ); in lateral view, each lobe appearing as sub-rectangular plate slightly longer than segment IX, apex narrowing to small, blunt, triangular lobe, ventral margin with semicircular excision near base ( Fig. 9A , arrow). Preanal appendages as long as segment IX, foliaceous, each usually dilated in middle then tapering to blunt tip ( Figs. 9A, 9B ), thin throughout length when viewed on edge (9BI). Inferior appendages about as long as segment X, much longer than preanal appendages in lateral view, directed caudodorsad and not reaching apex of segment X; each with coxopodite almost parallel-sided, not obviously broad at base, tapering slightly, and basomesal setose bump not distinctively protruding in ventral view ( Fig. 9C ); apical segment (harpago) short, cylindrical, not quite 2 times as long as wide in ventral view. Phallic apparatus composed of cylindrical phallobase curved gradually ventrad, phallicata retracted in our specimen, phallobase tube-like at basal 1/3, with apical 2/3 slightly enlarged and directed backward ( Fig. 9D ); phallotremal sclerite large, crescentic in lateral view ( Fig. 9D ), U-shaped in ventral view ( Fig. 9 Dv).

Holotype male. PR CHINA: Shaan-xi Province , North slope of Qin-ling Mountains, 20 km south of Bao-ji City, N33.9°, E108.8°, alt. 1000 m, 18 June 1998, Coll. Sun Ch-h., 1 male.

Etymology: Qinlingensis, name derived from Qin-ling Mountains, the type locality of the species.

Distribution: Oriental–East Palearctic Boundary Region of China (Shaan-xi, north slope of Qin-ling Mountains, N33.9°, E108.8°, alt. 1000 m).

Figures

FIGURE 9. Marilia qinlingensis, new species, male genitalia, head, and wings. 9 A – 9 D, male genitalia: 9 A, left lateral; 9 B, dorsal; 9 BI, right preanal appendage, viewed on ventrolateral edge; 9 C, ventral; 9 D, phallus, left lateral; 9 Dv, phallus, ventral. 9 E, head, dorsal. 9 Fa – 9 Fp, right wings, dorsal: 9 Fa, forewing; 9 Fp, hind wing.