Rhyacophila linguiformis, Sun, 2017

Sun, Changhai, 2017, Two new species of the Rhyacophila nigrocephala species group from China (Insecta, Trichoptera, Rhyacophilidae), European Journal of Taxonomy 300, pp. 1-10 : 4-5

Rhyacophila linguiformis sp. nov.

urn:lsid:zoobank.org:act:A2708F26-9F2B-49C3-BCA2-D18F180A2FF9

Fig. 1

Diagnosis

This new species is similar to R. rima Sun & Yang, 1995 from Jiangxi, China and R. esorima Mey, 1996 from Vietnam in the male genitalia, all of them belong to the R. manuleata sub-group, but the new species differs in: (1) the complex of preanal appendages and the dorsal lobe of segment X in dorsal view is progressively narrowed from the base to the apex, but in R. rima the complex is somewhat spindleshaped, and in R. erorima the complex with two parallel lateral margins, which become narrow near the apex; (2) the anal sclerites in lateral view are shorter than the complex, with the apex moderately concave in dorsal view, but in R. rima it extends beyond the apex of the complex, with a deep incision mesally in dorsal view, and in R. esorima it extends to the complex, with the apex slightly incised mesally; (3) the gap between the upper and the lower lobes of each inferior appendage is smaller than the width of the lower lobe, but in both R. rima and in R. esorima the gap at least equals the width of each lower lobe.

Etymology

The species epithet comes from the Latin word “ linguiformis ”, meaning “tongue-shaped”, in reference to the tongue-shaped complex of the preanal appendages and the apicodorsal lobe of segment IX.

Type material

Holotype

CHINA: ♂, in alcohol, collected in Guangdong Province, Xinyi County, town of Dacheng, Dawuling Nature Reserve , stream inside entrance of Reserve , 111.19° E, 22.27° N, 1021 m, 26 May 2004, Xin Zhou and Sanbao Tang leg. ( NJAU).

Description

Male

BODY. Length of each forewing: 1.0 mm (n = 1). Body (in alcohol) dark brown. Head dark brown; eyes black; antennae dark brown, palpi brown. Thorax dark brown dorsally, brown laterally and ventrally; legs brown; wings brown. Abdomen dark brown dorsally and brown ventrally.

MALE GENITALIA ( Fig. 1 A–D). Segment IX (IX) in lateral view with each anterior margin straight, each posterior margin sinuate, dorsal margins short and ventral margins long ( Fig. 1A ); in dorsal view anterior margin straight, and posterior margin with deep U-shaped incision ( Fig. 1B ). Preanal appendages and apicodorsal lobe of segment IX fused tightly into complex (com.), in lateral view complex somewhat trapezoidal with upper margin 3 times as long as the lower margin ( Fig. 1A ), and in dorsal view somewhat tongue-shaped, tapering from base to apex ( Fig. 1B ). Anal sclerites (as., Fig. 1A ) in lateral view barshaped, about ½ times as long as upper margin of complex. Apical band (ab.) in lateral view slender, slightly curved posteriad ( Fig. 1A ). Tergal band (tb.) membranous, in lateral view elongate. Phallotheca (pht.) irregular in lateral view, somewhat rectangular in ventral view; aedeagus (aed.) with a large base, then progressively narrowed to rounded apex; paired parameres (par.) slender and shorter than aedeagus. Basal segments of inferior appendages (bia.) setose sparsely, each is subrectangular in lateral view and triangular in ventral view; apical segments (aia.) setose densely, each divided into 2 lobes, each upper lobe slightly shorter than lower one.

Female

Unknown.

Distribution

China (Guangdong).

Figures

Fig. 1. Rhyacophila linguiformis sp. nov., male genitalia. A. Lateral view. B. Dorsal view. C. Ventral view. D. Complex of preanal appendages and apicodorsal lobe of segment IX, caudal view. Scale bar: 0.5 mm.