Psilotreta flavida, Kawase, 2021

Kawase, Naoki, 2021, Description of three new species of Psilotreta (Trichoptera: Odontoceridae) from Japan, Zootaxa 4980 (3), pp. 589-598 : 595-597

Psilotreta flavida sp. nov.

( Figs 4A–4K )

Diagnosis. This new species is somewhat similar to P. voluta sp. nov. and P. moritai sp. nov. described in this study but can be distinguished from them by a character of the male genitalia. In P. flavida , each lateral process of segment X has a ventral projection directed posterad instead of anteroventrad as in P. voluta and P. moritai .

Adult Male ( Figs 4A–4C ). General coloration yellowish to pale brown in body, antennae and wings. Maxillary palps approximately same as for P. voluta sp. nov. Head in dorsal view similar to that of P. voluta , but notch between anteromesal warts deeper than for P. voluta ( Fig. 4A ). Length of each forewing: male 6.6–7.3 mm (mean = 7.1 ± 0.19, n = 22), female 6.8–8.1 mm (mean = 7.5 ± 0.45, n = 7). Venation similar to P. voluta sp. nov. and P. moritai sp. nov., but cross-vein between M3+4 and Cu1 present in male hind wings ( Fig. 4C ).

Male Genitalia ( Figs 4D–4I ). Tergum IX subtriangular in dorsal view, with steep sides above rounded basal setal warts. Basal segment of each inferior appendage long, extending beyond posterior margin of lateral process, cylindrical and covered with setae, slightly tapered; apical segment about 1/4 length of basal segment, cylindrical, with many brown teeth on apical half. Preanal appendages broad at basal 3/4 and abruptly tapered distally in lateral view, not extending beyond posterior apex of median dorsal process. Segment X with median dorsal process narrow subapically, slightly clavate, sparsely setose apically; lateral processes each with acute ventral projection apically directed caudad and upcurved; each intermediate appendage heavily sclerotized, sharply curved posteroventrad, usually forming C shape in lateral view, positioned on lower 2/3 of lateral process with its top never reaching dorsal margin of lateral process.

Phallus with phallotheca short, cylindrical; endotheca with pair of short and broad parameres located lateroventrally, about 2 times as long as its basal width; aedeagus slightly depressed dorsally in lateral view, with ventral plate weakly sclerotized, membranous apex nearly rounded with posterior margin slightly notched in ventral view, internal phallotremal sclerite distinct, V-shaped in ventral view, strongly C-shaped in lateral view.

Female Genitalia ( Figs. 4J–4K ). Vaginal chamber almost 2 times as long as sternum IX in ventral view; posterior vaginal sclerites heavily sclerotized apically.

Larva, Pupa. Unknown.

Holotype. male, Japan, Shikoku, Ehime, Uchiko-cho, Odamiyama ( Namakusa valley ), 33°32’N, 132°50’E, alt. 1200 m, 26.vii.1998, E. Yamamoto [Eiji Yamamoto] ( LBM141001212 ).

Paratypes. Japan, Shikoku , Ehime : 18 males and 5 females, same locality as holotype, 8.viii.2000, E. Yamamoto. ( LBM141001213–141001235 ) ; 1 male, same locality as holotype, 28.vii.2000, E. Yamamoto ( CBM0180208 ) ; 2 males, same locality as holotype, 9.viii.2016, E. Yamamoto ( CBM0180209–0180210 ) ; 1 male, Oozu-shi, Hijikawa-cho, Yamatosaka , 33°28’N, 132°43’E, 7–9.viii.2000, Tsukaguchi ( MKNC2021020 ) ; 1 male, Kumakogen-cho, Yurano , 33°38’N, 132°53E, 10.vii.2007, E. Yamamoto ( MKNC2021021 ) ; 1 male, ibid, 20.vii.2007, E. Yamamoto ( MKNC2021022 ) ; 1 male, ibid, 31.vii.2007, E. Yamamoto ( MKNC2021023 ) . Kochi: 4 males, Niyodogawa-cho, Ooue ( Mt.Torigata ), 33°27’N, 133°04’E, 25.vii.2001, N. Kawase ( MKNC2021024–2021027 ) ; 2 males, Ino-cho, Teragawa ( Yosakoi pass), 33°45'N, 133°11'E, 3.viii.2001, I. Yamashita ( MKNC2021028–2021029 ) ; 1 male, Kamishi, Monobe-cho, Kubokage ( Nishikuma valley ), 33°47'N, 133°58'E, 5.viii.2006, I. Yamashita ( MKNC2021030 ) ; 1 male, ibid, 26.viii.2006, I. Yamashita ( MKNC2021031 ) ; 1 male, Kochi-shi, Tosayama-Takakawa ( Mt. Kuishi ), 33°40’N, 133°30’E, 8.vi.2005, M. Takai ( MKNC2021032 ) ; 2 males, Tosashimizu-shi, Kaikake , 32°51’N, 132°54’E, 28.vi.2003, M.Takai ( MKNC2021033–2021034 ) ; 3 males and 2 females, ibid, 26.vi.2004 ( CBM0180211–0180215 ) ; 1 male, Sukumo-shi, Yamana-cho, Ittyubara , 33°00’N, 132°48’E, 15.vi.2001, M. Takai ( MKNC2021035 ) .

Etymology. The Latin specific epithet flavida , “yellow” in English, refers to the yellowish general coloration of this new species.

Distribution. Shikoku.

Habitat and Biology. Adults were collected near streams in mountain forests from June (alt. about 100 m on Sukumo-shi and Tosashimizu-shi) to August (alt. about 1000 m in Uchiko-cho) by a light trap or Malaise trap.

Japanese Name. Kiiro-kiso-tobikera

Figures

FIGURE 4. Psilotreta flavida sp. nov. 4A, male head, dorsal; 4B, same, left lateral; 4C, male right wings, dorsal; 4D–4I, male genitalia: 4D, left lateral; 4E, left lateral process & intermediate appendage of segment X, left lateral; 4F, phallus, left lateral; 4G, phallus, ventral; 4H, dorsal; 4I, ventral. 4I–4J, female genitalia: 4J, dorsal; 4K, ventral.Abbreviations: aed. = aedeagus; avs. = anterior vaginal sclerite; end. = endotheca; int.app. = intermediate appendage (paired); lat.pr. = lateral process (paired); par. = paramere (paired); phall. = phallotheca; pvs. = posterior vaginal sclerite; sIX = sternum IX; v.pr. = ventral projection (paired).