Pseudostenophylax dentilus (Kobayashi 1973)

Nozaki, Takao, 2013, The genus Pseudostenophylax Martynov (Trichoptera, Limnephilidae) in Japan, Zootaxa 3666 (4), pp. 559-578: 566-568

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Pseudostenophylax dentilus (Kobayashi 1973)


Pseudostenophylax dentilus (Kobayashi 1973) 

( Figs. 4View FIGURES 4 – 5. 4, 10View FIGURE 10)

Stenophylax dentilus Kobayashi 1973  , 38– 39, pl. 10, male, female.

Pseudostenophylax dentilus: Nozaki et al. 2000  , 205, changed combination. Pseudostenophylax ondakensis: Schmid 1991  , 23– 24, pl. 2, male, misidentification.

Adult. General appearance similar to P. tochigiensis  . Forewings each 15–18 mm long in male, 14–16 mm in female.

Male genitalia. Tergum VIII higher than long in lateral aspect; posterodorsal sclerotized area densely covered by short spine-like setae, stepwise in lateral and dorsal aspect, with apical concavity in dorsal aspect. Segment IX in lateral aspect short dorsally, swelling posterolaterally at midheight. Superior appendages ear-like in lateral aspect, slightly concave mesally. Intermediate appendages similar to those of P. ondakensis  , but approximately as long as wide; hatchet-shaped in dorsal aspect; directed inward, upper side slightly concave, covered with minute denticles except for basolateral part. Lateral sclerites of segment X largely fused with intermediate appendages. Inferior appendages one-segmented, triangular in lateral aspect, round in ventral aspect, rugged apically. Aedeagus bottle-shaped in dorsal aspect, with long neck and bulbous base; mostly sclerotized but weak at base. Parameres large, membranous basally, sclerotized apically; sclerotized part hammer-shaped, denticulate apically, mesal slender part with several long spines apically.

Female genitalia. Shape of segment X similar to that of P. ondakensis  ; but each lobe slender, 1.5 times as long as basal width in dorsal aspect, with dorsal ridge near mesal margin in dorsal aspect. Vaginal sclerite similar to that of P. tochigiensis  , concavity of dorsoposterior corner shallow in lateral aspect.

Final instar larva. Larva up to 18 mm. Head mostly reddish brown, round in dorsal aspect; primary setae 5 each about 0.7–1.0 times as long as distance between bases of setae 5; setae 6 transparent, short, each about 1 / 2 length of seta 5; setae 14 longest; ventral setae 18 minute. Ventral apotome, labrum and mandibles similar to those of P. ondakensis  . Prosternal horn long. Pronotal sclerites dark brown; with long pigmented or short transparent setae broadly on setal areas from sa 2 to sa 3, but without setae in anteromesal area except along anterior margin; long pigmented and short transparent setae arising alternately along anterior margin, anterior edge with transparent hair-like setae. Mesonotal sclerite yellowish to dark brown. Metanotal sclerites yellowish to dark brown, with transverse band of setae between sa 2 sclerites. Hind femora each with 5 to 7 setae along ventral edge, with 9 to 16 setae laterally. Abdominal segment I with 80 to 100 setae dorsally, with more than 100 setae ventrally. Abdominal gills single, present on following segments: dorsal gills on II to V (anterior and posterior), on VI (anterior and often posterior) and usually on VII (anterior); lateral gills on II to IV (anterior and posterior), often on V (anterior and posterior) and VI (posterior); ventral gills on II to VII (anterior and posterior). Lateral fringe and forked lamellae present on abdominal segments III to VIII. Ventral chloride epithelia present on abdominal segments II to VII. Anal claws each with one accessory hook.

Case. Both larval and pupal cases similar to those of P. tochigiensis  .

Specimens examined. Shenjogahara, Chokai National Park, Yamagata, 11 males, 7 females (in alcohol, including the type series materials but not separated) (CBM, M- 2495).

Other specimens. Miyagi: small tributary of Yoko-kawa, 850 m a.s.l., near Funagata-yama, Aoba-ku, Sendaishi, 5.x. 2005, T. Nozaki, 4 larvae (TN); ibid., larvae collected on 5.x. 2005, adults emerged on 29.iv – 2002 by T. Nozaki, 2 males, 2 female (TN); Ya m a ga ta: Shizu, Nishikawa-machi, 19.ix. 2004, H. Nishimoto, 18 larvae (2 larvae NMNH; others TN); ibid., 13.ix. 2008, N. Kuhara, 1 larva (TN); Gassan springs, 775 m a.s.l., Shiga, Nishikawa-machi, 24.ix. 2004, H. Moriya, 2 larvae (TN): ibid., larvae collected on 24.ix. 2004 by H. Moriya, adults emerged on 27.iv – 2005 by T. Nozaki, 3 males (1 male NMNH; others TN); Tateki, Asahi-machi, 12.ix. 2008, N. Kuhara, 1 male (TN); Yanagisawa-goya, Kurobushi-kogen, Higashine-shi, 12.ix. 2008, N. Kuhara, 2 males (TN); Fukushima: Kowashimizu, Takamori-atami, Koriyama-shi, 16.v. 1988, S. Ishiwata, 1 larva (TN); Gunma: Yamanohana, Oze, 26.ix. 1995 (light), K. Tanida & T. Nozaki, 1 male (TN); stream flowing into Lake Suga-numa, Katashina-mura, 27.v. 1986, S. Ishiwata, 7 larvae (TN); Niigata: Nabekura-zawa, tributary of Tainai-gawa, 330 m a.s.l., Tainai-shi, 19.ix. 2004 (light), N. Kuhara, 2 males (TN); Aburuma-gawa, Irihirose, Uonuma-shi, 10.x. 1993, S. Ishiwata, 1 male (TN); Shiori-toge, 1,000 m a.s.l., Yunotani, Uonuma-shi, 2.vii. 1999, T. Hattori, 1 male (CBM- 146879); Fukamichi-zawa, Hirogami, Uonuma-shi, 7.ix. 2000, N. Kawase, 1 larva (TN); Shimizu, Shiozawa, Minamiuonuma-shi, 5.ix. 2001 (light), N. Kawase, 1 male (TN); Kiyotsu-kyo, Kaikake, Yuzawa-machi, 11– 14.v. 1999, N. Kawase, 4 larvae (NK); Nagano: Togakushi, 5.viii. 1957, K. Fujimoto, 1 male (NMNH, Nakahara collection).

Distribution. Japan (Honshu).

Biology. Similar to that of P. ondakensis  .

Japanese name. Yamagata-miyama-tobikera.

Remarks. Kobayashi (1973) said that he designated a male collected from Shenjogahara, Chokai National Park, Yamagata Prefecture on May 26, 1969, as the holotype (M. 2495 a) and five males collected from the same locality on the same day as paratypes (M. 2495 b –f). He also determined 4 males (M. 2495g –j) and 8 females (M. 2495 k –r) collected from Mt. Azuma, Yamagata Prefecture on May 26, 1469 [! 1969] as this species in the same paper. In the Kobayashi collection now deposited in CBM, I found 11 males and 7 females in a vial labeled “Limnephili 2495 Ƥ ”. Although the holotype or paratypes were not separated in the vial, all males agreed with the description by Kobayashi (1973). I also examined the male determined as P. ondakensis  by Schmid (1991), and confirmed it to be the same species as this species.

The male of this species is similar to that of P. ondakensis  , but easily distinguishable by the shape of the posterodorsal area of segment VIII and the phallus. The larva of this species is also similar to that of P. ondakensis  and only distinguishable from that of the latter by the shape of the head dorsally: The head of this species is without a depression along the frontoclypeal suture, but that of P. ondakensis  has a depression.