Pseudostenophylax itoae , Nozaki, Takao, 2013

Nozaki, Takao, 2013, The genus Pseudostenophylax Martynov (Trichoptera, Limnephilidae) in Japan, Zootaxa 3666 (4), pp. 559-578: 571-573

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Pseudostenophylax itoae

sp. nov.

Pseudostenophylax itoae  sp. nov.

( Figs. 7View FIGURES 6 – 7. 6, 10View FIGURE 10)

Pseudostenophylax  sp. 1: Kuhara 2011, 53, 74.

Diagnosis. This species belongs to the P. ondakensis  Species Group (Schmid 1991). Both adults and larvae are very similar to those of P. kuharai  sp. nov., but are distinguishable from the those of the latter by the characters given in the diagnosis for that species.

Adult. General appearance similar to P. ondakensis  . Forewings 13–16 mm long in male, 9–11 mm in female.

Male genitalia. Tergum VIII higher than long in lateral aspect; posterodorsal sclerotized area densely covered by short spine-like setae, rounded square with slightly wider posterior margin in dorsal aspect, with central depression on posterior half. Segment IX in lateral aspect short dorsally, concave posteriorly and swelling posterolaterally at midheight. Superior appendages with dorsal globular lobe in lateral aspect. Intermediate appendages rectangular in dorsal aspect, slightly longer than wide, V-shaped in caudal aspect; symmetrical dark pigmented areas normal and reverse L-shaped in dorsal aspect, covered with minute denticles. Lateral sclerites of segment X largely fused with intermediate appendages. Inferior appendages each one-segmented, triangular in lateral aspect; trapezoidal in ventral aspect, but posterior margin variable. Phallicata bottle-shaped in dorsal aspect, with long neck and bulbous base; mostly sclerotized. Parameres similar to those of P. kuharai  , but both projections shorter than those of latter, occasionally hook-like, covered with minute denticles; each with mesal part broader, with several long spines apicomesally.

Female genitalia. Very similar to those of P. dentilus  .

Final instar larva. Larva up to 19 mm long. Head mostly reddish brown, but posterior corner of frontoclypeal apotome yellowish brown; round in dorsal aspect; primary setae 5 relatively long, each about 1.2 times distance between bases of setae 5; setae 6 transparent, short, each about half 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 yellowish brown, bearing long pigmented and short semitransparent setae; anterior edge with transparent hair-like setae. Mesonotal sclerites yellowish brown. Metanotal sclerites yellowish brown, with 7–12 setae between sa 2 sclerites. Hind femora each bearing 5–7 setae along ventral edge, with 6–9 setae laterally. Abdominal segment I with 60 to 80 setae dorsally, with more than 100 setae ventrally. Abdominal gills single, present on following segments: Dorsal gills on abdominal segments II to III (anterior and posterior), on IV (anterior and often posterior), on V (anterior) and often on VI (anterior); lateral gills on II (posterior) and on III (anterior and posterior); ventral gills on II to VII (anterior and posterior). Lateral fringe present on posterior part of abdominal segment II to VIII.

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  .

Holotype. Male (pinned), head waters, Izari-gawa, Eniwa-shi, Ishikari, Hokkaido, 42 ° 48 ’ 54 ”N, 141 ° 16 ’4.8” E, 23.viii. 2009, N. Kuhara (light) (CBM- 146874).

Paratypes. Izari-gawa, 205 m a. sl., Eniwa-shi, Ishikari, Hokkaido (42 ° 51 ’ 29 ”N, 141 ° 23 ’ 21 ”), 21.viii. 2008, T. Ito (light), 3 males (in alcohol) (2 males: NMNH, 1 male: TN).

Other specimens examined. Hokkaido: Rarumanai-gawa, 700 m a.s.l., Eniwa-shi, 11–21.viii. 2004 (Malaise trap), T. Ito, 4 males, 1 females (TN); a tributary of Rarumanai-gawa, 700 m a.s.l., Eniwa-shi, 13.vii. 2002, T. Ito, 4 larvae (TN); ibid., larvae collected on 13.vii. 2002, adults emerged on 23–29.viii. 2002 by T. Ito, 3 females (TN); Otarunai R., 450 m a.s.l., Sapporo-shi, 1992 (light), N. Kuhara, 1 male (TN); small stream, 450 m a.s.l., Bifue, Chitose-shi, 17.v– 5.ix. 2009 (Malaise trap), N. Kuhara, 17 males, 1 female (TN); small stream, Bifue-notaki, Bifue-gawa, Chitose-shi, 27.viii. 2001, T. Ito, 1 larva (TN); small stream, Orofure-toge, 810 m a.s.l., Sobetsucho, 11– 2011 (Malaise trap), N. Kuhara, 3 males (TN); spring stream beside Shiribetsu-gawa, Aichi, Otakiku, Date-shi, 2011 (Malaise trap), N. Kuhara, 5 males (TN).

Etymology. This species is dedicated to Dr. Tomiko Ito, Hokakido Aquatic Biology, who gifted me many valuable specimens, including this species.

Distribution. Japan (Hokkaido).

Biology. Larvae were collected from small mountain streams. Adults were collected from early summer to autumn (Kuhara 2011).

Japanese name. Ito-miyama-tobikera.