Pseudostenophylax tohokuensis , Nozaki, Takao, 2013

Nozaki, Takao, 2013, The genus Pseudostenophylax Martynov (Trichoptera, Limnephilidae) in Japan, Zootaxa 3666 (4), pp. 559-578: 569

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Pseudostenophylax tohokuensis

sp. nov.

Pseudostenophylax tohokuensis  sp. nov.

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

Diagnosis. This species belongs to the P. ondakensis  Species Group (Schmid 1991). The male of this species can be distinguished from those of the other Japanese species by the following unique characters: Intermediate appendages are each shaped as a parallelogram in dorsal aspect, and apices of parameres are round posteriorly and serrate mesally with a few long spines. The larva of this species is similar to those of P. k u h a r a i sp. nov. and P. itoae  sp. nov. in having ventral chloride epithelia on abdominal segments II to VII and a pale marking on the posterior corner of the frontoclypeal apotome of the head, but is distinguishable from these latter species by the length of primary setae no. 5 on their head: Larvae of this species bear short transparent primary setae 5 which are less than half as long as the distance between bases of setae 5, but larvae of the latter 2 species have setae 5 that are longer than the distance between their bases.

Adult. Only 2 males and 4 females reared from larvae available for this study. General appearance similar to above 3 species, but ocelli not so large. Forewings 11–13 mm long in male, 10–11 mm in female.

Male genitalia. Tergum VIII slightly higher than long in lateral aspect; posterodorsal sclerotized area densely covered by short spine-like setae, similar to that of P. ondakensis  , but covering slightly greater area posteriorly. Segment IX in lateral aspect short dorsally, concave posteriorly and swelling posterolaterally at midheight. Superior appendages ear-like in lateral aspect, slightly concave mesally. Intermediate appendages each shaped as rounded parallelogram in dorsal aspect; upper side covered with minute denticles, deeply concave; ventral part protruding posteriorly. Lateral sclerites of segment X large, fused into intermediate appendages, protruding posterolaterally. Inferior appendages each one-segmented, triangular in lateral aspect, trapezoidal in ventral aspect. Aedeagus bottle-shaped in dorsal aspect, with long neck and bulbous base; similar to that of P. dentilus  , but sclerotized base broader than that of P. dentilus  . Parameres large, membranous basally, sclererotized apically; each having sclerotized area covered with minute denticles apically; apex round posteriorly, serrate mesally, with few long spines.

Female genitalia. Very similar to those of P. dentilus  and indistinguishable from them.

Final instar larva. Larva up to 18 mm long. Head mostly reddish brown, but posterior corner of frontoclypeal apotome yellowish brown; round in dorsal aspect; primary setae 5 transparent, short, less than half length of distance between bases of setae 5; setae 6 transparent, short, each slightly shorter than setae 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 to dark brown; with long pigmented or short transparent setae broadly distributed on setal areas from sa 2 to sa 3, but setae sparse in anteromesal area; long pigmented setae 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 6 to 7 long setae along ventral edge, with 8 to 15 setae laterally. Abdominal segment I with 60 to 100 setae dorsally, with more than 100 setae ventrally. Abdominal gills single, present on following segments: dorsal gills on abdominal segments II to V (anterior and posterior) and on VI (anterior), and often on VII (anterior); lateral gills on II to IV (anterior and 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  .

Holotype. Male (pinned), tributary of Ohtaki-gawa, Kanohara, Kami-cho, Miyagi, 38 ° 32 ’N, 140 ° 39 ’E, 450 m a.s.l., larva collected on 6.x. 2001, adult emerged on 26.iii. 2002 by T. Nozaki (CBM- 146872).

Paratype. Same data as the holotype except for emergence date of 6.iv. 2002, 1 male (in alcohol) (TN).

Other specimens examined. Miyagi: Same locality as the holotype, 6.x. 2001, T. Nozaki, 4 larvae (TN); same data as the holotype except for emerging date as 26.iii– 14.iv. 2002, 4 females (1 female: CBM- 146880; others: TN).

Etymology. Specific name refers to the name of the region where this species was collected.

Distribution. Japan (Honshu).

Biology. Larvae were collected from a small mountain flow.

Japanese name. Tohoku-miyama-tobikera.