Despaxia asiatica, Zwick, 2010

Zwick, Peter, 2010, New Species And New Records Of Plecoptera From Korea And The Russian Far East, Illiesia 6 (9), pp. 75-97 : 90-92

Despaxia asiatica sp. n.

(Figs. 44-46)

Material examined. REPUBLIC OF KOREA: ♂ holotype, Gangwondo , Pyeongchang , YongpyeongMyeon , Nodong-li, Nodong valley, Alt. 900 m ,1.X.-

11.XI. 2006, 37°42.08'N 128°28.89'E, 3 Malaise traps in forest in shade.

Adult habitus. A typical dark leuctrid with strongly infuscate wings. FWL 6.5 mm. The male abdominal tip distinguishes it from other members of the family and evidences its membership in genus Despaxia .

Male. Tergites 3-9 with black, strongly sclerotized antecosta, remainder lightly sclerotized. Anterior tergites possess 4 indistinct darker spots in a transverse row. T9 caudally deeply excised, medially remains no more than the very strong antecosta. Laterally the antecosta divides to form the sclerotized anterior and posterior edges of the lateral portion of the segment. T10 is medially no more than a narrow sclerite to which the cerci and the epiproct are attached (Fig. 44). The epiproct is a transverse finely pilose sclerite with short stalk. Cerci straight, with small ventrocaudal notch, the wart-like second segment is located on top of the lobe, beneath the notch. Middle of S9 caudally arched, forming a slightly projecting subgenital plate with some long setae. Laterally (Fig. 46) the subgenital plate is demarcated by short folds originating in narrow caudo-lateral notches. No ventral lobe. Middle of segment 10 medially occupied by the wide paraprocts. In ventral view (Fig. 45) they form two paramedian weekly sclerotized triangles concealing the bases of the strongly outwardly curved specilla whose inner tube is faintly visible by transparency. More caudally the specilla converge again, their ends lie parallel to each other. The specilla enclose an approximately heart-shaped open space between them. The specillum tip is pointed, with a faint subterminal swelling. In dorso-caudal view the curved sperm tubes inside the paraprocts are seen to turn towards the midline but remain narrowly separated. Anteriorly from the outwardly curved base of specillum the lateral part of paraproct forms a simple flat plate. In lateral view the specilla curve away from the body and are distally straight. Near the base appears a little swelling over the sperm duct.

Female. Unknown.

Diagnosis. The only other species in the genus is the west-Nearctic D. augusta (Banks) which was compared. The general similarity of the two species is striking, compare Figs. 44-46 to figures 3 and 4 of Kondratieff & Lechleitner (2002). However, the basally divergent and widely separate specilla formed by the inner paraproct lobes distinguish the new species immediately from D. augusta where the same lobes are parallel and lie close together over their entire length. D. augusta has an unsclerotized ventrocaudal edge of cercus carrying the rudimentary 2 nd segment but there is no notch. In D. augusta , the antecosta of T8 is medially distinctly recessed, and the epiproct has a faint midline.

Notes. The flight period is apparently autumnal, same as in the American relative ( Kondratieff & Lechleitner 2002).

Etymology. The discovery of the new species provides yet another example of genera shared between the Palearctic Far East and Western North America. In the Leuctridae , Megaleuctra , Perlomyia , and Paraleuctra share the same general distribution. The specific name refers to the range of the new species and emphasizes the transoceanic disjunction from D. augusta .