Jankowskia Oberthür, 1884

Jiang, Nan, Xue, Dayong & Han, Hongxiang, 2010, A review of Jankowskia Oberthür, 1884, with descriptions of four new species (Lepidoptera: Geometridae, Ennominae), Zootaxa 2559, pp. 1-16 : 2-3

Jankowskia Oberthür, 1884

Jankowskia Oberthür, 1884 , Études ent., 9: 25. Type species: Jankowskia athleta Oberthür, 1884 , by subsequent designation by Fletcher, 1979.

Pleogynopteryx Djakonov, 1926 , Jahrb. Martj. Staatsmus. Minussinsk, 4: 66, 70. Type species: Pleogynopteryx tenebricosa Djakonov, 1926 (= Boarmia bituminaria Lederer, 1853 ), by original designation.

Description. Head: Antenna greyish brown mixed with white scales dorsally, bipectinate in male, simple filiform at tip and in female. Frons blackish brown or greyish brown, smooth-scaled. Labial palpus blackish brown or greyish brown, short and stout, extending slightly beyond frons. Vertex greyish brown or blackish brown.

Thorax: Patagium and tegula blackish brown, suffused with grey scales. Dorsal side blackish brown, greyish black or greyish brown. Legs blackish brown mixed with yellow. Hind tibia with two pairs of spurs in both sexes, dilated, with or without hair-pencil in male. Wings blackish brown or grey, diffused with blackish grey small dots. Forewing with apex and anal angle rounded, outer margin almost straight or weakly protruded, anal margin straight. Hindwing rounded, with costa and anal margin straight, outer margin slightly wavy. Patterns of forewing: costa yellowish brown, diffused with short longitudinal greyish brown flecks; antemedial, medial, and postmedial lines forming three black patches on costa; antemedial line black, slightly wavy, distinct, protruded inwards below cell, then protruded outwards, extending to the wing base near anal margin; medial line black, distinct or indistinct; postmedial line black, wavy, distinct, protruded outwards between M1 and M2, protruded inwards below M2, then paralleling to medial line; a yellowish brown patch outside postmedial line, a dull brown shadow in the middle of the patch; submarginal line greyish black, indistinct; terminal line black, appearing as series of small crenulate patches between veins; fringes greyish brown mixed with blackish brown; discal spot black, present as a strip or small dot, distinct or indistinct. Hindwing with basal area greyish brown, blackish brown or greyish black; medial line black, straight, distinct or indistinct, the width various between species; postmedial line black, distinct, wavy. Underside dull grey, greyish black or greyish white, transverse lines pale brown, a faint broad band usually present outside postmedial line, costa of forewing pale yellow or greyish yellow, diffused with fewer flecks, medial and postmedial lines often forming two black patches on costa of forewing.

Venation: Frenulum developed. Forewing: male with a fovea between anal fold and 2A; R1 and R2 separate, almost parallel or shortly stalked, diverging before anterior angle of cell in male, anastomosing in female; R3+4 and R5 longly stalked; R3–5 diverging from or before anterior angle of cell in male, always diverging before anterior angle in female; M1 diverging from anterior angle of cell, not stalked with R3–5; M3 diverging from posterior angle of cell; CuA1 diverging before posterior angle of cell. Hindwing: Sc+R1 close to cell less than 1/2 length of cell; Rs diverging before anterior angle of cell; M1 diverging from anterior angle of cell, M2 absent, M3 and CuA1 from posterior angle; 3A absent.

Abdomen: First abdominal segment with pale grey dorsal band, remaining segments blackish brown or greyish brown. Sternite 3 of male abdomen without setal patch.

Male genitalia: Uncus triangular, length equal to basal width. Tegumen with or without a pair of posterior processes, its length varying, with or without (maybe lost during preparation) a bundle of long setae apically. Gnathos connected at middle, with median process small, the shape and the ratio of its length to the basal width various. Valva terminally blunt, bearing a large area of long setae; one or two clusters of long setae near center; ventral margin of valva sometimes protruded outwards at middle. Costa almost straight. Saccus small, rounded. Juxta symmetrical in J. athleta , J. pseudathleta and J. improjecta , or asymmetrical with an apical process at the left side in other members of the genus, the shape, length and degree of sclerotization of the processes various. Aedeagus short and stout, weakly sclerotized. Vesica with cornuti shaped as a bundle of spines.

Female genitalia: Ovipositor heavy elongated. Apophyses posteriores much longer than apophyses anteriores. Sterigma with central part almost rounded or quadrate, with a pair of sclerotized lateral lobes. Ductus bursae weakly or strongly sclerotized, wrinkled. Corpus bursae oval or round, membranous, bearing an almost flat signum with marginal spines, the shape of signum various.

Diagnosis. On the wing patterns, the genus Jankowskia resembles Phthonosema Warren, 1894 in the postmedial line usually protruded outwards between M1 and M2, protruded inwards below M2, then paralleling to the medial line. But Jankowskia differs from Phthonosema in having a yellowish brown patch outside the postmedial line on forewing; in the male genitalia, Jankowskia has a fairly simple valva, while in Phthonosema the sacculus is separated from the valva.

Distribution. China, Russia (South Siberia and South of Far East), Mongolia, Japan, North Korea, South Korea, Thailand.

Biological notes. Adult are mostly active at night. Most specimens from China have been recorded from 230 m to 2400 m elevation beteween June and October. The pupa was described in Nakamura and Masanao (2004) and Sato (1984). The larva were described and illustrated in Sato (1984). Larval host plants ( Sato & Nakajima, 1975; Nakajima, 1975; Sato, 1976; Sato, 1980; Sato, 1984; Scoble, 1999) have been recorded from the families Aquifoliaceae , Fagaceae , Lauraceae , Rosaceae , Salicaceae , Theaceae .

Remarks. Sato (1980) stated in his description of the genus Jankowskia that the tegumen possesses a pair of posterior processes in the male genitalia. Later, Kim et al. (2001) considered Pleogynopteryx as a generic synonym of Jankowskia although J. bituminaria lacks the tegumen posterior processes. Herein, the length of tegumen posterior processes of the four new species is varying from almost absent without long setae apically (in J. obtusangula ) to short, triangular with or without a bundle of long setae apically ( J. curva , J. acuta and J. improjecta ). So, these new species could be a series of transitional forms between J. bituminaria and other species of Jankowskia , and support the synonymization of Pleogynopteryx to Jankowskia .