Libnotes (Afrolimonia) plutonis Alexander 1924

Libnotes (Afrolimonia) plutonis (Alexander, 1924)

Limonia plutonis Alexander, 1924: 552 –553;

Limonia (Limonia) plutonis Alexander, 1953: 157;

Libnotes (Afrolimonia) plutonis Savchenko, Krivolutskaya, 1976: 120 –123; Savchenko, 1983: 115; 1985: 43; 1989: 326.

General body coloration semi-polished black, covered with sparse gray pruinosity. Male body length about 9.0 mm, that of female 9.45 mm, wing length of male 12.10 mm, that of female 12.36 mm.

Head black, covered with gray pruinosity, which is more intense at eye margins, and semi-erect dark brown setae. Anterior vertex very narrow, silvery gray. Eyes large, nearly reaching each other dorsally and ventrally. Antenna 1.97 mm long in female, 14-segmented. Scape long, nearly cylindrical, reaching to about tip of rostrum, dark brown, covered with sparse gray pruinosity. Pedicel short, slightly widened distally, dark reddish brown, cowered with few setae. Basal flagellomere short, nearly rounded, succeeding segments getting elongate towards apex. Flagellum uniformly black. Longest verticils up to three times as long as respective segments. Short pubescence, covering segments whitish. Rostrum dark brown, nearly black. Palpus black, covered with erect dark brown setae. Two basal segments wide, both distal segments distinctly narrower. Labella dark brown.

Thorax black, covered with gray pruinosity. Cervical sclerites, pronotum and mesonotal prescutum semipolished. Prescutum with four polished confluent black stripes, just lateral margin and area surrounding pseudosutural fovea gray, because of denser pruinosity. Central stripes narrowly separated by gray line only frontally. Scutal lobes, scutellum and mediotergite dark brown, nearly black, semi-polished, covered with brownish-gray pruinosity. Pleuron uniformly dark brown to black, semi-polished, covered with gray pruinosity. Katepisternum with three long yellowish setae. Wing (Fig. 1) with brownish tinge. Stigma large, elongate and dark brown. Costal area yellowish. Dark areas surround cord, distal end of discal cell, cubital vein and at distal wing margin. Whole posterior margin narrowly darkened. Veins brown. Venation: Sc1 not reaching branching point of Rs, Sc2 some distance before Sc1 tip. Rs slightly arched at base. Both branches of Rs long, parallel to each other and slightly turned backwards before wing margin. Vein R2 about 1.5 its own length before R1 tip. Cross-vein r-m distinct, at base of discal cell. Discal cell elongate, 2.5 times as long as wide. Basal deflection of CuA1 slightly beyond branching point of M. A1 nearly straight, A2 slightly arched before wing margin. Anal angle medium-sized, posterior margin widely rounded. Length of male halter 1.85 mm, that of female 1.75 mm. Stem of halter pale, base brownish yellow, knob blackish distally. Coxae dark brown, just fore coxa dorsally black. Trochanter brownish yellow, distal margin narrowly blackened. Femur widely brownish yellow at base, turning black towards distal end. Tibia and tarsus dark brown, two distal tarsomeres black. Male femur I: 7.75 mm long, II: 8.20 mm; tibiae I: 9.80 mm, II: 8.65 mm; tarsus I: 9.90 mm, II: 8.10 mm long. Female femur II: 8.10 mm, III: 8.80 mm; tibiae II: 8.70 mm, III: 9.80 mm long. Claw polished-black with single subbasal spine.

Abdomen dark brown, semi-polished, covered with sparse pruinosity. Distal part of tergites and sternites blackened, distal margin narrowly gray. Tergites and sternites covered with fine yellowish setae. Male genitalia same color as abdomen. Male ninth tergite simple, posterior margin with small median emargination (Fig. 2). Gonocoxite slightly elongate, with elongate setose ventro-mesal lobe. Outer gonostylus narrow, sclerotized, arched distally, tip acute. Inner gonostylus nearly rounded, comparatively short, twice as short as gonocoxite, fleshy and setose. Rostral prolongation wide at base, turning narrow distally, slightly arched, bearing tubercle at about onethird, that is armed with two pale arched spines (one of studied males from Japan has two spines on one side and three on the other). Another elongate lobe starts at about middle of gonostylus, apex armed with 2–3 long setae, that are at the right angle to the lobe itself, setae distinctly protrude beyond posterior margin of gonostylus. Paramere triangle-shaped at base, distal part distinctly narrowed, finger-shaped. Penis simple, elongate, apex sharply widened. Ovipositor (Fig. 3) with black tenth tergite and base of hypogynial valve. Cercus and distal part of hypogynial valve polished brown. Cercus with slightly raised distal part and bearing subapical bump on dorsal margin. Hypogynial valve long, reaching or nearly reaching tip of cercus.

Elevation range. Both specimens were collected at about 450–500 m altitude in Korea. Species was registered at altitudes from 1400 to nearly 2000 m in Japan (Alexander, 1953).

Period of activity. The two adults were collected at the beginning of July.

Habitat. Dense mixed groves on mountainous river slopes. This species was actively flying to light during our night collectings.

General distribution. This species was previously known only from Sakhalin, Kuril and Japanese islands. This is the first record not only from Korea, but from the Asian continent.

Examined material: male (pinned), S. Korea, Jeollanam-do, Gurye-gun, Toji-myeon, Naeseo-ri, Piagol valley, N35.26590, E127.58096, alt. 446 m, 2015.07.0 1 (3), S. Podenas, at light (NIBR); female (preserved in ethanol), S. Korea, Jeollanam-do, Gurye-gun, Toji-myeon, Naeseo-ri, Piagol valley, N35.27177, E127.57146, alt. 490 m, 2015.07.0 2 (3), S. Podenas (NIBR).

Also compared with:

L. plutonis: female (pinned), Japan, Aomori, Tsutanuma Path, Okuse, Towada City, July 13, 2014, D. Katô leg.; female (pinned), Japan, Aomori, Ôkawa Path, Kawaratai, Nishimeya Vill., Sep. 1, 2014, D. Katô leg.; male (pinned), Japan, Fukuoka, Ino Dam, Ino, Hisayama-machi, May 1, 2015, D. Katô leg.; male (in ethanol), Japan, Nagano, Mt. Ontake-san, Ôtaki-mura, alt. 1840 m, 25.VI–15.VII.2015, S. Shimizu leg. (MT);

L. ladogensis: pictures of Lectotypus Limonia ladogensis Lack., design. Savchenko, female (pinned), Shlisselb, near village Mednaya, 29.V.1924, V. Barovskyi [label in Russian] and pictures of male collected in Russia [no label data]; female (pinned), Slovakia, Stakčin, Chotinka valley, 17.8.1989, J. Starý leg. and det.; male (pinned), Lithuania, Kaunas distr., Ringoves entomological sanctuary, 8.VI.1990, S. Podenas; male (in ethanol), Lithuania, Kaišiadorys distr., Būda forest, 1996.06.25, V. Podeniene; male and female (in ethanol), Lithuania, Kaišiadorys distr., Girelė, 1996.07.10, V. Podeniene; female wings (slide mounted), Lithuania, Švenčionys distr., Purviniškiai, N55.02851, E025.63159, altitude 145 m, July 3, 2007, S. Podenas.

Discussion. L. plutonis is most similar to L. ladogensis. Savchenko (1983, 1985), proposed that these species could be taxonomically identical, but later, Savchenko (1989), listed them as separate. Despite overall similarity, both species have a few small, but character-stable differences. The inner gonostylus of the male genitalia in L. plutonis is nearly rounded; in L. ladogensis this structure is elongated. The rostral prolongation of L. plutonis smoothly narrows towards the distal end, while the basal part of the rostral prolongation is swollen in L. ladogensis, and the second prolongation of the inner gonostylus is comparatively longer in L. plutonis, than in L. ladogensis. The most distinct difference is in the distal part of the paramere, which smoothly narrows towards the apex in L. ladogensis and is finger-shaped in L. plutonis. The hypogynial valve of the L. plutonis ovipositor reaches the apex of the cercus, while it is distinctly shorter in L. ladogensis. The general body coloration of L. plutonis is black, that of L. ladogensis is dark brown.