Lilioceris rugata (Baly, 1865)

Figs 2, 13, 19, 25, 31, 42, 45

Lilioceris rugata Baly, 1865: 154 (Japan, syntype, gender?). ( Crioceris). Chûjô 1941: 453 ( Lilioceris).

Type material examined.

1 type (NHML, photo), Type / Type / Japan / Crioceris Lilioceris rugata Baly, Japan / BMNH (E) 1342969.

Other material examined.

Total 10 specimens. 1♂ 1♀, Museum Paris, Nippon Moyen, env de Tokyo et alpes de Nikko, J. Harmand, 1901; 1♀, Karisnmi, 1932.VII.23; 1♂, Mont Takao, Pr. Hachigji, Japon: 1911.V.28, Edme Gallois / Lilioceris Rugata (Baly), Peiyu Yu Det.; 1♂, Kyoto, 1931.I.18, K. Eki; 1♂, Kibune, Kyoto, 1931.VI.14, K. Eki / Crioceris Lilioceris rugata Baly, det by S. Yie; 1♂, Japan, G. Lewis, 1910-320 / Crioceris Lilioceris rugata Baly, P. M. Hammond det. 1980; 1♂ 2♀, Karuizawa, 1907.IX.27 / Lilioceris rugata, det. Peiyu Yu.

Diagnosis.

Femora black; pronotum disc with large punctures; elytral punctures strong and not diminishing posteriorly, intervals convex apically; lateral side of metasternite nearly glabrous, without strip of pubescence; abdominal sternites smooth.

Redescription.

BL = 6.9-8.0 mm, BW = 3.2-3.8 mm. Head, legs, and ventral surfaces black, pronotum, scutellum, and elytra brownish red.

Head (Fig. 2). HL/HW = 1.3-1.4; vertex with groove and fovea in the middle, punctate and setose laterally; frontoclypeal area triangular, disc with fine punctures and sparse setae; labrum transverse, with long setae on both apical angles; antennomeres 5-7 nearly 1.5 times as long as wide, 8-10 slightly longer than width (Fig. 31).

Pronotum (Fig. 13A). PW / HW = 1.0-1.2, PL / PW = 1.0-1.3; anterior angle slightly protruding; posterior angle not protruding; sides slightly constricted in the middle; middle of disc with large and deep punctures; anterior and posterior transverse impressions indistinct, basal transverse groove shallow.

Elytra (Fig. 13D). EL/EW = 1.5-1.7; sutural angle rounded; humeri protruding, humeral groove shallow, basal transverse impression indistinct; scutellary striole composed of 4-7 punctures; strial punctures large, not diminishing posteriorly, intervals convex at apical 1/4; epipleura raised, with row of fine punctures.

Mesosternite pubescent. Lateral side of metasternite nearly glabrous, with little pubescence along anterior and posterior margins (Fig. 13B); metepisternum densely pubescent.

Abdominal sternites nearly smooth (Fig. 13C).

Legs slender; tibiae with dense punctures and pubescence; femora with dense pubescence on the dorsal surface, with sparse pubescence on the ventral surface.

Male genitalia (Fig. 19A-D). Median foramen occupying 1/5 length of median lobe (Fig. 19A); apex rounded (Fig. 19B); basal piece of the tegmen triangular, lateral lobes weakly sclerotized; posterior part of dorsal sclerite in dorsal view widely rounded, directed laterally (Fig. 19C, D).

Female reproductive organs (Fig. 25A-C). Spiculum gastrale short, X-shaped, distal part strongly widened, apical margin straight; ovipositor with dense setae, distal part of ovipositor cylindrical and short, with a small protuberance; spermatheca small and greatly convoluted.

Host plant and habitat.

This species feeds on Dioscorea japonica and D. tokoro (Kimoto, 1964). The habitat is unknown.

Distribution.

Japan.

Remarks.

This species is similar to L. sinica, but differs from the latter by having its pronotal disc with strong and deep punctures, metasternite and abdominal sternites nearly smooth (in L. sinica, pronotal disc with fine and shallow punctures, lateral side of metasternite with a wide strip of pubescence, and abdominal sternites densely pubescent except the glabrous abdominal transverse impressions). In addition, the genitalia of L. rugata differ from those of L. sinica by posterior part of dorsal sclerite in dorsal view widely rounded, directed laterally (in L. sinica, posterior part of dorsal sclerite in dorsal view slightly narrowed at apex, more or less parallel-sided). Chûjô (1941) synonymized L. sinica with L. rugata, which is not justified in the light of the present study.

Lilioceris rugata is widely distributed in Japan, obviously isolated geographically from other species in China, Russian and Korea. The records of this species from Russia and Korea are questionable. We found some photographs identified as L. rugata on websites from Russia (https://www.zin.ru/animalia/coleoptera/eng/lilrugkm.htm) and Korea (https://blog.naver.com/onegunah/110021296278) that are actually L. theana . Cho and An (2020) recorded nine specimens of L. rugata collected from South Korea. They are probably also L. theana (see Cho and An 2020: 7, fig. 13). The materials of L. rugata from Russia and Korea need more study.