Distenia japonica Bates, 1873

Bi, Wen-Xuan & Lin, Mei-Ying, 2013, Description of a new species of Distenia (Coleoptera, Disteniidae, Disteniini) from Southeastern China, with records and diagnoses of similar species, ZooKeys 275, pp. 77-89 : 80-81

Distenia japonica Bates, 1873 Figs 16 -24 39-40

Distenia japonica Bates, 1873: 155.

Distenia gracilis : Kraatz 1879: 91; Švácha and Danilevsky 1987: 38 [part]; Lin et al. 2010: 120 [part].

Distenia gracilis gracilis : Ohbayashi and Niisato 2007: 335, pl. 1, figs 1 (male) & 2 (female) [Fauna].

Distenia japonica : Danilevsky 2012: 902.

Host plant.

It is polyphagous with the following host plants recorded under Distenia gracilis (confused with Distenia japonica ): Acer sp. (ACERACEAE), Abies sachalinensis Masters (PINACEAE), Alnus sp. (BETULACEAE), Betula sp. (BETULACEAE), Chosenia sp. (SALICACEAE), Picea sp. (PINACEAE), Pinus sp. (PINACEAE), Quercus sp. (FAGACEAE), Salix sp. (SALICACEAE), Ulmus sp. (ULMACEAE).

Diagnosis.

According to Danilevsky (2012), Distenia gracilis Blessig, 1872 (mainland and Sakhalin) and Distenia japonica Bates, 1873 (islands) are different vicariant species, very easily distinguished by narrow scapus in Distenia japonica . Further differences are shown in Table 1 .

Remarks.

This species was first described by Bates (1873) based on syntypes from Japan, Honshu (Hyogo Prefecture), Maiyasan, collected by George Lewis. Kraatz (1879) synonymized it with Distenia gracilis , which was widely followed by subsequent authors until Danilevsky (2012) resurrected it.

Švácha and Danilevsky (1987) pointed out the habit differences between the mailand population and island population, and suspected "it is possible that we are facing two separate taxa". "However, reliable larval morphological differences have not been found." ( Švácha and Danilevsky 1987). According to Danilevsky (2012), Distenia gracilis (mainland and Sakhalin) develops underground on healthy roots of living Chosenia (personal observation in Kedrovaya Pad) and on Alnus , but Distenia japonica lives under the old dead bark of many different trees (personal observation on Kunashir), often together with Eutetrapha . Therefore, the host plants recorded under Distenia gracilis could actually be host plants of Distenia japonica .

Distribution.

Japan, Russia (Far East, Islands).

Specimens examined.

Japan: 1 male, syntype, Japan (NHML, ex collection G. Lewis, examined through pictures); 1 male, Japan, Iwate Prefecture, Niisato-mura, Genbeidaira, 1982.VII.31, coll. N. Ohbayashi (CBWX); 1 female, Japon, Iwate Prefecture, Niisato-mura, Genbeidaira, 1982.VII.31, coll. N. Ohbayashi (CBWX); 1 male 1 female, Kyoto, Kibone, 1932.VII.1, coll. S. Yie (IZAS); 1 female, Tokushima, Mt. Tsurugi, 1971.VII.11, coll. H. Toshima (IZAS); 1 female, Tottori Pref., Mt. Hokki-Daisan, 1958.VII.22, coll. H. Toshima (IZAS).

Figures

Figures 16 - 18. Distenia japonica Bates, 1873. 16 male, from Iwate, Japan 17 syntype, male, from Hyogo, Japan 18 female, from Iwate, Japan a dorsal view b ventral view. Scale 5 mm.

Figures 19 - 24. Genitalia of Distenia japonica Bates, 1873. 19 - 23 male, from Kyoto, Japan 19 median lobe 20 rods of endophallus 21 hair-like thin rod of ejaculatory duct 22 tegmen. a ventral view b lateral view c dorsal view 23 tergite VIII in dorsal view 24 female, spermathecal capsule, from Kyoto, Japan. A-B from different sides. Scale 1 mm.

Figures 37 - 42. Six important characters of Distenia spp. not to scale. 37 - 38 Distenia gracilis. 37 male from Far East, Russia 38 female from Liaoning, China 39 - 40 Distenia japonica 39 male from Kyoto, Japan 40 female from Kyoto, Japan 41 - 42 Distenia orientalis sp. n. 41 male from Tianmushan, China 42 female from Tianmushan, China a last segment of maxillary palp, showing the tip and the ration of length to width b scape c pronotum d basal part of elytron e ventrite V f mesotibia of male, showing the apical protruding lobe.