Georissus (Neogeorissus) japonicus Satô, 1972

Yasuda, Kohei & Yoshitomi, Hiroyuki, 2022, Revision of the genus Georissus (Coleoptera, Hydrophiloidea, Georissidae) of Japan, European Journal of Taxonomy 817 (1), pp. 111-142 : 124-126

Georissus (Neogeorissus) japonicus Satô, 1972

[Japanese name: Yamato-marudoromushi]

Figs 2D , 3D–F, J–L , 4C, F, I, L, O , 5D , 6D , 7D , 8D , 9D , 10C , 11A, 11E ; Table 2

Georissus (Neogeorissus) japonicus Satô, 1972: 210 .

Georissus (Neogeorissus) sakaii Satô, 1972: 210 . Syn. nov.

Georissus (Neogeorissus) katsuoi Nakane, 1995: 42 . Syn. nov.

Georissus (Neogeorissus) japonicus – Satô 1981: 3; 1985: 206. — Hansen 1999: 47.

Georissus (Neogeorissus) sakaii – Satô 1981: 3; 1985: 206. — Hansen 1999: 49.

Georissus (Neogeorissus) katsuoi – Hansen 1999: 47.

Diagnosis

This species is distinguished from other Japanese Neogeorissus species by the combination of following characteristics; distinct granulation of pronotum and elytra; median lobe shorter than paramere (in contrast to median lobe longer than paramere in other Japanese species of Neogeorissus ).

Material examined

Holotype of G. (Ne.) japonicus Satô, 1972

JAPAN – Honshu: Niigata Pref. • ♂; Murakami; 8 Aug. 1961; M. Satô leg.; EUMJ ( Fig. 3 D, J ) .

Holotype of G. (Ne.) sakaii Satô, 1972

JAPAN – Shikoku: Tokushima Pref. • ♂; Tsuda Beach; 11 Sep. 1966; M. Sakai leg.; EUMJ ( Fig. 3 E, G ) .

Holotype of G. (Ne.) katsuoi Nakane, 1995

JAPAN – Honshu: Miyagi Pref. • sex unknown; Water-machi, Torinoumi ; 26 Aug. 1993; K, Saito leg.; SEHU ( Fig. 3 F, I ) .

Other material

JAPAN – Honshu: Niigata Pref. • 4 ex.; Murakami; 8 Aug. 1961; M. Satô leg.; EUMJ. – Honshu : Shizuoka Pref. • 1 ex.; Hamamatsu , Ishiyama ; 25 May 2001; K. Hirai leg.; EUMJ • 1 ex.; Hamamatsu , Enshuhama ; 4 Oct. 2001; K. Hirai leg.; EUMJ • 3 ex.; Hamamatsu , Enshuhama ; 13 Oct. 2001; K. Hirai leg.; EUMJ • 6 ex.; Hamamatsu-shi, Matsushima-cho, Enshuhama; 13 Oct. 2002; K. Hirai leg.; EUMJ. – Kyushu : Fukuoka Pref. • 8 ex.; Kouge-machi , Shimotoubaru ; 23 Jul. 2013; M. Mori leg.; EUMJ .

Redescription

COLORATION ( Fig. 2D ). Black to dark brown, matt. Body surface often covered with grayish substance.

HEAD ( Fig. 6D ). Clypeus uneven, provided with large granules sparsely; slr consisted of granules, reaching to posterior third of frons, posteriorly connected to smb by an arc of sparsely arranged granules and formed a pair of half-rounded foveae; smb consisted of tubercles and granules, anterior portion projecting to laterally; lsa with a shallow groove along the posterior margin.

PRONOTUM ( Fig. 7D ). Relatively large, widest at the middle. Anterior portion provided with granules densely; smlg relatively wide, granulation dense, with longitudinal row of sparse pits. Posterior portion somewhat convex than anterior portion; cd rhomboid, surrounded by granules; s dp oblong oval, larger than cd, surrounded by granules; slb developed, with distinct granules; pg short and narrow, not reaching median portion of sdp; sdn developed, having a few teeth.

ELYTRA. Humeral bulges distinct. All intervals slightly elevated, provided with distinct lows of granules. Elytral punctures distinct. Lateral ridges on each elytron highly elevate, bearing distinct granules. Hind wings fully developed.

ABDOMEN ( Fig. 8D ). Lateral margin of ventrites uniformly narrowing posterior. Granules of ventrite 1 large and dense. Granulation of ventrites 2–4 indistinct, ventrite 5 distinct and sparse.

MALE GENITALIA ( Fig. 9D ). Aedeagus 0.30 mm long. Parameres shorter than phallobase, their basal portions combined as wide as anterior portion of phallobase; lateral margins bulbous at median portion; internal margins straight. Median lobe shorter than parameres, subparallel-sided, slightly angular at apex; basal struts short. Phallobase about 2.5 times as long as wide, sides paralleled: posterior portion with large basal foramen.

FEMALE GENITALIA. Latero-tergites 8 forming acute angle ( Fig. 10C ); apex strongly incurved. Setae of gonostylus short. Spermatheca ( Fig. 11E ) curved oval, narrowing at apical portion. Bursal sclerite ( Fig. 11A ) large and asymmetrical, feebly sclerotized.

Remarks

Satô (1972) mentioned that Georissus (Neogeorissus) sakaii was closely related to G. japonicus and distinguished by granules and foveae on body surface. Subsequently, Nakane (1995) described Georissus (Neogeorissus) katsuoi as a new species without comparison with the related species G. sakaii and G. japonicus . Both species were described based on only holotypes, and there have been no additional records until now. After a detailed comparison of holotype and additional specimens of the above three species, we conclude that they are the same species.

Biological notes

This species was collected from coastal sandy beaches (Shizuoka, Tokushima), a river bank ( Iwata & Iwata 2012, in Saitama by pit fall trap), or the shores of ponds (Niigata, Fukuoka).

Distribution

Russian Federation (Lafer 1989); Japan: Honshu (Miyagi, Ibaraki, Niigata, Shizuoka Prefs), Shikoku (Tokushima Pref.), Kyushu (Fukuoka Pref.) ( Fig. 13 ).

Figures

Fig. 2. Dorsal view of Georissus spp. A. G. (G.) canalifer Sharp, 1888. B. G. (G.) babai Satô, 1970. C. G. (Ni.) granulosus Satô, 1972. D. G. (Ne.) japonicus Satô, 1972. E. G. (Ne.) kurosawai Nakane, 1963. F. G. (Ne.) takahashii sp. nov., holotype, ♂ (EUMJ). G. G. (Ne.) satoi sp. nov., holotype (EUMJ). Scale bars = 0.5 mm.

Fig. 3. Holotypes of Georissus spp. A–F. Dorsal habitus. G–L. Labels. A, K. G. (G.) babai Satô, 1970, ♂ (EUMJ). B, L. G. (Ni.) granulosus Satô, 1972, ♀ (EUMJ). C, H. G. (Ne.) kurosawai Nakane, 1963, ♂ (SEHU). D, J. G. (Ne.) japonicus Satô, 1972, ♂ (EUMJ). E, G. G. (Ne.) sakaii Satô, 1972, ♂ (EUMJ). F, I. G. (Ne.) katsuoi Nakane, 1995 (SEHU). Scale bars = 0.5 mm.

Fig. 4. Mouth parts and antennae of Georissus spp. A–C. Left maxillae. D–F. Labrum. G–I. Labial palpi. J–L. Left mandibles. M–O. Left antennae. A, D, G, J, M. G. (G.) canalifer Sharp, 1888. B, E, H, K, N. G. (Ni.) granulosus Satô, 1972. C, F, I, L, O. G. (Ne.) japonicus Satô, 1972. Scale bars = 0.1 mm.

Fig. 5. Dorsal habitus of Georissus spp. A. G. (G.) canalifer Sharp, 1888. B. G. (G.) babai Satô, 1970. C. G. (Ni.) granulosus Satô, 1972. D. G. (Ne.) japonicus Satô, 1972. E–F. G. (Ne.) kurosawai Nakane, 1963 from Hokkaido (E) and Nagano (F). G–H. G. (Ne.) takahashii sp. nov. from Kochi (G) and Okinawa (H). I. G. (Ne.) satoi sp. nov.

Fig. 6. Head of Georissus spp. A. G. (G.) canalifer Sharp, 1888. B. G. (G.) babai Satô, 1970. C. G. (Ni.) granulosus Satô, 1972. D. G. (Ne.) japonicus Satô, 1972. E–F. G. (Ne.) kurosawai Nakane, 1963 from Hokkaido (E) and Nagano (F). G–H. G. (Ne.) takahashii sp. nov. from Kochi (G) and Okinawa (H). I. G. (Ne.) satoi sp. nov.

Fig. 7. Pronotum of Georissus spp. A. G. (G.) canalifer Sharp, 1888. B. G. (G.) babai Satô, 1970. C. G. (Ni.) granulosus Satô, 1972. D. G. (Ne.) japonicus Satô, 1972. E–F. G. (Ne.) kurosawai Nakane, 1963 from Hokkaido (E) and Nagano (F). G–H. G. (Ne.) takahashii sp. nov. from Kochi (G) and Okinawa (H). I. G. (Ne.) satoi sp. nov.

Fig. 8. Ventrites of Georissus spp. A. G. (G.) canalifer Sharp, 1888. B. G. (G.) babai Satô, 1970. C. G. (Ni.) granulosus Satô, 1972. D. G. (Ne.) japonicus Satô, 1972. E–F. G. (Ne.) kurosawai Nakane, 1963 from Hokkaido (E) and Nagano (F). G–H. G. (Ne.) takahashii sp. nov. from Kochi (G) and Okinawa (F). I. G. (Ne.) satoi sp. nov. Abbreviation: vt = ventral teeth. Scale bars = 100 μm.

Fig. 9. Male aedeagus of Georissus spp. A. G. (G.) canalifer Sharp, 1888. B. G. (G.) babai Satô, 1970. C. G. (Ni.) granulosus Satô, 1972. D. G. (Ne.) japonicus Satô, 1972. E. G. (Ne.) kurosawai Nakane, 1963. F–G. G. (Ne.) takahashii sp. nov. from Kochi (F) and Okinawa (G). H. G. (Ne.) satoi sp. nov. Scale bar = 0.1 mm.

Fig. 10. Female ovipositor of Georissus spp. A. G. (G.) canalifer Sharp, 1888. B. G. (G.) babai Satô, 1970. C. G. (Ne.) japonicus Satô, 1972. D. G. (Ne.) kurosawai Nakane, 1963. E. G. (Ne.) takahashii sp. nov. F. G. (Ne.) satoi sp. nov. Abbreviations: gsty = gonostylus; ltg8 = latero-tergite 8. Scale bar = 0.1 mm.

Fig. 11. Female genital organs of subgenus Neogeorissus spp. A–D. Bursal sclerite. E–H. Spermatheca. A, E. G. (Ne.) japonicus Satô, 1972. B, F. G. (Ne.) kurosawai Nakane, 1963. C, G. G. (Ne.) takahashii sp. nov. D, H. G. (Ne.) satoi sp. nov. Scale bar = 0.1 mm.

Fig. 13. Distribution map of Georissus spp. Russian localities for Georissus (G.) canalifer Sharp, 1888 and G. (Ne.) japonicus Satô, 1972 are omitted.