Homoeusa longicornis Sharp, 1888

Homoeusa longicornis Sharp, 1888 View in CoL

Figs 2 C, F View Figure 2 , 3 D View Figure 3 , 11 A – K View Figure 11 , 12 A – F (Japanese name: Higenaga-hirata-ariyadori View Figure 12 )

Homoeusa longicornis Sharp, 1888: 283 (original description); Schülke and Smetana 2015; 682 (catalogue); Maruyama et al. 2013: 25 (distribution and bionomics mentioned). View in CoL

Type material.

Holotype (Fig. 2 C, F View Figure 2 ) • ♂; “ Homoeusa ” / “ longicornis ” / “ D. S. Type ” (written on the card which the specimen mounted) // “ Japan. ” / “ G. Lewis. ” / “ 1910–320 ” // “ Sapporo. ” / “ 5. VIII. – 16. VIII. 80. ” // “ Type ” (red round curator label) // “ HOLOTYPE ” / “ Homoeusa ” / “ longicornis ” / “ SHARP, 1888 ” / “ det. MARUYAMA, 2003 ” // “ NHMUK 014379776 ” (dissected by MM) ( NHM).

Additional material examined.

Japan: Hokkaido • 2 exs.; Hebinuma, Teshio-gawa, Teshio-chô ; 9. VII. 1992; S. Hori leg. ( KUM) • 2 ♂♂; Mukôengaru, Engaru-chô ; 25. V. 2000; Y. Kida leg. ( KUM) • 3 exs.; Kanayama, Makoi, Shari-chô ; 24. VI. 2002; Y. Kida leg. ( KUM) • 3 exs.; Taihei, Maruseppu, Engaru-chô ; 28. V. 2000; Y. Kida leg. LFcfF ( KUM) • 22 exs.; same locality; 29–31. V. 2000; Y. Kida leg. LFcfF ( KUM) • 11 exs.; same locality; 2–3. VI. 2000; Y. Kida leg. LFcfF ( KUM) • 1 ex.; same locality; 13. VI. 2000; Y. Kida leg. ( KUM) • 6 ♂♂, 5 ♀♀, 288 exs.; same locality; 16–17. VI. 2000; Y. Kida leg. LFcfF ( KUM) • 1 ♂, 7 exs.; same locality; 19–21. VIII. 2000; Y. Kida leg. LFcfF ( KUM) • 2 ♂♂, 1 ♀, 17 exs.; same locality; 25. VIII. 2000; Y. Kida leg. LFcfF ( KUM) • 1 ex.; Memanbetsu, Ôzora-chô ; 7. VIII. 2018; Y. Yoshimura leg. LFcfF ( KUM) • 1 ex.; Kashiwa-gaoka-kôen, Bihoro-chô , 23. VI. 2000; Y. Yamaga leg. ( KUM) • 1 ex.; Mitomi-shizenkôen, Bihoro-chô ; 13. VI. 2000; Y. Yamaga leg. ( KUM) • 2 exs.; Attoko, Nemuro-shi ; 30. VI. 1996; Y. Hirama leg. ( KUM) • 5 exs.; Ôsawaguchi, Nopporo-shinrin-kôen, Ebetsu-shi ; 2. VI. 1999; M. Maruyama leg. ( KUM) • 26 exs.; Ôsawaguchi, Nopporo-shizenkôen, Ebetsu-shi ; 16–19. VI. 2001; S. Hori leg. ( KUM) • 2 exs.; Mt. Maruyama, Sapporo-shi ; 6. VI. 1998; M. Maruyama leg. ( KUM) • 2 exs.; Tomanbetsu, Nopporo, Ebetsu-shi ; 29. V. 2002; M. Maruyama leg. LFcfF ( KUM) • 2 exs.; Shibumbersu, Nopporo-shinrin-kôen, Ebetsu-shi ; 11. V. 2000; M. Maruyama leg. LFcfF ( KUM) • 1 ex.; Mt. Moiwa, Sapporo-shi , 16. VI. 1983; Y. Hirano leg. ( KUM) • 10 exs.; Hitsujigaoka, Sapporo-shi ; 18. V. 2000; M. Maruyama leg. LFS ( KUM) • 24 exs.; Kannon-zawa, Sapporo-shi ; 1. VI. 2002; M. Maruyama leg. LFcfF ( KUM) • 1 ♂, 2 ♀♀, 24 exs.; same locality; 31. VI. 2002; M. Maruyama leg. LFcfF ( KUM) • 2 exs.; Hyakumatsuzawa, Sapporo-shi ; 8. VI. 1998; M. Maruyama leg. LFcfF ( KUM) • 4 exs.; Hakken-zan, Sapporo-shi ; 31. V. 2002; M. Maruyama leg. LFcfF & LU ( KUM) • 3 exs.; same locality; 1. VI. 2002; M. Maruyama leg. LFcfF & LU ( KUM) • 1 ex.; Yûtoku, Ôtaki-mura, Date-shi ; 24. VIII. 2001; M. Maruyama leg. ( KUM) . Honshu: Aomori-ken • 1 ex.; Yokonagare-tôge (alt. 300 m) [ 41.264, 141.314], Higashidori-mura ; 26. VI. 2023; TS. Nozaki leg. LFcfF ( KUM) GoogleMaps • 1 ♂, 1 ♀, 1 ex.; Kuromori (alt. 280 m) [ 40.677, 140.191], Ajigasawa-machi ; 24. VI. 2023; TS. Nozaki leg. LFcfF ( KUM) GoogleMaps • 1 ♀; Yunosawa, Tokiwano (alt. 490 m) [ 40.633, 140.268], Hirosaki-shi ; 25. VI. 2023; TS. Nozaki leg. LFcfF ( KUM) GoogleMaps . Miyagi-ken • 1 ♀; Toriido-yama, Komono-chô ; 2. VI. 2012; N. Tsuji leg. ( KUM) . Yamagata-ken • 1 ♂, 1 ex.; Senjuin, Yamadera (alt. 300–320 m) [ 38.319, 140.448], Yamagata-shi ; 15. VII. 2024; K. Mizota leg. LFcfF ( KUM) GoogleMaps . Fukushima-ken • 4 exs.; Kashi Spa., Nishigo-mura ; 16. VI. 1998; M. Maruyama leg. LFcfF ( KUM) • 1 ♀, 3 exs.; same locality; 17. VI. 1998; M. Maruyama leg. LFcfF ( KUM) • 1 ex.; Yukiwari-bashi, Nishigo-mura ; 29. VII. 2000; M. Maruyama leg. ( KUM) . Ibaraki-ken • 1 ex.; Sadanami, Sekimoto-chô, Kitaibaraki-shi ; 4. V. 2022; Y. Komatsuzaki leg. ( KUM) . Gunma-ken • 1 ex.; Tanigawa Spa, Minakami-chô ; 7. VI. 2001; T. Watanabe leg. ( KUM) • 1 ex.; Near Shima, Nakanojo-machi ; 12. VI. 1986; T. Katsumoto leg. ( SCM) • 2 ♂♂, 1 ♀, 4 exs.; Nakanojo Forest Park, Nakanojo-machi ; 8. VI. 2001; T. Watanabe leg. ( KUM) • 10 exs.; Sakurayama Park, Onishi, Fujioka-shi ; 9. V. 1998; Shiho Arai leg. LFS ( KUM) • 4 exs.; Mt. Sakurayama, Onishi, Fujioka-shi ; 9. V. 1998; K. Toyoda leg. LFS ( KUM) • 3 exs.; same locality; 18. V. 1998; K. Toyoda leg. LFS ( KUM) • 2 ♂♂, 3 ♀♀, 3 exs.; same locality; 22. V. 1999; Shiho Arai leg. LFS ( KUM) • 1 ex.; Shiozawa-toge, Fujioka-shi , 6. IX. 2001; T. Watanabe leg. ( KUM) . Saitama-ken • 1 ex.; Mt. Sakurayama, Onishi ; 2. V. 2009; K. Arai leg. ( KUM) • 2 exs.; Mt. Kamafuse yama, Fu-uppu (alt. 570 m), Yorii-machi ; 22. IV. 2006; K. Arai leg. LFcfF ( KUM) • 1 ex.; Chichibu-kôgen, Higashichichibu-mura ; 3. VII. 1999; K. Toyoda leg. ( KUM) • 6 exs.; Kasayama Sancho, Koshigoe, Ogawa-machi ; 30. IV. 2005; K. Arai leg. LFS ( KUM) • 2 exs.; Karibazaka Pass [ 35.9683, 139.1816], Tokigawa-machi ; 24. V. 2022; TS. Nozaki leg. LFcfF ( KUM) GoogleMaps • 2 exs.; Hashidate, Chichibu-shi ; 26. IV. 1998; K. Toyoda leg. LFS ( KUM) • 1 ex.; same locality; 26. IV. 1998; S. Arai leg. ( KUM) • 3 exs.; same locality; 7. VI. 2002; K. Toyoda leg. LFM ( KUM) • 1 ex.; Koakazawa, Irikawa, Mt. Hakutai-san, Ootaki (alt. 1,100 m), Chichibu-shi ; 7–8. VI. 2008; K. Arai leg. ( KUM) . Tokyo-to • 4 exs.; Mt. Takao, Hachiôji-shi ; 1. V. 1985; S. Kubota leg. ( KUM) • 2 exs.; Mt. Takaozan, Hachiôji-shi ; 26. IV. 1986; A. Izumi leg. LFS ( KUM) • 2 exs.; Mt. Takao, Hachiôji-shi ; 1. VII. 1998; M. Maruyama leg. LFS ( KUM) • 1 ex.; same locality; 4. VII. 1998; M. Maruyama leg. LFS ( KUM) • 1 ex.; Mt. Takao (alt. 500 m), Hachiôji-shi ; 1–4. VII. 1998; M. Maruyama leg. ( KUM) • 1 ♂, 1 ♀, 12 exs.; Mt. Takao (alt. 450 m), Hachiôji-shi ; 4. VI. 2001; M. Maruyama leg. ( KUM) • 1 ♂, 1 ex.; same locality, Hachiôji-shi ; 4. VI. 2001; M. Maruyama leg. LFS ( NHM) . Kanagawa-ken • 2 exs.; Hokizawa, Nishi-tanzawa ; 25–26. VI. 1983; Y. Hirano leg. ( KUM) • 1 ex.; Minami-Ashigara-shi ; 11. II. 1975; Y. Hirano leg. ( KUM) • 2 exs.; Mt. Daiyûzan, Minami-Ashigara-shi ; 28. VI. 1987; A. Izumi leg. LFcfF ( KUM) • 1 ex.; Daiyuzan, Hakone ; 26. V. 1986; Y. Shibata leg. ( KUM) • 1 ex.; Daiyuzan, Ashigara ; 21. V. 1989; Y. Shibata leg. ( KUM) • 2 exs.; Hakone ; 4. V. 1987; M. Tao leg. ( KUM) . Niigata-ken • 1 ex.; Ochinomizu, Tokamachi-shi ; 19. IV. 1998; T. Kishimoto leg. LFcfF ( KUM) • 1 ex.; Foot of Mt. Uedafuji, Yuzawa-machi ; 18. IV. 1998; H. Yoshitomi leg. ( KUM) • 1 ex.; Yuzawa-machi ; 20–22. VI. 2002; S. Nagashima leg. LFcfF ( KUM) . Yamanashi-ken • 1 ♂; Gozaishi-kôsen (alt. 900 m), Nirasaki-shi ; 25. VII. 2002; S. Nomura leg. LFN ( KUM) • 3 exs.; Ashiyu-onsen, Ashiyu-mura ; 23. V. 2001; T. Watanabe leg. ( KUM) • 1 ex.; same locality; 24. V. 2001; T. Watanabe leg. ( KUM) . Nagano-ken • 1 ex.; Midarebashi, Chikuhoku-mura ; 21. VII. 1999; T. Watanabe leg. ( KUM) • 1 ♂, 1 ex.; Ôkubo, Komoro-shi ; 29–30. IV. 2001; H. Kamezawa leg. LFcfF ( cKam) . Gifu-ken • 2 ♂♂; Bijo Pass, Takayama-shi ; 5. VIII. 2003; K. Kinomura leg. ( KUM) • 1 ♂, 1 ex.; Hirugano Bunsuirei Park, Gujo-shi ; 10. VI. 2013; K. Kinomura leg. ( KUM) • 1 ♂; Mt. Kentô, Takayama-shi ; 6. VII. 2003; K. Kinomura leg. ( KUM) • 2 ♂♂; Yôrô Park, Yôrô-chô ; 29. IV. 2004; K. Kinomura leg. ( KUM) . Shizuoka-ken • 2 exs.; Utsuno, Fujinomiya ; 30. V. 2000; T. Watanabe leg. Fish feed Bait, pinned with a Phidole ant det. by K. Matuura ( KUM) . Aichi-ken • 1 ♀; Jôkôji-kôen, Seto-shi ; 16. IV. 2023; T. Tenma leg. ( KUM) . Kyoto-fu • 1 ♂, 1 ex.; Tenno-zan, Oyamazaki-chô ; 16. IV. 2008; T. Ito leg. ( OMNH) • 2 exs.; same locality; 31. V. 2008; T. Ito leg. ( OMNH) • 1 ♀; Amagase Forest, Uji-shi ; 8. V. 2013; T. Ito leg. ( OMNH) • 1 ex.; Otokoyama, Yawata-shi ; 11. V. 2014; T. Ito leg. ( OMNH) • 1 ♂; same locality; 14. VI. 2008; T. Ito leg. ( OMNH) . Osaka-fu • 1 ♂; Mt. Mikusa, Nose-chô ; 21. VI. 2008; T. Ito leg. ( OMNH) • 1 ♂; Mino-o Park, Mino-shi ; 28. V. 2008; T. Ito leg. ( OMNH) . Hyogo-ken • 2 ♂♂, 1 ♀, 1 ex.; Dojo, Kobe-shi ; 13. IV. 2009; T. Ito leg. ( OMNH) . Nara-ken • 1 ♀; Yamato-Koriyama, Yata ; 9. VII. 2009; T. Ito leg. ( OMNH) • 1 ♂; same locality; 18. V. 2009; T. Ito leg. ( OMNH) . Wakayama-ken • 1 ♂; Kimitoge Pass, Hashimoto-shi ; 1. VI. 2009; T. Ito leg. ( OMNH) • 1 ♂; same locality; 27. IV. 2014; T. Ito leg. ( OMNH) . Tottori-ken • 1 ex.; Mt. Daisen, Daisen-chô ; 3–5. VI. 1980; S. Naomi leg. ( KUM) . Shimane-ken • 1 ♂; Urahikimi, Masuda-shi, Masuda-shi ; 6. VI. 1998; S. Nomura leg. LFS ( KUM) . Hiroshima-ken • 1 ♂; Mt. Iwahi (alt. 1,110 m) [ 35.0712, 133.2192], Shobara-shi ; 16. VI. 2024; TS. Nozaki leg. LFcfF ( KUM) GoogleMaps . Shikoku: Tokushima-ken • 2 exs.; Takashiro-yama, Naka-chô ; 24. V. 2007; H. Fujimoto leg. LFS ( KUM) . Kagawa-ken • 1 ex.; Ôtawa, Nagao, Sanuki-shi ; 22. V. 2000; F. Ito leg. ( KUM) • 2 exs.; Daisen-zan, Kotonami-chô ; 1. VI. 2001; M. Maruyama et al. leg. LFN ( KUM) • 1 ex.; same locality; 3. V. 2004; H. Fujimoto leg. LFcfF ( KUM) . Ehime-ken • 1 ♂, 1 ♀; Mt. Ishiduchi, Saijo-shi ; 29. VI. 2014; Y. Hisasue leg. ( KUM) . Kochi-ken • 1 ♂, 1 ♀; Hokigamine (alt. 500 m) [ 33.6719, 133.6846], Kami-shi ; 11. V. 2023; TS. Nozaki leg. LFS ( KUM) GoogleMaps .

Diagnosis.

This species is distinguished from the other species of the genus by the following combination of characteristics: pronotal posterolateral angle around 90 degrees (Fig. 11 C View Figure 11 ); elytra distinctly widened entirely posteriad (Fig. 11 C, D View Figure 11 ); apical lobe of paramere very long, length over half of whole paramere, curved ventrally, apex blade-shaped (Fig. 11 I View Figure 11 ). This species is quite similar to H. japonica in its general appearance but can be separated by the blade-like apex of its parameral apical lobe.

Redescription. Body (Figs 3 D View Figure 3 , 12 F View Figure 12 ) large, broad, stout; dorsal surface mostly moderately polished.

Head large; color reddish brown to dark brown; eyes small. Antennae (Fig. 11 A, B View Figure 11 ) very long.

Thorax. Pronotum (Fig. 11 C View Figure 11 ) subrectangular, transverse ( PW / PL, 1.53–1.64), widest anterior 1 / 3, postero-lateral angle around 90 degrees, posterior margin slightly sinuate, reddish yellow to reddish brown, surface finely covered with setae and punctures, gently polished and slightly reticulated. Elytra (Fig. 11 C, D View Figure 11 ) distinctly widened posteriad entirely, posterior margins shallowly notched near lateral corners, reddish yellow to reddish brown, surface finely covered with setae and punctures; gently polished and weakly reticulated. Hind wings developed. Mesoventral process (Fig. 11 E View Figure 11 ) very narrow, with weak medial carina, forming Y-shaped, apex sharply pointed, reaching posterior 1 / 3 of mesocoxal cavities. Metaventral process weakly produced.

Abdomen elongate, narrowed posteriad; surface covered with short setae and each posterior margin with long stout setae; finely reticulated.

Male: Relative length of each antennal segment from first to 11 th, 1.66: 1.13: 1.16: 1.07: 1.00: 1.04: 1.00: 1.06: 1.01: 1.13: 2.25. 8 th sternite (Fig. 11 F View Figure 11 ) weakly rounded at posterior margin; median lobe of aedeagus (Fig. 11 H View Figure 11 ) slender, length about 0.63 mm, apical lobe elongated, ventral side slightly humped at middle, apex gently pointed in lateral view, apical valves simple and very long, without dorsal arms, basal part of the copulatory piece very small. Paramere (Fig. 11 I View Figure 11 ) length about 0.79 mm; apical lobe of paramere extremely long, length over half of whole paramere, curved ventrally, dilated apicad, apex blade-shaped; four setae, a far longer than others, b located most apically, velum elongate, broad and produced apically.

Female: Relative length of each antennal segment from first to 11 th, 2.37: 1.57: 1.29: 1.09: 1.06: 1.00: 1.06: 1.08: 1.17: 1.40: 2.88. 8 th sternite (Fig. 11 G View Figure 11 ) truncated or slightly rounded at posterior margin; spermatheca (Fig. 11 J, K View Figure 11 ) S-shaped, apex of basal part not swollen, base largely hooklike.

Variation.

Apical lobe of aedeagal median lobe varies on the degree of dorsally curve, intension of middle hump ventral side, and depth of basal concave (Fig. 12 A – C View Figure 12 ) independently of geographical locations.

Measurements (in mm) and ratios.

Body parts (N = 12): BL ≈ 2.58–3.54; AL, 0.98–1.3; HW, 0.59–0.7; PL, 0.59–0.72; PW, 0.97–1.13; EL, 0.5–0.59; EW, 0.94–1.13; HTL, 0.65–0.8; PW / PL, 1.53–1.64; AL / PL, 1.5–1.91; HTL / PL, 0.98–1.13.

Differences between sexes: AL / PL (male, N = 5), 1.82–1.91; AL / PL (female, N = 7), 1.5–1.65; HTL / PL (male, N = 5), 1.05–1.13; HTL / PL (female, N = 7), 0.98–1.04.

Distribution.

Japan ( Hokkaido, Honshu, Shikoku) (Fig. 12 D View Figure 12 ).

Symbiotic hosts.

Lasius fuliginosus species group: L. cf. fuliginosus , L. morisitai , L. nipponensis , L. orientalis , L. spathepus .

Bionomics.

Homoeusa longicornis can be observed in Lasius fuliginosus species group foraging trails on the forest floor from April to August (Fig. 12 E View Figure 12 ). To the best of our knowledge, no individual was collected using FIT. The beetles were observed to be frequently raising the tip of their abdomen when approaching the host ant workers in the field and indoors.

Remarks.

This species is rarely collected from the trails of L. nipponensis and L. orientalis . This species is very similar to H. japonica in terms of its habitus (Fig. 12 F View Figure 12 ) and bionomics. H. longicornis tends to occur at higher altitudes than that of H. japonica . However, both species frequently co-occur at moderate altitudes in Honshu and Shikoku, even within the same colony of host ants. Precisely distinguishing between the two species is challenging without examining male genitalia. The pronotum length can be helpful; that of H. longicornis is usually longer than 0.65 mm, whereas that of H. japonica is shorter than 0.65 mm, but some exceptions remain in both species.