Anthocoris venustus, Yamada & Yasunaga, 2021

Yamada, Kazutaka & Yasunaga, Tomohide, 2021, The tribe Anthocorini in Japan (Hemiptera: Anthocoridae): descriptions of new species, review of distribution and bionomics, Acta Entomologica Musei Nationalis Pragae 61 (2), pp. 375-426 : 411-416

Anthocoris venustus sp. nov.

( Figs 8E–H , 9G , 11C–D , 12G , 14D–F , 15G , 16F , 22 ) Anthocoris miyamotoi (misidentification): Hංඎඋൺ (1959): 3 (description,in part);KൾඋඓHඇൾඋ (1988):774 (in key); Mංඒൺආඈඍඈ & YൺඌඎඇൺGൺ (1989): 165 (listed, distribution); TඈආඈKඎඇං (1992): 158 (record); TඈආඈKඎඇං (1993): 168 (diagnosis, habitat, distribution); YඈඌHංඍඈආං (1994): 26 (record); Pඣඋංർൺඋඍ (1996): 113 (catalogue,distribution);Iංඃංආൺ (1997): 15 (record); Yൺආൺආඈඍඈ (1997): 15 (record); YൺඌඎඇൺGൺ (1997b): 224 (record); TൺKൾඇඈ (1998): 44 (listed, associated plant); Yൺආൺආඈඍඈ (1999): 94 (record); Yൺආൺආඈඍඈ (2001): 5 (record); KൺඇඒඎKඈඏൺ & MൺඋඎඌංK (2006):168 (record);VංඇඈKඎඋඈඏ et al.(2010):57 (catalogue, distribution);Yൺආൺආඈඍඈ (2011):4 (record);Yൺආൺൽൺ et al. (2016):422 (catalogue, distribution); NൺKൺඍൺඇං (2019): 94 (record).

Type locality. Japan, Hokkaido,Hiyama-gun, Kaminokuni-cho,Yunotai. Type material. Hඈඅඈඍඒඉൾ: J ( Figs 8E–F ), ‘JAPAN/ Hokkaido \ Yunotai, Hiyama \ 19. viii. 1994 \ T. Yasunaga leg.’ [printed], ‘On Salix sp. ’ [printed]; mounted on a triangular card, in intact condition ( TKPM). Pൺඋൺඍඒඉൾඌ: JAPAN: HඈKKൺංൽඈ: 2 JJ 1 ♀, Wakkanai-shi, 15.ix.1974, Y. Furuki ( EUM); 4 JJ 1 ♀, Horokanai-cho, Moshiri, 3.viii.1994, on Salix sp. , Y. Tôdo (1 J 1 ♀ TKPM, 2 JJ NMPC); 1 J 2 ♀♀, Horokanai-cho, Moshiri-Shirakaba, 2.–7.viii.1994, on Salix sp. , T. Yasunaga (2 ♀♀ TKPM, 1 J ZMAS); 1 J, Monbetsu-shi, Kônomai, 3.viii.1997, S. Yamashita ( TKPM); 1 J 2 ♀♀, Higashikawa-cho, Mt. Asahi-dake, 200–800 m, 9.–10.viii.1994, on Salix sp. , Y. Tôdo (1 J 2 ♀♀ TKPM, 1 ♀ ZMAS); 1 J, Higashikawa-cho, Mt. Asahi-dake, 800 m, 9.viii.1994, R. Matsumoto ( TKPM); 1 J 1 ♀, Higashikawa-cho, Tennin-kyô Valley, 11.viii.1994, on Salix sp. , Y.Tôdo ( TKPM); 1J 1♀, Shintotsukawa-cho, 26.vii.1998, S. Gotoh ( TKPM); 3JJ 4♀♀ (one in Fig. 15G ), Shari-cho, Mt. On-nebetsu-dake, Opekepu-rindô, 31.viii.–1.ix.1995, T. Yasunaga & Y. Tôdo (1 J 3 ♀♀ TKPM, 2 JJ 1 ♀ AMNH); 1 J, Akkeshi-cho, Suminoe, 4.viii.2004, R. Matsumoto ( OMNH); 1 J 2 ♀♀, Kushiro-cho, Takkobu, 30.viii.1995, on Salix sp. , Y.Tôdo (1 J TKPM, 2♀♀ NMPC); 1 ♀, Kushiro-cho, Iwabokki-suimon, 28.viii.1995, on Salix sp. , M.Ozaki ( TKPM); 4 JJ (one in Figs 9G , 11C–D , one in Figs 12G , 14D–F ) 1 ♀, Makubetsu-cho, Chûrui, Kimontô, 21.viii.1995, on Salix sp. , T.Yasunaga & Y. Tôdo ( TKPM); 1 ♀, Nakasatsunai-mura, Pyoutan-no-Taki Fall, 16.vii.2000, light trap, K.Yamada ( TKPM); 1J, Urakawa-cho,Nishicha, Hidaka-horobetsu-gawa Riv., 18.viii.1995, on Salix sp. , Y.Tôdo ( TKPM); 1 ♀, Tobetsu-cho, Aoyama, 14.vii.1997, A. Makino ( TKPM); 1 J, same locality, on Fraxinus mandshurica , 26.vii.1997, T. Yasunaga ( TYCN); 1 ♀, Atsuta Village, Hatsutari, on Juglans mandshurica , 7.viii.1998, T. Yasunaga ( TYCN); 1♀, Tobetsu-cho, Ishikari-gawa Riv., 17.vii.1997,A. Makino ( TKPM); 1♀, Sapporo-shi,Mt.Moiwa, 3.viii.1970, S. Kinoshita ( EUM); 1J, Sapporo-shi, Otarunai-gawa-oku-rindô, 43.082N, 141.106E, 28.vii.2019, A. Yamamoto ( TKPM); 1 ♀, Otaru-shi, Nagahashi-Naebo, 43.213N, 140.977E, 18.v.2018,A.Yamamoto ( TKPM); 2♀♀, Otaru-shi, Asari-tôge, 23.vii.1995, on Salix sp. , Y.Tôdo ( TKPM); 1J, same locality, 18.viii.1996, on Alder, collector unknown ( TKPM); 1 ♀, Niseko, Mt. Chise-nupuri, 500–600 m, 9.vii.1994, on Quercus crispula, T. Yasunaga (TKPM) ; 1 ♀, Chitose-shi, Lake side of Shikotsu-ko, 5.–6.viii.1984, Y. Honda ( EUM); 1 ♀, Toyo-ura-cho, Iburi, 21.viii.1997, T. Yasunaga ( TYCN). Rebun-tô Is.: 2 JJ, Hamanaka, 22.ix.1991, M. Tomokuni ( NSMT); 1J, Kabukai,Rebun-rindô, 23.ix.1991, M.Tomokuni ( NSMT). Rishiri-tô Is.: 2JJ 1♀, Oshidomari, 17.ix.1991, M.Tomokuni ( NSMT); 1 ♀, Oniwaki, 28.–29.vii.1994, on Salix sp. , Y. Tôdo ( TKPM); 1 J, no detailed locality, 16.–17.ix.1974, Y. Furuki ( EUM). HඈඇඌHඎ: Aomori Pref.: 1♀, Mutsu-shi,Sekine, 31.v.1982, B. Tanaka ( TKPM). Iwate Pref.: 1 ♀, Yahaba-cho, Mt. Nansyou-zan, 1.vii.2004, T. Ishizaki ( TKPM). Tochigi Pref.: 1J, Nasushiobara-shi, Nakagawa-kahan-kôen, 4.viii.2016, S. Maehara ( TKPM); 1J, Nikko-shi, Kawamata, 27.ix.2019, S. Maehara ( TKPM); 1 ♀, Nikko-shi, Yumoto, 21.v.2007, S. Maehara ( TKPM); 1 J( Fig. 8G ), Nikko-shi, Ryû-oh-kyô, 19.vii.2010, S. Maehara ( TKPM); 1 J 1 ♀, Nikko-shi, Shôbugahama, 5.viii.2010, S. Maehara ( TKPM); 1 ♀, Nikko-shi, Chȗgȗshi, Asegata, 18.ix.2020, S. Maehara ( TKPM); 1 ♀, Shimotsuke-shi,Hosoya, 4.xi.2000, S. Maehara ( TKPM); 1♀, Mooka-shi, Isagahara, 6.vi.2018, S. Maehara ( TKPM); 1 ♀, Tochigi-shi, Hoshino- -machi, 6.iii.1991, H.Yoshitomi ( EUM); 1♀, Tochigi-shi, Oominagawa, 6.i.1994, H. Yoshitomi ( EUM). Nagano Pref.: 1 ♀, Kijimadaira-mura, Kayanodaira, 1.v.2000, Y. Kita ( TKPM). Gifu Pref.: 1 ♀, Takayama-shi, Hirayu, 28.vii.1959, M. Miyatake ( EUM). Aichi Pref.: 1♀, Toyone-mura, Mt.Chausu-yama, 15.–16.vii.1974,Y.Hori ( TKPM). Nara Pref.:1J ( Fig. 8H ), 2 ♀♀, Kamikitayama-mura, Ôdaigahara, 16.viii.2004, K. Yamada ( TKPM); 1J 2 ♀♀, same locality, 14.–15.xi.2004, K.Yamada ( TKPM); 1 ♀, Nosegawa-mura, Mt. Obako-dake, 25.v.2000, K. Yamada ( TKPM). SHංKඈKඎ: Tokushima Pref.: 2JJ 1 ♀, Naka-cho, Kisawa, 16.viii.1998, M. Takai ( TKPM); 1♀, Naka-cho, Kawanari-tôge, 6.vii.2011, K.Yamada ( TKPM); 1 J, Naka-cho, Iwakura, 23.viii.2010, K. Yamada ( TKPM); 1 unsexed, Naka-cho, Ichinomori to Nishijima, 16.vii.1984, M. Miyatake ( EUM); 1 J, Mt. Tsurugi, 14.viii.1959, I. Hiura ( OMNH). Ehime Pref.: 1 ♀, Kumakôgen-cho, Omogo-kei, 26.iv.1958, Y. Takaishi ( EUM); 1 ♀, Kumakôgen-cho, Ishizuchi-san, 13.vii.2021, H. Yoshitomi ( EUM). Kochi Pref.: 1 J, Ôtoyo-cho, Mt. Kajigamori, 20.viii.1959, K. Morimoto ( ELKU). KඒඎඌHඎ: Fukuoka Pref.: 2 JJ 2 ♀♀, Soeda-machi, Mt. Hikosan, 8.–11.ix.1997, T. Ishikawa ( TKPM); 1 ♀, same locality and date, T. Shimada ( TKPM). Oita Pref.: 1 ♀, Yufu-shi, Syônai-cho, Oike, 27.vii.1995,Y.Nakatani ( TKPM); 1♀, Mt.Kujyû, 9.iv.1959,Y. Miyatake ( OMNH). Miyazaki Pref.: 1 ♀, Gokase-cho, Mt. Shiraiwayama, 22.–24. vii.2016, T. Yoshida ( TKPM).

Differential diagnosis. Recognized by the following combination of characters: head and pronotum uniformly black to blackish brown ( Figs 8E–H ); clavus with basal and apical portions blackish brown, inner margin narrowly darkened; endocorium with basal and apical portions mostly blackish brown; embolium with basal and apical portions blackish brown; median portion of clavus and outer part of median portion of endocorium and remaining area of embolium whitish and subhyaline; area in front of cuneal fracture whitish or subhyaline; outer (posterior) margin of ostiolar peritreme not close to supracoxal area ( Fig. 9G ); paramere ( Figs 11C–D , 14E–F ) slender and very slightly curved, with longitudinal groove in form of shallow depression; copulatory tube ( Fig. 15G ) approximately 0.8 mm in length, basally thickened, with a few twists. Closely related to A. miyamotoi but distinguished from that species by the uniformly blackish head and pronotum, slender and very slightly curved paramere, and copulatory tube longer and basally thickened with a few twists.

Description. Coloration. Body ( Figs 8E–H , 16F ) generally black to blackish brown. Head and pronotum ( Figs 8E, G–H ) blackish brown, sometimes vertex and callus tinged with reddish brown; eyes reddish black; margin of ocellus red to reddish brown. Antennal segment I dark brown; segment II yellowish brown, dark brown on base and apical 1/4 to 1/3; segment III yellowish brown, dark brown on apical half; segment IV dark brown. Labium ( Fig. 8F ) uniformly black to blackish brown. Scutellum overall black to blackish brown. Clavus with basal portion and apex blackish brown, inner margin narrowly darkened ( Figs 8E,G–H ); endocorium with basal and apical portions mostly blackish brown ( Figs 8E,G–H ); embolium with basal and apical portions blackish brown ( Figs 8E,G–H ); cuneus wholly blackish brown; median portion of clavus and outer part of median portion of endocorium and remaining area of embolium whitish and subhyaline ( Figs 8E,G–H ); area in front of cuneal fracture whitish or subhyaline; membrane smoky dark brown, with basal and innermost portions and area behind apex of cuneus off- white ( Figs 8E,G–H ). Legs dark reddish brown; trochanters tinged with yellowish brown; apical half or apical 2/3 of protibiae sometimes tinged with yellowish brown. Venter of thorax uniformly blackish brown.Abdomen black to blackish brown. Pygophore blackish brown with pale yellow paramere.

Structure. Body ( Figs 8E–H ) elongate, shiny on dorsal and ventral surfaces, sparsely covered with suberect, simple, yellowish setae. Head ( Figs 8E–H ) cylindrical, impunctate, approximately as long as width across eyes; three pairs of long, erect trichobothria on the dorsal surface of head, one on anterior clypeus, one in front of eye, and one behind ocellus; anteocular region as long as length of eye in dorsal view in male, slightly longer than length of eye in female; vertex approximately twice as wide as eye in dorsal view in male, approximately 2.5 times as wide as eye in female; postocular region constricted, demarcated by transverse shallow furrow; neck long, smooth, highly polished; eye oblong, not exceeding level of dorsal surface of head in lateral view but exceeding level of ventral surface of head. Antennae ( Figs 8E–H ) densely covered with short, decumbent, yellowish setae interspersed with long, erect setae, of which the longest are as long as or slightly shorter than width of corresponding segment; segment I just reaching apex of head, sparsely covered with short setae; segment II gradually thickened toward apex, slightly thicker in the male than in the female, approximately as long as head width across eyes; segment III approximately 0.7 times as long as segment II; segment IV longer than segment III. Labium ( Fig. 8F ) just reaching procoxae; segment III approximately 4.0–5.0 times as long as segment II; segment IV approximately half as long as segment III.

Pronotum ( Figs 8E,G–H ) with pairs of long, erect trichobothria on midline of collar and on each anterior and posterior angle; anterior margin very slightly curved, approximately 0.7 times as long as mesal length; lateral margin very slightly curved; lateral carina slightly expanded anteriorly, more obscure posteriad; posterior margin concave inwardly, approximately 2.5 times as wide as anterior margin; collar long, transversely rugose, with scattered long setae; callus extremely swollen, polished, impunctate, sides strongly bulging, demarcated posteriorly by deep transverse impression; deep impression with short parallel carinae and coarse punctures; posterior lobe behind callus densely covered with minute punctures. Scutellum ( Figs 8E,G–H ) smooth, sub-equilateral, wider at base than long, depressed through middle. Hemelytra ( Figs 8E–H ) sparsely covered with long, erect, simple, yellowish setae, and with minute punctures; costal margin slightly sinuate; endocorium approximately 1.6 times as wide as maximum width of embolium; cuneal margin approximately 0.7 times as long as embolial margin; membrane with three veins, outermost vein distinct and slightly curved, inner two veins obscure and very slightly curved. Ostiolar peritreme ( Fig. 9G ) wide, gently curved anteriorly, gradually narrowing toward apex and then continued by a fine carina that reaches the anterior margin of metapleura; outer (posterior) margin of ostiolar peritreme not close to supracoxal area; evaporatorium bearing a small number of long, recumbent setae. Fossula spongiosa present on apex of all tibiae, enlarged on protibiae and small on meso- and metatibiae; apical 1/4 of metatibiae bearing small spines on ventral side. Abdominal sternum III ( Fig. 12G ) with a pair of banana-shaped membranous areas on anterior half, membranous area somewhat widened near base; dorsal laterotergites not fused with mediotergites on abdominal segments II and III.

Male genitalia ( Figs 11C–D , 14D–F ): Pygophore ( Fig. 14D ) rather pointed apically, asymmetrical, covered with 6–8 long, stout setae intermixed with short, suberect setae along outer margin and on posteroventral surface, of which the longest are approximately half length of pygophore; mid-dorsal surface hirsute with suberect setae; paramere ( Figs 11D , 14E–F ) slender, very slightly curved but bent at basal 1/3, with a few very short, erect setae on sub-basal portion, the apex hooked and reaching nearly half of the left outer margin of pygophore; longitudinal groove in form of shallow depression, twisted basally.

Female genitalia ( Fig. 15G ): Copulatory tube fused on middle of intersegmental membrane between sterna VII and VIII, approximately 0.8 mm in length, basally thickened, gradually narrowing toward apex, with a few loops; trunk of conductive tissue not pronounced (or possibly dissolved).

Measurements [mm; JJ (n = 10) / ♀♀ (n = 10), holotype in parentheses]. Body length 3.50–4.18 (3.75) / 3.50– 4.08; head length (excl. neck) 0.47–0.50 (0.47) / 0.48–0.55; head width across eyes 0.47–0.54 (0.54) / 0.48–0.53; vertex width 0.24–0.27 (0.26) / 0.28–0.30; length of antennal segments I – 0.15–0.18 (0.17) / 0.16–0.19, II – 0.48–0.56 (0.55) / 0.47–0.53, III – 0.32–0.39 (0.36) / 0.32–0.38, and IV – 0.39–0.42 (0.41) / 0.37–0.41; length of labial segments II – 0.12–0.16 (0.12) / 0.13–0.17, III – 0.54–0.62 (0.60) / 0.58–0.65, and IV – 0.30–0.35 (0.33) / 0.32–0.38; anterior pronotal width 0.36–0.41 (0.40) / 0.39–0.45; mesal pronotal length 0.51–0.57 (0.55) / 0.55–0.62; basal pronotal width 0.92–1.13 (1.04) / 0.99–1.17; length of embolial margin 0.91–1.15 (1.03) / 0.97–1.13; length of cuneal margin 0.65–0.80 (0.70) / 0.64–0.78; maximum width across hemelytra 0.96–1.18 (1.07) / 1.05–1.26.

Etymology. From Latin, venustus (= beautiful, graceful), referring to the beautiful and graceful body color of the new species; an adjective.

Bionomics. Anthocoris venustus sp. nov. has been frequently collected from Salix spp. in Hokkaido and Tochigi. It was also collected from Quercus crispula Blume , Kalopanax sp. , and Alnus japonica , and sometimes from the herbaceous plant Fallopia sachalinensis (F. Schmidt) Ronse Decr. in Hokkaido. This species was collected from Mallotus japonicus in Tokushima and from Quercus serrata Murray at Mt. Hikosan, Fukuoka (TൺKൾඇඈ 1998).

Distribution. Japan: Hokkaido, Rebun-tô Is., Rishiri-tô Is.; Honshu: Aomori, Iwate, Tochigi, Nagano, Gifu, Aichi, Nara; Shikoku: Tokushima, Ehime, Kochi; Kyushu: Fukuoka, Oita, Miyazaki ( Fig. 22 ). Compared to the distribution pattern of A. miyamotoi , the new species is widely distributed throughout Hokkaido and is restricted to the mountainous areas of Honshu, Shikoku, and Kyushu ( Fig. 22 ). This species shows an apparently allopatric distribution with A. miyamotoi . The allopatric distribution in both species might be influenced by differences in life history traits such as diapause and cold tolerance.

Figures

Fig. 8. Habitus of Anthocoris spp., male, dorsal (A, C–E, G–H) and lateral (B, F) views. A–B – A. miyamotoi Hiura, 1959, holotype (Nakanoshima Is., Tokara Isls.); C – same (Wakayama, Honshu); D – same (Kagoshima, Kyushu); E–F – A. venustus sp. nov., holotype (Hokkaido); G – same, paratype (Tochigi, Honshu); H – same, paratype (Nara, Honshu). Scale bars: 1.0 mm.

Fig. 9. Scanning electron micrographs of ostiolar peritreme and evaporatorium of Anthocoris spp, left lateroventral view. A – A. chibi Hiura, 1959, female; B – A. confusus Reuter, 1884, male (from India); C – A. japonicus Poppius, 1909, female; D – A. kalopanacis Kerzhner, 1977, female; E – A. takahashii Hiura, 1959, female; F – A. miyamotoi Hiura, 1959, female; G – A. venustus sp. nov., paratype, male. Abbreviations: eva ‒ evaporatorium; mf ‒ median furrow; op ‒ ostiolar peritreme; sca ‒ supracoxal area.

Fig. 11. Scanning electron micrographs of male genitalia of Anthocoris spp. A–B – A. miyamotoi Hiura, 1959; C–D – A. venustus sp. nov., paratype. A, C – pygophore with paramere, dorsal (A) and lateral (C) views; B, D – paramere, dorsal (B) and lateral (D) views. Abbreviations: prm ‒ paramere; pyg ‒ pygophore.

Fig. 12. Abdominal sterna II–III of Anthocoris spp., male, ventral view (setae omitted). A – A. chibi Hiura, 1959; B – A. confusus Reuter, 1884; C – A. japonicus Poppius, 1909; D – A. nemoralis (Fabricius, 1794); E – A. takahashii Hiura, 1959; F – A. miyamotoi Hiura, 1959; G – A. venustus sp. nov., paratype. Abbreviations: ma ‒ membranous area; st2–3 ‒ abdominal sternum II to III. Scale bars: 0.2 mm.

Fig. 14. Male genitalia of Anthocoris spp.A–C – A. miyamotoi Hiura, 1959; D–F – A. venustus sp. nov., paratype.A, D – pygophore with paramere (ejaculatory bulb omitted), dorsal view; B–C, E–F – paramere, two different views.Abbreviations: prm ‒ paramere; pyg ‒ pygophore. Scale bars: 0.1 mm.

Fig. 15. Female genitalia of Anthocoris spp., dorsal view.A – A. chibi Hiura, 1959; B – A. confusus Reuter, 1884; C – A. japonicus Poppius, 1909; D – A. nemoralis (Fabricius,1794); E – A.takahashii Hiura, 1959; F – A. miyamotoi Hiura, 1959; G – A. venustus sp. nov., paratype.Abbreviations: ct ‒ copulatory tube; ism ‒ intersegmental membrane; sp ‒ sperm pouch; t ‒ trunk of conductive tissue (C–D, trunk of conductive tissue dissolved). Scale bars: 0.1 mm.

Fig. 16. Habitus images of living individuals of Japanese Anthocorini spp. A – Acompocoris brevirostris Kerzhner, 1979, male; B – same, female; C – Tetraphleps aterrima (J. Sahlberg, 1878); D – Anthocoris confusus Reuter, 1884; E – A. takahashii Hiura, 1959; F – A. venustus sp. nov. (courtesy of M. Takai).

Fig. 22. Distribution of Anthocoris miyamotoi Hiura, 1959 (circles) and A. venustus sp. nov. (triangles) in Japan. Filled symbols represent records based on specimens examined by us, open symbols represent literature records.