Acanthosoma atayal, Tsai & Rédei, 2015

Tsai, Jing-Fu & Rédei, Dávid, 2015, The genus Acanthosoma in Taiwan (Hemiptera: Heteroptera: Acanthosomatidae), Acta Entomologica Musei Nationalis Pragae 55 (2), pp. 625-664 : 629-631

Acanthosoma atayal sp. nov.

( Figs 1–3 , 20–21 , 45 , 56–59 )

Type material. HOLOTYPE: J, TAIWAN: NANTOU CO.: Yuanfeng, Provincial Rd. No. 14A 22.5K, 15.x.2010, ex. Photinia niitakayamensis Hayata , leg. S.W. Hou; mounted on card, intact, deposited in NMNS ( Figs 56–57 ). PARA- TYPES: TAIWAN: TAIPEI CO.: Wulai , 15.x.2008, leg. C.B. Sun (1 J [dissected] NTU). TAICHUNG CO.: Anmasan , 18.vii.1983, leg. C.L. Chen (1 ♀ NCHU). NANTOU CO.: same as holotype (1 J 1 ♀ NMNS); same as holotype, ex Cyclobalanopsis stenophylloides (Hayata) Kudo & Masamune ex Kudo (1 J NCHU); Yuanfeng , Provincial Rd. No. 14A, 24.5K, 1.x.2010, ex Photinia niitakayamensis Hayata , leg. S.W. Hou (1 J 1 ♀ NCHU); Yuanfeng , Provincial Rd. No. 14A, 24.5K, 1.x.2010, ex Photinia niitakayamensis Hayata , leg. S.W. Hou (1 J 1 ♀ HNHM, 1 J 1 ♀ NMPC, 1 J TFRI); Ho Huan Shan , 26.vii.1990, sweeping, leg. W.C. Chuang, NMNS ENT 639-546 (1 ♀ NMNS); Sun Moon Lake , Yuchih env., Puli, 12–16.vi.1995, leg. J. Dalihod (1 J ZJPC); Tseifeng, 1.viii.1985, leg. H. Takizawa (2 ♀♀ SEHU). CHIAYI CO.: Alishan, 20.vi.1982, leg. K. Nagami, NMNT-I-He 34905 (1 ♀ NSMT). HUALIEN CO.: Tayuling, 2560 m, 12–15.ix.1980, leg. K.S. Lin & C.W. Wang (1 J TARI).

Diagnosis. The species can be recognized by its humeri being distinctly produced but relatively short and broad, apically obtuse, directed slightly posterolaterad, punctured, and tinged with reddish. The male ( Figs 1–3 ) and female ( Fig. 45 ) terminalia are diagnostic.

Description. Colour. Ground colour of dorsum green (turning to yellowish in dead specimens), suffused with reddish brown to various extent; pronotum broadly suffused with red on calli and along its posterior margin, humeral processes reddish brown to red with more or less distinct dark suffusion; endocorium of fore wings usually with strong ferruginous suffusion; abdomen pale yellow, with distinct red suffusion on exposed parts of segments VII (J, ♀), VIII (♀), and dorsal surface of genital capsule (J); connexival plates and corresponding ventrites of abdominal segments II–VII without black markings.

Integument and vestiture. Body glabrous except of fine, scattered hairs on appendages and terminalia; mandibular plates with a few scattered black punctures, interocular area with a pair of irregular longitudinal rows of black punctures; pronotum, scutellum and sclerotized parts of fore wings with rather uniform black punctation except on calli, distal portions of humeral processes and costal margin of fore wing, punctation of exocorium and neighbouring part of endocorium not conspicuously different; ventral surface of body virtually unpunctured except of scattered punctures on ventral surface of humeral process and faint, superficial punctures along posterior margin of abdominal ventrite VIII and on ventral surface of genital capsule of male.

Structure. Body elongate oval with distinctly produced humeri, distance between tips of humeral processes about 1.2–1.25 (J, ♀) times as long as greatest width of body posteriad of humeri. Head 1.2–1.25 (J, ♀) times as broad as its median length, about 1.55–1.6 times as broad as interocular distance, finely transversely rugose, anterior portion of clypeus depressed, with a broad median longitudinal groove. Labium slightly surpassing mid coxae. Pronotum with anterolateral margin weakly concave, continued in humeral processes without conspicuous break in its outline; humeri short and broad, subtriangular, directed subhorizontally, apically obtuse. Thoracic pleuron and sternum. Mesosternal carina distinctly surpassing base of head, highly elevated, rather broadly rounded anteriorly; metathoracic scent gland ostiole with a long, slightly arched peritreme.

Male and female terminalia. Male. Genital capsule ( Figs 1–3 ) with a pair of short posterolateral projections each with a dense tuft of setae apically; dorsal rim broadly U-shaped; ventral rim with a tuft of setae medially, ventral infolding densely pilose. Paramere ( Figs 20–21 ) L-shaped, apex finger-shaped. Female ( Fig. 45 ). Posterior margin with a deep, shield-shaped median incision surrounding valvifers VIII; posterior margin of laterotergites VIII prominent, far surpassing posterolateral angle of abdominal segment VII. Pendergrast’s organs on ventrites VI and VII broadly separeted, those on ventrite VII much smaller than those on ventrite VI.

Measurements (in mm). Body length from apex of head to apex of membrane 11.9–12.2 (J) / 13.7–14.9 (♀); greatest width of body posteriad of humeral processes 5.06–8.34; median length of head 1.75–1.95, width across eyes 2.15–2.40, interocular distance 1.35–1.55; length of antennal segments (I) 1.50–1.55: (IIa) 1.65–1.80: (IIb) 1.25–1.40: (III) 1.85–2.00: (IV) 1.80–1.85; median length of pronotum 2.00–2.75, greatest width (across tips of humeri) 6.41–8.49; median length of scutellum 3.45–4.45, width at base 2.85–3.70.

Etymology. The specific epithet is derived from the name of the Atayal people, one of Taiwan’s indigenous tribes residing in the mountainous regions of northern and central Taiwan where the new species occurs; noun in apposition, ending not to be changed.

Bionomics. Several specimens were collected in multiple occasions from Photinia niitakyamensis Hayata (Rosaceae) during its fruiting period. The breeding season of the species is around October. A few specimens were found on Cyclobalanopsis stenophylloides Kudô & Masam. (Fagaceae) .

Distribution. The species is endemic to Taiwan, apparently restricted to mountainous regions ranging from 1500 to 2500 m in altitude.

Remarks. This species belongs to the Acanthosoma haemorrhoidale species group hereby defined in the following way: posterolateral angles of genital capsule produced into a pair of short and broad projections but never into conspicuously elongate processes, of trapezoid shape in posterior view, ventral infolding perpendicular, facing posteriad in rest; paramere simple, rod-like, apex either rounded or hooked but never bifurcate. The group currently contains A. haemorrhoidale (Linnaeus, 1758) , A. emeiense Liu, 1980 , A. spinicolle Jakovlev, 1880 , A. nigrodorsum Hsiao & Liu, 1977 , A. murreeanum ( Distant, 1900) and the newly described A. atayal sp. nov. The new species differs from all of the previously described members of the species group in its relatively smaller and more slender body, the shape of its humeral processes, and the reduced Pendergrast’s organs on ventrite VII. It is particularly similar to A. haemorrhoidale ; besides of the above characters, it differs from the latter species in the angularly broken apical portion of the paramere ( Fig. 20 ) (strongly hooked in A. haemorrhoidale , cf. Figs 22–24 ) and the strongly convex posterior margin of laterotergites VIII of female (weakly convex in A. haemorrhoidale ).

Figures

Figs 1–10.Acanthosoma spp., males. 1 – A.atayal sp.nov., posterior part of abdomen, ventral view; 2 – same, genital capsule and exposed part of segment VIII, ventral view; 3 – same, genital capsule, lateral view; 4 – A. haemorrhoidale formosanum subsp. nov., holotype, genital capsule, posterior view; 5 – A.haemorrhoidale haemorrhoidale (Linnaeus, 1758) (Spain: Fuente Dé, HNHM), genital capsule, posterior view; 6 – A. asahinai Ishihara, 1943, posterior part of abdomen, ventral view; 7 – same, genital capsule, ventral view; 8 – A. fallax sp. nov., posterior part of abdomen, ventral view; 9 – same, genital capsule, ventral view; 10 – A. pugnax sp. nov., genital capsule and exposed part of segment VIII, ventral view. Scales in mm.

Figs 20–44. Acanthosoma spp., right parameres in different views. 20–21 – A. atayal sp. nov.; 22 – A. haemorrhoidale formosanum subsp. nov., holotype; 23 – A. haemorrhoidale ouchii Ishihara, 1950 (China: Sichuan, Mt. Emei, USNM); 24 – A. haemorrhoidale haemorrhoidale (Linnaeus, 1758) (Spain: Fuente Dé, HNHM); 25–28 – A. asahinai Ishihara, 1943; 29–32 – A. fallax sp. nov.; 33–36 – A. pugnax sp. nov.; 37–39 – A. axicia sp. nov.; 40–41 – A. laevicorne Dallas, 1851; 42–44 – A. expansum Horváth, 1905. Scales in mm.

Figs 45–51. Acanthosoma spp. 45 – A. atayal sp. nov., female terminalia, posteroventral view; 46 – A. haemorrhoidale formosanum subsp. nov., paratype, female terminalia, posteroventral view; 47 – A. asahinai Ishihara, 1943, hind tibia of male; 48 – same, female terminalia, dorsal view; 49 – same, posteroventral view; 50 – A. fallax sp. nov., female terminalia, dorsal view; 51 – same, posteroventral view. PO6, PO7 = Pendergrast’s organs of ventrites VI and VII, respectively. Scales in mm.

Figs 56–59. Acanthosoma atayal sp. nov. 56–57 – male; 58–59 – female. Scales in mm.