Acanthosoma, Curtis, 1824

Tsai, Jing-Fu & Rédei, Dávid, 2015, The genus Acanthosoma in Taiwan (Hemiptera: Heteroptera: Acanthosomatidae), Acta Entomologica Musei Nationalis Pragae 55 (2), pp. 625-664 : 627-629

publication ID	https://doi.org/ 10.5281/zenodo.5303571
publication LSID	lsid:zoobank.org:pub:0360453D-E09E-4CC4-9BB0-981AEC7BED66S
DOI	https://doi.org/10.5281/zenodo.5331593
persistent identifier	https://treatment.plazi.org/id/03B63F65-9F58-1C4D-FEEB-FD19FBC6FC07
treatment provided by	Marcus
scientific name	Acanthosoma
status

Treatment

Key to the species of Acanthosoma View in CoL occurring in Taiwan

1 Humeri rounded, slightly surpassing costal margins of fore wing laterally. ................ 2

– Humeri produced into distinct processes of various length ( Figs 56–91 View Figs 56–59 View Figs 60–63 View Figs 64–67 View Figs 68–71 View Figs 72–75 View Figs 76–79 View Figs 80–83 View Figs 84–87 View Figs 88–91 ). ................... 3

2 Body large (17.5–19.5 mm). Posterolateral angle of pronotum provided with a small, triangular process directed posteriad and extending over base of corium. Black markings of connexival plates enclosing intersegmental sutures broad (as wide as or wider than tibia). Genital capsule of male large, robust, with short, broad, apically rounded lateral projections not surpassing apex of membrane, ventrally densely pilose, provided with 1+1 pigmented denticles subapically and 1+1 denticles proximally. Posterior margin of laterotergites VIII of female broadly rounded, ventrites VI and VII each with a pair of large Pendergrast’s organs. ............................ A. crassicaudum Jakovlev, 1880 View in CoL

– Body of medium size (14.5–16.5 mm). Posterolateral angle of pronotum without small triangular process. Black markings of connexival plates enclosing intersegmental sutures narrow (narrower than tibia). Genital capsule of male provided with a pair of long, slender, posteriorly strongly diverging posterolateral projections, apical halves of projections surpass apex of membrane, ventral surface lacking pigmented denticles. Posterior margin of laterotergite VIII of female truncate, ventrites VI and VII each with a pair of small Pendergrast’s organs. .................................. A. forficula Jakovlev, 1880 View in CoL

3 Posterolateral angles of pregenital abdominal ventrites not produced ( Fig. 16 View Figs 11–19 ). Posterolateral angle of pronotum horizontal, subtriangularly produced and broadly obtuse apically (population in Japan and the Asian mainland) or elevated, finger-shaped, with rounded apex (population in Taiwan), in both cases with black punctures nearly to their tip ( Figs 86–91 View Figs 84–87 View Figs 88–91 ). Genital capsule of male without lateral projection, subquadrate in posterior view, ventral rim with 1+1 pigmented denticles laterally ( Figs 16–19 View Figs 11–19 ). Ventrite VII of female with 1+1 small, black, rounded spots laterad of median incision of posterior margin, Pendergrast’s organs on ventrites VI and VII narrowly separated ( Fig. 55 View Figs 52–55 ). ................................................................................... A. expansum Horváth, 1905 View in CoL

– Posterolateral angles of abdominal ventrites II–VI produced into small, sharp denticles (as in Figs 1, 6, 8 View Figs 1–10 , 15 View Figs 11–19 , 45–46, 48–55 View Figs 45–51 View Figs 52–55 ). .......................................................................... 4

4 Connexivum uniformly pale. ....................................................................................... 5

– Connexival plates with conspicuous black markings anteriorly and posteriorly, enclosing intersegmental sutures. ......................................................................................... 10

5 Head unpunctured or at most with very few punctures which are pale, never contrasting black. ............................................................................................................................ 6

– Head with irregularly distributed black punctures on mandibular plates and between eyes. ............................................................................................................................. 7

6 Body very large (16.5–20.7 mm) ( Figs 80–83 View Figs 80–83 , 92–93 View Figs 92–99 ). Genital capsule of male with a pair of robust, apically rather acute posterolateral projections, with 2+2 denticles on dorsal rim due to extension of dorsal wall over ventral infolding, and 1+1 of protuberances on ventral rim laterally ( Fig. 15 View Figs 11–19 ). Paramere as in Figs 40–41 View Figs 20–44 . Posterior margin of laterotergites VIII of female truncate, reaching or slightly surpassing posterolateral angles of ventrite VII; Pendergrast’s organs of ventrite VII larger (diameter more than 0.5 mm) ( Fig. 54 View Figs 52–55 ). ............................................................... A. laevicorne Dallas, 1851 View in CoL

– Body relatively small (13.8–16.5 mm) ( Figs 84–85 View Figs 84–87 ). Genital capsule of male with a pair of short posterolateral projections, dorsal rim broadly U-shaped, apex of paramere bifurcated. Posterior margin of laterotergites VIII of female broadly rounded, far surpassing posterolateral angles of ventrite VII, posterior margin of ventrite VII with a deep, U-shaped incision margined with black; Pendergrast’s organ of ventrite VI small (diameter less than 0.5 mm). ............................................. A. sichuanense ( Liu, 1980) View in CoL

7 Humeral process long, directed distinctly anterolaterad, apically sharp ( Figs 60–63 View Figs 60–63 , 72–75 View Figs 72–75 ). ......................................................................................................................... 8

– Humeral process short, directed laterad, apically sharp ( Figs 68–71 View Figs 68–71 ) or obtuse ( Figs 56–59 View Figs 56–59 ). ......................................................................................................................... 9

8 Humeral process bright red ( Figs 60–63 View Figs 60–63 ). Head punctured, interocular area with a pair of longitudinal rows of black punctures, maxillary plate without tubercle. ................... .................................................................. A. haemorroidale formosanum subsp. nov.

– Humeral process black or brownish ( Figs 72–75 View Figs 72–75 ). Head with very few and faint punctures, interocular area without longitudinal rows of black punctures, maxillary plate with a conspicuous, obtuse tubercle anteriad and mesad of antennal insertion. ............. .......................................................................................................... A. pugnax sp. nov.

9 Maxillary plate without tubercle. Humeral process short and broad, subtriangular, apically obtuse, reddish brown to red with more or less distinct dark suffusion ( Figs 56– 59 View Figs 56–59 ). Genital capsule of male with a pair of short and broad posterolateral projections, dorsal rim broadly U-shaped, greatly covered by membrane ( Figs 1–3 View Figs 1–10 ). Posterior margin of laterotergites VIII of female strongly protruding; Pendergrast’s organ on ventrite VII of female small ( Fig. 45 View Figs 45–51 ). ........................................................... A. atayal sp. nov.

– Maxillary plate with a conspicuous, obtuse tubercle anteriad and mesad of antennal insertion. Humeral process spiniform, directed laterad, yellow to pale orange ( Figs 68– 71 View Figs 68–71 ). Genital capsule with a pair of elongate, gracile, arched posterolateral projections far surpassing apex of membrane, dorsal rim narrowly U-shaped, concave at midline ( Figs 8–9 View Figs 1–10 ). Posterior margin of tergite VIII of female truncate, not surpassing posterolateral angles of abdominal segment VII; Pendergrast’s organs of ventrites VI and VII of female elliptical, of equal size ( Fig. 51 View Figs 45–51 ). ....................................... A. fallax sp. nov.

10 Head with irregularly distributed black punctures on mandibular plates and between eyes. Hind tibia of male dilated subbasally ( Fig. 47 View Figs 45–51 ). Genital capsule of male with a pair of long, subparallel posterolateral projections ( Figs 6–7 View Figs 1–10 ). Posterior margin of tergite VIII of female prominent, far surpassing posterolateral angles of segment VII ( Fig. 48–49 View Figs 45–51 ). ................................................................................ A. asahinai Ishihara, 1943 View in CoL

– Head unpunctured or at most with very few punctures which are pale, never contrasting black. Hind tibia of male not dilated. ......................................................................... 11

11 Humeral process relatively long, directed laterad (population in Taiwan) or more or less anterolaterad (population in Japan and the Asian mainland), frequently red. Male genital capsule with a robust, apically obtusely rounded posterolateral projections not surpassing apex of membrane, widely separated by a broad median incision, ventral rim broadly excavate, of rather rectangular outline, densely pilose, with a pair of small, pigmented denticles. Posterior margin of ventrite VII of female with a pentagonal median incision; Pendergrast’s organs of ventrites VI and VII small (diameter less than 0.5 mm), rather broadly separated. ......................................... A. firmatum ( Walker, 1868) View in CoL

– Humeral process short, invariably directed laterad, yellow to pale orange, never red ( Figs 76–79 View Figs 76–79 ). Male genital capsule with a pair of scissors-like posterolateral projections surpassing apex of membrane by their apical halves, dorsal rim nearly V-shaped, ventral surface densely covered by long setae ( Figs 11–14 View Figs 11–19 ). Posterior margin of ventrite VII of female with a shield-shaped median incision; Pendergrast’s organs of ventrites VI and VII large (diameter more than 0.5 mm), narrowly separated ( Fig. 52 View Figs 52–55 ). .............. ............................................................................................................ A. axicia sp. nov.