The assassin bug subfamily Tribelocephalinae (Hemiptera: Heteroptera: Reduviidae) from Japan, with descriptions of eight new species in the genera Opistoplatys and Abelocephala Author Ishikawa, Tadashi Author Cai, Wanzhi Author Tomokuni, Masaaki text Zootaxa 2015 3936 2 151 180 journal article 10.11646/zootaxa.3936.2.1 e202312c-4686-47ed-bbd2-d470a62d5e4a 1175-5326 241991 157EDA4A-00A3-469F-8234-7E7175BF13E7 Abelocephala yaeyamensis sp. nov. ( Figs. 47, 48 , 59, 60 , 68 , 73 , 79 , 99–104 , 117 , 123 , 129, 135, 141, 147, 152) Diagnosis. This species is recognized by the following combination of character states: body length approximately 4 mm in male and 5 mm in female; mandibular plate acutely angled at anterior corner and strongly projected anteriorly in dorsal view; rostral segment I approximately twice as long as segment II; posterior pronotal lobe pale brownish yellow; outer (larger) cell of hemelytral membrane acutely angled apically; and posterior process of pygophore narrow with rounded apical margin in dorsal view. FIGURES 59–64. Head (59, 61, 63) and anteoculus (60, 62, 64) of Abelocephala spp., male, dorsal view, antennae removed. 59, 60, A . yaeyamensis ; 61, 62, A . major ; 63, 64, A . longiceps . Abbreviation: mp, mandibular plate. Scale bars: 0.2 mm (59, 61, 63); 0.1 mm (60, 62, 64). Description. Male (macropterous) . Body ( Fig. 47 ) mostly brownish. Antennae, rostrum, and legs brownish yellow. Antennal flagella pale yellow. Posterior pronotal lobe pale brownish yellow except for median longitudinal sulcus and posterior marginal area brown. Hemelytra dark brown, with corial veins yellowish brown. Abdomen yellowish brown to brown. Head ( Figs. 47 , 59, 60 , 73 ) approximately 1.4 times longer than width across eyes, 0.9 times as long as pronotum, roundly protuberant immediately behind eyes in dorsal view; anteoculus 1.2 times longer than postoculus; mandibular plate ( Fig. 60 ) acutely angled at anterior corner and strongly projected anteriorly in dorsal view. Eye ( Figs. 59 , 73 ) approximately half as wide as interocular space in dorsal view. Antennal segment I slender, approximately 9 times longer than its maximum width, as long as segment II ( Figs. 99, 100 ); flagellum 0.85 times as long as segment I ( Fig. 101 ). Rostral segment I slender, approximately twice as long as segment II ( Fig. 73 ). Pronotum ( Fig. 47 ) approximately 0.8 times as long as humeral width; anterior lobe 0.55 times as long as posterior lobe along midline, 0.75 times as wide as humeral width. Hemelytron ( Figs. 47 , 117 ) wide, 2.2 times longer than its maximum width, exceeding apex of abdomen by approximately 0.3 times of its length; outer (larger) cell of membrane ( Fig. 117 ) acutely angled apically. Pygophore ( Fig. 123 ) elliptical in lateral view; posterior process (Fig. 129) narrow, with rounded apical margin in dorsal view. Parameres ( Fig. 135 ) strongly curved in apical two-thirds, with rounded, inwardly projected apex in dorsal view. Struts of phallus ( Fig. 141 ) tapering apicad, weakly constricted at apical one-third, rounded at apex, and with lateral walls thickened in basal half in dorsal view. Female (micropterous) . At first glance, quite different from male due to micropterous condition ( Fig. 48 ). Head ( Figs. 48 , 68 , 79 ) approximately 1.5 times longer than width across eyes, 1.2 times longer than pronotum. Eye ( Figs. 68 , 79 ) small, approximately 0.25 times as wide as interocular space in dorsal view. Antennal segment I much stouter than that of male, approximately 5 times longer than its maximum width, as long as segment II ( Figs. 102, 103 ); flagellum 1.1 times longer than segment I ( Fig. 104 ). Pronotum ( Fig. 48 ) approximately 0.9 times as long as humeral width; anterior lobe 1.3 times longer than posterior lobe along midline, 1.05 times wider than humeral width. Hemelytra ( Fig. 48 ) small, pad-like, reaching to middle of abdominal tergite III; venation inconspicuous. Abdominal tergite IX ( Fig. 147 ) with lateral projection at each basal angle; lateral projection short, narrowed in apical part, obtuse at apex. Valvifer I ( Fig. 152 ) oblong; valvula I ( Fig. 152 ) with 4 setae. FIGURES 65–69. Head of Abelocephala spp., female, dorsal view, antennae removed. 65, A . albula ; 66, A . araiorum ; 67, A . nakatai ; 68, A . yaeyamensis ; 69, A . major . Scale bars: 0.2 mm. Measurements [in mm, ♂ (n=33) /♀ (n=2), holotype in parentheses]. Body length 3.88–4.58/4.67–5.18 (4.40). Head length 0.84–0.95/1.08–1.19 (0.95), width across eyes 0.68–0.74/0.72–0.81 (0.73). Lengths of antennal segments I and II 1.03–1.18/0.82–0.85 (1.18) and 1.02–1.14/0.80–0.83 (1.14). Lengths of rostral segments I and II 0.73–0.78/0.85–0.91 (0.78) and 0.36–0.37/0.42–0.43 (0.37). Pronotum length 0.92–1.05/1.01–1.04 (1.05), width across humeri 1.21–1.37/1.03–1.09 (1.37). Hemelytron length 3.58–3.95/0.96–1.05 (3.90). Lengths of femur and tibia of fore leg 1.09–1.27/1.22–1.28 (1.27) and 1.19–1.35/1.26–1.31 (1.35); of mid leg 1.12–1.26/1.22–1.27 (1.26) and 1.15–1.37/1.30–1.32 (1.37); of hind leg 1.50–1.72/1.70–1.72 (1.72) and 1.62–1.94/1.68–1.72 (1.94). Abdomen length 2.05–2.40/2.70–2.92 (2.39), maximum width 1.73–1.94/2.48–2.55 (1.93). Holotype . ♂ ( Fig. 47 ), “[ JAPAN ] Shirahama, Iriomote-jima Is., the Ryûkyûs, 23–27.IV.2004 , FIT, T. Ishikawa et al.” ( LETUA IC 2014-00185) ( TUA ). Paratypes ( 32 ♂ , 2 ♀). JAPAN [Ishigaki Is.] Mt. Yarabu-dake: 1 ♂ , 23–24.v.2001 , FIT-M, T. Shimada ( LETUA IC 2014-00186) ( TUA ). Shiramizu: 1 ♂ , 3–6.v.2004 , FIT-M, T. Ishikawa ( LETUA IC 2014-00187) ( TUA ). Takeda-rindô: 1 ♂ ( Fig. 117 ), 10.vi.2003 , S. Nagashima ( LETUA IC 2014-00188) ( TUA ). Mt. Omotodake: 1 ♂ , 1–12.vii.2002 , FIT-M, T. Nakata ( LETUA IC 2014-00189) ( TUA ). Mt. Nosoko-dake: 1 ♂ , 10.vi.2003 , T. Ishikawa ( LETUA IC 2014-00190) ( TUA ). [Iriomote Is.] Ôtomi-rindô: 1 ♂ , 7–11.vi.2002 , Malaise trap, T. Tsuru ( LETUA IC 2014-00191) ( TUA ). Komi: 1 ♀ ( Figs. 48 , 68 , 79 , 102 –104), 2.iii.2002 , T. Ishikawa ( LETUA IC 2014-00192) ( TUA ), 12 ♂ (one shown in Figs. 59, 60 , 73 , 99–101 ), 23–27.iv.2004 , FIT-M, T. Ishikawa et al . ( LETUA IC 2014-00193–00204) ( TUA , CAU , NSMT ), 3 ♂ , 8–12.x.2004 , T. Ishikawa et al . ( LETUA IC 2014- 00205–00207) ( TUA ), 3 ♂ , 7–11.iv.2005 , FIT-M, J. Kantoh ( LETUA IC 2014-00208–00210) ( TUA ). Aira-gawa Riv.: 1 ♂ , 24.v.1999 , S. Inada ( LETUA IC 2014-00211) ( TUA ), 1 ♂ , 28.iv.2003 , T. Kurihara ( LETUA IC 2014- 00212) ( TUA ), 1 ♂ , 2.v.2003 , T. Kurihara ( LETUA IC 2014-00213) ( TUA ). near Yuchin-gawa Riv.: 2 ♂ , 11–13.ix.2003 , K. & S. Arai ( LETUA IC 2014-00214–00215) ( TUA ). Kanpira-no-taki: 1 ♀ ( Figs. 147 , 152 ), 2.v.1999 , S. Arai & K. Toyoda ( LETUA IC 2014-00216) ( TUA ). Shirahama: 3 ♂ (one shown in Figs. 123 , 129, 135, 141), same data as holotype ( LETUA IC 2014-00217–00219) ( TUA ). Distribution. Japan : Ryukyu Islands (Ishigaki Is., Iriomote Is.). Etymology. Based on the name of the island group that includes Ishigaki Island and Iriomote Island; an adjective. Remarks. Macropterous males and micropterous females of this species are known. In general appearance, this new species resembles A . albula sp. nov. However, A . yaeyamensis sp. nov. is distinguished from A . albula sp. nov. by its larger body ( 3.8–5.2 mm vs. 2.7–3.2 mm ), the mandibular plate acutely angled at the anterior corner and strongly projected anteriorly in dorsal view ( Fig. 60 ) [vs. nearly right-angled at the anterior corner and weakly projected anteriorly in dorsal view ( Fig. 54 )], rostral segment I approximately twice as long as segment II ( Figs. 73 , 79 ) [vs. 1.4–1.5 times longer than segment II ( Figs. 70 , 76 )], and the posterior process of the pygophore narrow with a rounded apical margin in dorsal view (Fig. 129) [vs. wide with a straight apical margin in dorsal view (Fig. 126)]. Most specimens (15 individual) of A . yaeyamensis sp. nov. were collected from FIT-Ms placed in Komi, Iriomote Island. This new species was found simultaneously with A . albula sp. nov. and A . nakatai sp. nov. This observation implies that these three species sympatrically inhabit leaf litter of moist forests in the Yaeyama group of the Ryukyu Islands.