Opistoplatys flavolineatus, Ishikawa, Tadashi, Cai, Wanzhi & Tomokuni, Masaaki, 2015

Ishikawa, Tadashi, Cai, Wanzhi & Tomokuni, Masaaki, 2015, The assassin bug subfamily Tribelocephalinae (Hemiptera: Heteroptera: Reduviidae) from Japan, with descriptions of eight new species in the genera Opistoplatys and Abelocephala, Zootaxa 3936 (2), pp. 151-180 : 156-160

Opistoplatys flavolineatus sp. nov.

( Figs. 5 , 10, 11 , 18–20 , 22 , 25–28 , 31, 32 , 36–38)

Diagnosis. This species is recognized by the following combination of character states: body brownish, approximately 7.6 mm long; head a little more than twice as long as width across eyes and approximately 1.5 times longer than pronotum; anteoculus 1.8 times longer than postoculus in male; eye approximately 3 times wider than interocular space in dorsal view in male; anterior pronotal lobe 0.45 times as long as posterior lobe along midline; and posterior pronotal lobe with yellowish longitudinal stripe along meson.

Description. Male. Body ( Fig. 5 ) mostly brown. Antennae and femora yellowish brown. Rostrum, tibiae, and tarsi brownish yellow. Posterior pronotal lobe yellowish brown on disc and humeral angles, with yellowish longitudinal stripe along meson ( Fig. 5 ). Hemelytra dark brown to blackish, with extreme base, corial veins, and basal halves of veins on membranes brownish yellow. Abdomen yellowish brown to dark brown.

Head ( Figs. 10, 11 ) a little more than twice as long as width across eyes, approximately 1.5 times longer than pronotum; anteoculus 1.8 times longer than postoculus, a little longer than width across antenniferous tubercles; postoculus 0.7 times as long as its maximum width. Eye ( Figs. 10, 11 ) approximately 3 times wider than interocular space in dorsal view. Antennal segment I slender, 0.9 times as long as segment II ( Figs. 18, 19 ), 1.8 times longer than anteoculus ( Fig. 5 ); flagellum ( Fig. 20 ) as long as segment I, slightly shorter than segment II. Rostral segment I 1.3 times longer than segment II ( Fig. 11 ).

Pronotum ( Fig. 10 ) approximately 0.7 times as long as humeral width; anterior lobe 0.45 times as long as posterior lobe along midline. Hemelytra ( Fig. 5 ) reaching or slightly exceeding apex of abdomen.

Abdomen 1.7 times longer than its maximum width, covered with suberect and decumbent setae, with posterior margin of segment VII slightly concave at middle ( Fig. 22 ). Pygophore ( Fig. 25 ) somewhat compressed dorsoventrally; posterior process ( Figs. 26–28 ) various in thickness in lateral view, gently curved posteriorly at base, finely rugose ventrally, at blunt apex in lateral view. Parameres ( Figs. 31, 32 ) evenly curved, weakly expanded inwardly at middle, at obtuse apex in dorsal view. Phallosoma of phallus (Figs. 36, 37) compressed dorsoventrally, sclerotized laterally, strongly extended laterad at base; struts (Fig. 38) fused in apical half, rounded apically in dorsal view.

Female. Unknown.

FIGURES 33–38. Phallus (33, 34, 36, 37) and struts (35, 38) of Opistoplatys minimus (33–35) and O. flavolineatus (36–38), lateral (33, 36) and ventral (34, 35, 37, 38) views. Abbreviation: st, struts. Scale bars: 0.2 mm (31, 32, 34, 35); 0.1 mm (33, 36).

Measurements [in mm, ♂ (n=27), holotype in parentheses]. Body length 6.92–8.20 (8.13). Head length 1.56–1.79 (1.77), width across eyes 0.72–0.84 (0.84). Lengths of antennal segments I and II 1.28–1.51 (1.50) and 1.36–1.61 (1.60), respectively. Lengths of rostral segments I and II 0.94–1.05 (1.05) and 0.78–0.84 (0.84), respectively. Pronotum length 0.98–1.19 (1.19), width across humeri 1.56–1.80 (1.77). Hemelytron length 4.85–5.70 (5.57). Lengths of femur and tibia of fore leg 1.67–1.98 (1.98) and 1.62–1.90 (1.90); of mid leg 1.61–1.92 (1.92) and 1.62–1.92 (1.92); of hind leg 2.22–2.57 (2.57) and 2.38–2.74 (2.74). Abdomen length 4.00–4.83(4.70), maximum width 2.41–2.92 (2.82).

Holotype. ♂ ( Fig. 5 ), “[ JAPAN] Aha, Kunigami-son, Okinawa-hontô Is., the Ryûkyûs, 21. IV. 2003, by box light trap, M. Kimura et al.” ( LETUA IC 2014-00042) ( TUA).

Paratypes (26 ♂). JAPAN [Okinawa Is.] Miyagi, Higashi-son: 6 ♂ (one shown in Figs. 25, 26 , 31, 32 , 36–38), 20.iv.2003, BLT, M. Kimura et al. ( LETUA IC 2014-00043–00048) ( TUA, CUA, NSMT), 1 ♂, 28.vi.2003, M. Kimura et al. ( LETUA IC 2014-00049) ( TUA). Takae, Higashi-son: 1 ♂, 17.iv.2003, BLT, M. Kimura et al. ( LETUA IC 2014-00050) ( TUA), 5 ♂ (one shown in Figs. 18–20 ), 18.iv.2003, BLT, M. Kimura et al. ( LETUA IC 2014-00051–00055) ( TUA), 1 ♂, 4.vii.2003, BLT, M. Kimura ( LETUA IC 2014-00056) ( TUA). Aha, Kunigamison: 1 ♂ ( Figs. 10, 11 ), 20.iv.2003, BLT, M. Kimura et al. ( LETUA IC 2014-00057) ( TUA), 6 ♂ (one shown in Figs. 22 , 27 ), same data as holotype ( LETUA IC 2014-00058–00063) ( TUA, CAU), 1 ♂, 2.vii.2003, BLT, M. Kimura ( LETUA IC 2014-00064) ( TUA), 1 ♂, 2.vii.2003, M. Kimura et al. ( LETUA IC 2014-00065) ( TUA), 1 ♂, 5.vii.2003, BLT, M. Kimura ( LETUA IC 2014-00066) ( TUA), 1 ♂, 15.vii.2003, M. Kimura et al. ( LETUA IC 2014-00067) ( TUA). Yona, Kunigami-son: 1 ♂, 2.vi.1966, S. Tachikawa ( LETUA IC 2014-00068) ( TUA).

Other specimens examined. JAPAN [Amami-Oshima Is.] Shinokawa, Setouchi-chô: 2 ♂ (one shown in Fig. 28 ), 23.vi.1997, S. Yoshimichi ( TUA).

Distribution. Japan: Ryukyu Islands (Amami-Oshima Is., Okinawa Is.).

Etymology. From the Latin compound flavolineatus , referring to the yellowish longitudinal stripe on the posterior pronotal lobe; an adjective.

Remarks. The yellowish longitudinal stripe on the posterior pronotal lobe is sometimes indistinct or reduced to spot-like. In general appearance, this new species closely resembles O. minimus sp. nov. However, O. flavolineatus sp. nov. can be distinguished from O. minimus sp. nov. by its relatively large body length (approximately 7.6 mm vs. approximately 6.7 mm), antennal flagellum shorter than antennal segment II ( Figs. 19, 20 ) [vs. longer than antennal segment II ( Figs. 13, 14 )], yellowish longitudinal stripe along the meson of the posterior pronotal lobe ( Fig. 5 ) [vs. no such stripe ( Figs. 3, 4 )], and parameres weakly expanded inwardly at the middle ( Fig. 32 ) [vs. not expanded inwardly at the middle ( Fig. 30 )].

Almost all of the specimens examined in the present study were collected during April to July by using BLTs placed on trees in the forests of Okinawa Island. No additional information regarding the biology of this reduviid is available.

Figures

FIGURES 3 – 5. Opistoplatys spp., habitus in dorsal view. 3 – 4, O. minimus, male (3) and female (4); 5, O. flavolineatus, male. Scale bars: 2 mm.

FIGURES 6 – 11. Head and pronotum (6, 10) and head (7 – 9, 11) of Opistoplatys spp., dorsal (6, 8, 10) and lateral (7, 9, 11) views. 6 – 9, O. minimus, male (6, 7) and female (8, 9); 10, 11, O. flavolineatus, male. Scale bar: 1 mm.

FIGURES 12 – 20. Left antenna of Opistoplatys minimus (12 – 17) and O. flavolineatus (18 – 20), dorsal view, setae omitted. 12 – 14, 18 – 20, male; 15 – 17, female. 12, 15, 18, segment I; 13, 16, 19, segment II; 14, 17, 20, flagellum. Scale bars: 0.5 mm.

FIGURES 21 – 22. Apical part of male abdomen of Opistoplatys minimus (21) and O. flavolineatus (22), ventral view, pygophore removed and setae omitted. Scale bar: 1 mm.

FIGURES 23 – 28. Pygophore (23, 25) and posterior process (24, 26 – 28) of Opistoplatys minimus (23, 24) and O. flavolineatus (25 – 28), lateral view, setae omitted. Scale bars: 0.2 mm (23, 25); 0.05 mm (24, 26 – 28).

FIGURES 29 – 32. Paramere of Opistoplatys minimus (29, 30) and O. flavolineatus (31, 32), ventrolateral (29, 31) and dorsal (30, 32) views. Scale bar: 0.2 mm.