Stethoconus takaii, Nakatani, Yukinobu & Yasunaga, Tomohide, 2018

Nakatani, Yukinobu & Yasunaga, Tomohide, 2018, Two new deraeocorine plant bug species from Japan (Heteroptera, Miridae, Deraeocorinae), ZooKeys 796, pp. 163-174 : 163

Stethoconus takaii sp. n. Figs 7, 10-11, 13-14, 16, 18, 25-29, 32-37

Stethoconus japonicus : Yasunaga et al. 1997 (part), Nakatani and Yasunaga 2001 (part).

Type material.

Holotype: ♂. Japan: Shikoku, Kochi., Agawa, Ino, 33.56N, 133.39E, 2 Aug 1998, M. Takai (AMNH_PBI 00380593) (NIAES). Paratypes: [Honshu] 1♀, Shizuoka, Atami alt. 300m, 22 Jul 1996, T. Ueda (NIAES); 1♂, Gifu, Gujou, Yamatocho-uchigatani, 28-29 Sep 2004, T. Ueda (NIAES); 1♂, Mie, Mt. Hirakura, 23 Jun 1953, Y. Miwa (NIAES); 2♂, Osaka, Minoo, 21 Jul 1995, K. Temma (NIAES); 1♂, Hyogo, Inagawa, Tsukunami, at light, 12 Jun 1997, Y. Nakatani (NIAES); 1♂, Nara, Kawakami, Shionoha, at light, 15 Jun 1993, Y. Nakatani (NIAES); 6♂1♀, Nara, Kawakami, Kitamata, at light, 15 Jun 1993, Y. Nakatani (AMNH & NIAES); 2♂, Nara, Kamikitayama, Mt. Wasamata, at light, 9 Aug 1995, T. Hirowatari & Y. Sawada (NIAES); 1♂: Wakayama, Kumanogawa, Doro Valley, Tamakiguchi, 33°53'53"N, 135°52'23"E, 15 Jun 1993, S. Gotoh (AMNH_PBI 00380594) (TYCN); 1♂, Wakayama, Shingu, Shirami, 9 Sep 1999, K. Temma (NIAES). [Shikoku] 1♀, same data as for holotype (TYCN).

Diagnosis.

Coloration generally dark; antennal segment II, or at least basal and apical 1/3, darkened; areas between pronotal punctures rather smooth; scutellum weakly elevated and blackish; mesepimeron blackish; abdomen mostly blackish.

Description.

Body generally maculate; dorsum shiny, densely clothed with long erect yellowish setae. Head shiny yellowish brown; brown stripe on vertex. Antenna dark brown; basal 1/3 or half of segment I somewhat pale, sometimes tinged with red; middle portion of segment II sometimes pale; base of segment III pale. Labium yellowish brown except tip brown, reaching anterior margin of mesosternum. Pronotum dark brown with yellowish quotation mark-shaped markings, strongly convex and distinctly punctate, densely covered with long erect yellowish setae; collar yellowish brown with dark base punctate, length 0.56 of width; triangular yellowish marking on mesal calli; short longitudinal whitish stripe on base of disc; posterior margin narrowly pale; areas between punctures on disc somewhat swollen but not calloused; prosternum yellowish brown, conically projecting. Scutellum entirely dark, gradually elevated to posterior with rounded carinate process; meso- and metapleura dark except for ostiolar peritreme whitish yellow. Hemelytron smooth, shiny and transparent with two transverse brown bands; anterior 1/4 and posterior half dark brown; mesal half of posterior end of corium brown, both sides of marking connected with posterior transverse band; posterior part of embolium narrowly brown; posterior part of cuneus and membrane veins tinged with brown. Legs pale yellowish brown; hind femur with apical 1/3 brown or with red band. Abdomen almost entirely dark brown in male, lateral half of segments II, IV and VII yellowish brown in female; marking on female segment II convex. Male genitalia as in Figs 32-37. Sensory lobe of left paramere slightly swollen near base; right paramere simple; endosoma with spiculate sclerite at base, lacking lobal sclerite.

Measurements

(♂/♀). Total body length: 3.70 –4.45/4.19– 4.62; width head across eyes: 0.74 –0.80/0.75– 0.85; width vertex: 0.28 –0.30/0.33– 0.37; length of labium; 0.92 –0.97/0.98– 1.10; length of antennal segments I–IV: 0.33 –0.38/0.44– 0.50, 1.40 –1.58/1.44– 1.65, 0.38 –0.43/0.44– 0.60, 0.33 –0.41/0.33– 0.36; length of pronotum including collar: 1.00 –1.08/1.0– 1.26; width base of pronotum: 1.45 –1.60/1.66– 1.81; maximum width across hemelytra: 1.80 –20.4/2.04– 2.21; length of hind femur, tibia, and tarsus: 1.28 –1.45/1.52– 1.68, 1.69 –2.01/1.61– 2.18, 0.27 –0.30/0.29– 0.36.

Distribution.

Japan (Shikoku: Kochi Pref., Tsushima Island).

Etymology.

Named after Mr. Mikio Takai, who first suggested the presence of this new species.

Biology.

According to Mr. M. Takai (pers. obs.), Stethoconus takaii was associated with a colony of Stephanitis yasumatsui Takeya, 1951 ( Tingidae ) on an evergreen broadleaf tree, Trochodendron aralioides Siebold et Zucc. ( Trochodendraceae ). This tingid species is assumed to be a prey item for the mirid.

Remarks.

The male genital structure of this new species is similar to that of S. japonicus except for the shape of the left paramere. Stethoconus takaii can be distinguished from the latter by the following characters. Antennal segment II dark, if middle pale, at least basal 1/3 infuscate (Figs 12-14); areas between punctures on pronotum weakly swollen, but not calloused (Figs 25-26, 30-31); scutellum weakly elevated and dark without marking (Figs 15-16); pale marking on mesepimeron absent (Figs 17-18); basal part of left paramere somewhat swollen. Some specimens of the new species have been misidentified as S. japonicus ( Yasunaga et al. 1997, Nakatani and Yasunaga 2001). The description and illustration by Nawa (1910), on which the specific name S. japonicus was based ( Schumacher 1917; see also Yasunaga et al. 1996), unequivocally correspond to what has been identified as S. japonicus (with only an apically infuscate antennal segment II and a yellow marking on scutellum).