Diognetus yamato Yasunaga, 2023

Yasunaga, Tomohide, Schwartz, Michael D. & Chérot, Frédéric, 2023, Revision of the plant bug genus Diognetus, with descriptions of thirteen new species from the Oriental and Eastern Palearctic Regions (Hemiptera: Heteroptera: Miridae), Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 63 (1), pp. 1-55 : 53-54

Diognetus yamato Yasunaga nom. nov.

( Figs 3G–H, 19E–F, 21H–J, 22J–L, 36A–I)

Yamatolygus pilosus Yasunaga, 1994: 119 (original description) [= junior secondary homonym of Diognetus pilosus ( Poppius, 1914) ].

Yamatolygus pilosus: SCHUH (1995) : 972 (catalog); KERZHNER & JOSI- FOV (1999): 182 (catalog); YASUNAGA (2001): 268 (diagnosis), fig. 318 [wrongly figured as D. flavigenis ]; SCHUH (2002 –2013) (online catalog); AUKEMA (2018) (online catalog); OH et al. (2018): 482 (faunal list).

Type material examined. Yamatolygus pilosus : HOLOTYPE: J, JAPAN: HONSHU: Aomori Pref., Mutsu City, Mt. Osoreyama , 41.30, 141.08, 2 Aug 1953, H. Hasegawa ( NIAES, without USIs, image available on http://www.naro.affrc.go.jp/archive/niaes/inventory/insect/dbhemiptera/y_pilosus.html) . PARATYPES: JAPAN: KYUSHU: Oita Pref., Takeda City, Mts. Kuju, Daisen-rindo (trail), 33.11, 131.26, on flower of Hydrangea paniculata , 1 Aug 1988, Y. Abe, 1 J ( AMNH _ PBI 00380757), 1 ♀ ( TYCN); Kumamoto Pref., Izumi Village [= current Yatsushiro City, Izumi Town], Mt. Shiratori, 32.4800, 131.0044, 27–28 Jun 1987, R. Noda, 1 J ( AMNH _ PBI), 1 ♀ ( TYCN). SHIKOKU: Kochi Pref., Honkagawa Village [= current Ino Town], 33.750, 133.200, T. Befu, 1 J ( AMNH _ PBI) ( TYCN).

Additional material examined. JAPAN: HONSHU: Nagano Pref., Azumino City, Jonen–Mitsumata, 36.30, 137.75, 6 Jul 1988, M. & S. Gotoh, 1 ♀ ( TYCN); Niigata Pref., Tsunan Town, Mt. Yamabushi, 37.0241, 138.5858, UV lighting, 11 Aug 2002, S. Sakurai, 1J ( TYCN); Niigata Pref., Myoko City, Hikosa Waterfall, 36.8863, 138.0566, 1 Aug 1994, K. Sueyoshi, 1 J 1 ♀ ( TYCN); Okayama Pref., Shinjo City, Mt. Kenashi, 35.2344, 133.5144, 14 Jul 1994, T. Nozaki, 1 ♀ ( WCF); Wakayama Pref., Kumano area, Hatenashi Mts., Mt.Ando, 1,100 m alt., 33.8977 135.6200, UV lighting, 7 Jul 1994, S. Gotoh, 1 ♀ ( TYCN). KYUSHU: Fukuoka Pref., Yame City, Mt. Shakadake, 33.20, 130.84, UV lighting, 23 Jun 2019, T. Nozaki, 1 J ( WCF). SHIKOKU: Kochi Pref.,Agawa-gun, Teragawa, Shirasa, 33.7691777 133.183555, flowers of Symplocos coreana (H.Lév.) Ohwi , 2–3 Aug 2002, T. Yasunaga, 3 JJ 3 ♀♀ ( TYCN).

Redescription. For description see YASUNAGA (1994, as Yamatolygus pilosus ). Measurements. See Table 1.

Differential diagnosis. Readily distinguished from other congeners by the following unique characters: moderate to large size (5.0–6.0 mm); castaneous to dark reddish- -brown general coloration ( Figs 3G–H, 19E–F); dark antennal segments I and II (median part of segment II sometimes pale as in Figs 3G–H); long labium exceeding apex of metacoxa ( Fig. 19F); rather inflated scutellum ( Fig. 36A); and pale brown cuneus with fuscous apical 1/3–1/2. The male and female genitalic structures are also unique to D. yamato ( Figs 21H–J, 22J–L, 36F–I): Left paramere with triangular protuberance on sensory lobe ( Fig. 21H); right paramere constricted subapically ( Fig. 21I); heavily sclerotized vesica with developed spiculum ( Fig. 21J); widened interramal lobe and dorsal structure that are entirely covered with comb-like scar microstructures and lacking distinct spines ( Figs 36G–H); and thick-rimmed sclerotized ring ( Fig. 22K).

Etymology. From an ancient name of Japan, Yamato, also referring to the synonymized generic name Yamatolygus Yasunaga ; latinized as a noun in apposition.

Biology. As suggested by YASUNAGA (1994), this species is associated with deciduous Symplocaceae host plants, Symplocos coreana (H.Lév.) Ohwi and S. sawafutagi Nagam from which its immature forms were confirmed. The eggs appear to hibernate, and the adults are found on the host flowers and fruits between late June and early August. Some teneral adults were also collected from inflorescence of Hydrangea paniculata Sieb. & Zucc. ( Hydrangeaceae ).

Distribution. Japan (Honshu, Shikoku, Kyushu), Korea; this species has the northernmost distribution among known congeners and is restricted to montane deciduous broadleaf forests in Shikoku and Kyushu.