Pygolampis amamiko, Okuda & Yoshikawa & Ishikawa, 2024

Okuda, Kyosuke, Yoshikawa, Akihiro & Ishikawa, Tadashi, 2024, Pygolampis amamiko (Hemiptera: Heteroptera: Reduviidae), a new assassin bug species from the Amami Islands, Japan, Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 64 (1), pp. 213-221 : 214-219

Pygolampis amamiko sp. nov.

Pygolampis sp. : TANAKA et al. (2013): 15 (listed, survey of Ukejima Island, Japan).

Type locality. Japan: Ryukyus: Amami-Ôshima Is.: Toen, Yamato-son, approximately 28°20′16.8″N 129°20′03.1″E.

Type material. HOLOTYPE: J, JAPAN: RYUKYUS: AMAMI- ÔSHIMA IS.: “ Toen , Yamato-son / 16.vi.2013 / H. Ishii ” ( TUA) . PARATYPES: JAPAN: RYUKYUS: AMAMI- ÔSHIMA IS.: 1J, “Mt.Yuwan-dake / 4.viii.1996 / M. Uchida” ( SMNH); 1J, “Aoku,Sumiyô-son / 25.vi.2003 / S. Hatsushiba” ( TUA); 1♀, “Toen,Yamato-son / 21.vi.2013 / H.Ishii” ( TUA); 1J, “Oganeku,Yamato-son, Ôshima-gun / 19.v.2017 /A.Yoshikawa” ( TUA); 1♀, “Oganeku,Yamato-son, Ôshima-gun / 9.vi.2017 /A.Yoshikawa” ( TUA); 1 J, “Oganeku, Yamato-son, Ôshima-gun / 6.vii.2017 / A. Yoshikawa” ( TUA); 1♀, “Oganeku,Yamato-son,Ôshima-gun / 22.vii.2017 / A.Yoshikawa” ( TUA); 1♀, Oganeku,Yamato-son, Ôshima-gun / 17.ix.2017 / A. Yoshikawa” ( TUA); 1J, Oganeku,Yamato-son, Ôshima-gun / 10.xi.2017 / A. Yoshikawa” ( TUA); 1 ♀, Yui, Setouchi-chô / 29.iv.2018 / A. Yoshikawa” ( TUA); 1 J, Naon, Yamato-son, Ôshima-gun / 12.iv.2021 / A. Yoshikawa” ( TUA); 2 JJ 1 ♀, “Nesebu, Naze, Amami-shi / 10.v.2022 / T. Matsuta” ( TUA); 1 L5 (5th nymph), “Naze-nishinakakatsu,Amami-shi / 23.ix.2022 / by Shifting / T. Matsuta” ( TUA). UKEJIMA IS.: 1 J, “Mt. Ô-yama / 10.ix.2012 / K. Ogaki & Y. Tanaka” ( TUA).

Diagnosis. This new species can be easily distinguished from other species of Pygolampis using a combination of the following features: body length 18.0– 19.2 mm in male and 21.5–22.0 mm in female; general color dark brown to reddish-brown; ocelli not elevated; antennal scape approximately 1.3 times as long as head, with long erect setae ventrolaterally; anteroventral spines of prothorax long, acute, curved upward, and subequal to length of eye in dorsal view; male hind femora exceeding apex of abdomen. Description. Male (holotype). Coloration. General color dark brown to reddish-brown ( Figs 1a–c ), laterally with longitudinal yellowish-brown stripe on thorax. Head dark brown. Compound eyes black; ocelli reddish-brown. First visible labial segment pale brown; second and third visible labial segments dark brown. Antennal scape and pedicel dark brown; first and second flagellomeres dark brown. Pronotum mostly reddish-brown, with pair of yellowish- -brown spots along posterior margin. Fore and middle coxae dark brown in basal 2/3 and yellowish-brown in apical 1/3; hind coxae yellowish-brown, with brownish spots. Trochanters yellowish-brown. Fore and middle femora dark brown, gradually paler base, with irregular yellowish- -brown spots; hind femora reddish-brown, with apical 1/7 blackish. Fore and middle tibiae yellowish-brown, with blackish annulations on base, basal 2/5 and apex; hind tibiae reddish-brown, with blackish annulation on base. Tarsi yellowish-brown. Hemelytra dark brown ( Fig. 3a ). Abdomen dorsally reddish-brown and ventrally pale brown, with black spots along anterior margin of sternites II to VII ( Fig. 1b ); connexiva dark brown; spiracle black.

Vestiture. Body covered with pale fine decumbent setae. Compound eyes sparsely covered with erect setae. First visible labial segment sparsely covered with fine suberect setae dorsally. Antennae covered with fine suberect setae; scape with long erect setae ventrolaterally. Scutellum without setae. Legs covered with suberect setae; fore femora with row of dense short erect setae ventrally. Hemelytra covered with pale fine decumbent setae on coria and glabrous on membranes.

Structure. Body approximately 6.0 times as long as its maximum width. Head ( Fig. 4a ) cylindrical, approximately 2.2 times as long as width across eyes, approximately 0.9 times as long as pronotum, furnished with setigerous tubercles on apex of clypeus (tylus) and along posterior and ventrolateral margins; anteocular area approximately 1.7 times as long as postocular area, nearly parallel-sided in dorsal view; clypeal process moderately long, well exceeding apex of head (labrum), bilobate at apex. Ocelli not elevated. First visible labial segment ( Fig. 4b ) curved at base, extending to postocular area; proportional lengths of segments I to III: 6.3: 1.5: 1.0. Antennal scape approximately 1.3 times as long as head; proportional lengths of segments I to IV: 5.7: 7.0: 1.0: 1.7.

Pronotum trapezoidal, 2 times as long as its maximum width; humeri round; posterior angle weakly convex; posterior margin weakly concave in middle; anterior pronotal lobe with three pairs of shallow glabrous areas. Anteroventral spines of prothorax thick, acute, curved upward, and subequal to length of eye in dorsal view ( Fig. 1a ). Scutellum triangular, approximately 1.3 times as long as its basal width, swollen upward. Fore femora slightly robust, approximately 10 times as long as its maximum width; hind femora slightly exceeding apex of abdomen. Hemielytra rather short, reaching middle of abdominal tergite III.

Abdomen fusiform, widest at segment V, approximately 3.3 times as long as its maximum width. Posterolateral projections of tergite VII ( Figs 3b , 4c ) triangular, as long as its width, apically round; posterior margin of tergite VII wholly concave roundly.

Genitalia. Pygophore ( Figs 4e–f ) oval in ventral and lateral views, approximately 1.5 times as long as its maximum width, with short sparse setae ventrally; median process ( Fig. 4g ) long, bent inward, slightly widened at apex in posterior view. Parameres ( Fig. 4h ) widened in apical half, apically round, approximately 3 times as long as its maximum width, ventrally and dorsally covered with erect setae, and with large tooth on apical 1/5 dorsally. Phallus ( Figs 4i–j ) elongate when not extended; basal plate approximately 0.6 times as long as phallus when not extended; struts parallelly running to each other, apically curved inwards, close to each other at apex, with apices acute. Endosoma ( Fig. 4k ) membranous, simple in structure.

Female. General aspects as in male ( Figs 2a–c ), except for the following characters: body approximately 7 times as long as its maximum width; hind femora extending to abdominal segment VII; median extension of abdominal sternite VII reaching middle of sternite VI ( Fig. 4d ); abdominal segment IX ( Fig. 3c ) strongly projected, gradually narrowed posteriad; styloids tongue-shaped, incised at apex, submarginally covered with short setae arranged in row ( Fig. 4l ); apical incision of styloids 0.15 times as long as styloids.

Measurements. See Table 1.

Comparative note. The general appearance of this new species is very similar to Pygolampis breviptera Ren, 1981 found in China and Vietnam ( REN 1981, OKUDA & CHEN 2021), and P. aptena Swanson, 2018 from Belize (SWAN- SON & CHORDAS 2018). However, it can be distinguished from P. breviptera by the antennal scape with long erect setae ventrolaterally (which are absent in P. breviptera ), the hemelytra extending to the middle of abdominal tergite III (reaching the posterior portion of tergite IV or V in P. breviptera ), and the abdomen with black spots along the anterior margin of sternites II to VII (without black spots in P. breviptera ). It can also be distinguished from P. aptena by the posterolateral projections of abdominal tergite VII apically round (in P. aptena , acute), the hemelytra not extending to the posterior portion of abdominal tergite III (reaching a posterior portion of tergite III in P. aptena ), and the abdomen fusiform to oval, ventrally pale brown, with black spots along the anterior margin of sternites II to VII (abdomen oval, weakly expanded; uniformly dark brown in P. aptena ). The differences from the other Japanese species are given in the identification key below.

Etymology. The present species is named after the Ryukyuan mythical goddess Amamiko who created the Amami Islands, the type locality of the new species; a noun in apposition.

Biology. Pygolampis amamiko sp. nov. was found only on the relatively humid forest floor with fallen trees and underbrush at night ( Figs 5a–e ), suggesting it is nocturnal.

Distribution. Japan: Amami Islands (Amami-Ôshima Island, Ukejima Island) ( Fig. 6 ).

Figures

Fig. 1. Pygolampis amamiko sp. nov., male habitus: a – dorsal view; b – ventral view; c – lateral view. Scale bars = 5 mm.

Fig. 3. Pygolampis amamiko sp. nov., details: a – male hemelytra; b–c – apical parts of abdomen, dorsal view (b – male, c – female). Scale bars = 2 mm.

Fig. 4. Diagnostic characteristics of Pygolampis amamiko sp. nov. (setae omitted in a–d). a–b – male head (a – dorsal view, b –lateral view); c–d – apical parts of abdomen, ventral view (c – male, d – female); e–f – pygophore (e – lateral view, left paramere omitted; f – dorsal view); g – median process of pygophore, posterior view; h – left paramere, diverse views; i–j – phallus, not everted (i – lateral view, j – ventral view); k – endosoma, everted condition, lateral view; l – styloides, dorsal view. Scale bars = 1 mm for a–d; 0.5 mm for e, f, h–l; 0.25 mm for g. Abbreviations: avsp – anteroventral spines of prothorax; bp – basal plates; cp – clypeal process; dps – dorsal phallothecal sclerite; eds – endosoma; mp – median process; pd – pedicel; str – struts of phallus.

Fig. 2. Pygolampis amamiko sp. nov., female habitus: a – dorsal view; b – ventral view; c – lateral view. Scale bars = 5 mm.

Fig. 5. Pygolampis amamiko sp. nov., living individuals on a fallen tree. a – adult male; b – adult female; c – 5th instar nymph; d–e – habitats (c: photographed by Takahiro Komatsu).

Fig. 6. Distribution map of Pygolampis amamiko sp. nov.