Two new species of the genus Agramma (Hemiptera, Heteroptera, Tingidae) from small islands of Japan, with an illustrated key to the Japanese species of the genus Author Souma, Jun https://orcid.org/0000-0002-2238-5015 Shirakami Research Center for Environmental Sciences, Faculty of Agriculture and Life Science, Hirosaki University, Aomori, Japan kodokusignal@gmail.com text Deutsche Entomologische Zeitschrift 2024 2024-01-30 71 1 49 65 http://dx.doi.org/10.3897/dez.71.108270 journal article http://dx.doi.org/10.3897/dez.71.108270 1860-1324-1-49 4DB4BB2471794A63A6448C4DE86AFC6F 16F9F77DAD2058BF89E2281A8FAE45A6 Agramma (Agramma) izuense sp. nov. Figs 2B, C , 3B , 4B , 5B-D , 6B , 7B , 8B , 9B , 10C Japanese name: Hachijonaga-gunbai Agramma nexile (non Drake, 1948): Tomokuni and Ishikawa (2002 : 170) (distribution); Yamada and Tomokuni (2012 : 188) (distribution: part); Yamada and Ishikawa (2016 : 429) (distribution: part). Misidentifications. Agramma japonicum (non Drake, 1948): Souma (2020 : 532) (distribution: part). Misidentification. Type series. Holotype (submacropterous ♂, SIHU), "[JAPAN]: Izu Isls., Hachijo Is., Mitsune, Mt. Hachijo-Fuji" [=JAPAN: Izu Islands: Hachijo Island: Southeastern foothills of Mt. Hachijo-Fuji (approximate coordinates: 33°07'34.5"N , 139°47'10.7"E )], 18.v.2021, leg. J. Souma. Paratypes (submacropterous 46 ♂♂ 36 ♀♀), JAPAN: Izu Islands: Hachijo Island: as holotype (submacropterous 8 ♂♂ 4 ♀♀, SIHU); as holotype but 16.v.2021 (submacropterous 3 ♂♂ 6 ♀♀, SIHU); as holotype but 21.v.2021 (submacropterous 6 ♂♂ 10 ♀♀, SIHU); alt. 250-530 m of Mt. Hachijo-Fuji, 4.vii.2001, leg. M. Tomokuni (submacropterous 1 ♂, NSMT); Noboryo Pass, 17.v.2021, leg. J. Souma (submacropterous 9 ♂♂ 3 ♀♀, SIHU; 3 ♂♂ 4 ♀♀, TUA); as above but 5.vii.2001, leg. M. Tomokuni (submacropterous 5 ♂♂ 2 ♀♀, NSMT); Ohkago, 19.v.2021, leg. J. Souma (submacropterous 7 ♂♂ 5 ♀♀, SIHU); Western foothills of Mt. Hachijo-Fuji, 21.v.2021, leg. J. Souma (submacropterous 4 ♂♂ 2 ♀♀, SIHU). Eight specimens collected in 2001 were recorded as " Agramma nexile (Drake, 1948)" by the previous study ( Tomokuni and Ishikawa 2002 ). Additional material examined. Non-types (1 nymph, SIHU), Japan : Izu Islands : Hachijo Island : as holotype but 16.v.2021 . The single nymph recorded above was in poor condition and was thus not described in the present study . Diagnosis. Agramma (Agramma) izuense sp. nov. is recognized among other species of Agramma by a combination of the following characters: pubescence on body less than 0.5 times as long as diameter of compound eye; antennal segment IV brown (Fig. 2B, C ); posterior process in apical part and hemelytron sometimes irregularly dark (Fig. 5C ); thoracic sterna, pygophore and female terminalia black (Figs 4B , 6B , 7B ); head with a pair of frontal spines (Figs 3B , 8B ); rostrum reaching middle part of mesosternum; pronotum without paranotum; median carina of pronotum distinct on posterior process; anterior margin of hemelytron gently curved outward (Fig. 5B, D ); apices of hemelytra separated from each other at rest; R+M (radiomedial) vein of hemelytron present in apical part, carinate throughout its length; costal area usually with 2 rows of areolae at widest part; discoidal-sutural area with 7-8 rows of areolae at widest part; outer and inner margins of paramere angularly curved in middle part (Fig. 9B ); and female terminalia hexagonal in ventral view, with posterior margin protruding posteriad in middle part. Figure 4. Rostra of four Agramma species from Japan, ventral view: A. (Agramma) abruptifrons ( A ); A. (A.) izuense sp. nov. ( B ); A. (A.) japonicum ( C ); A. (A.) keramense sp. nov. ( D ). Scale bars: 0.2 mm. Figure 5. Hemelytra of four Agramma species from Japan, dorsal view: A. (Agramma) abruptifrons ( A ); A. (A.) izuense sp. nov., male ( B, C ) and female ( D ); A. (A.) japonicum ( E ); A. (A.) keramense sp. nov. ( F ). Scale bars: 0.2 mm. Figure 6. Male terminalia of four Agramma species from Japan, ventral view: A. (Agramma) abruptifrons ( A ); A. (A.) izuense sp. nov. ( B ); A. (A.) japonicum ( C ); A. (A.) keramense sp. nov. ( D ). Scale bars: 0.2 mm. Description. Submacropterous male . Head, calli, pronotal disc, basal part of posterior process, thoracic pleura, thoracic sterna, sternal laminae, apical part of tarsi and abdomen black; antenna, frontal spine, buccula, rostrum, collar, apical part of posterior process, hemelytron and legs except apical part of tarsi brown; apical part of posterior process and hemelytron sometimes irregularly dark; compound eyes dark red; pubescence on body yellowish (Figs 2B , 3B , 4B , 5B, C , 6B ). Body (Fig. 2B ) oblong; pubescence on body less than 0.5 times as long as diameter of compound eye. Head (Figs 3B , 8B ) glabrous, with a pair of frontal spines; frontal spines separated from each other at apices, not reaching apex of clypeus; antenniferous tubercles obtuse, slightly curved inward; clypeus smooth; vertex coarsely punctate. Compound eye round in dorsal view. Antenna densely covered with pubescence throughout its length and tiny tubercles in segments I to II; segment I cylindrical; segment II cylindrical, shortest among antennal segments; segment III longest among antennal segments; segment IV cylindrical, longer than segment I. Bucculae contiguous with each other at anterior ends, with 3 rows of areolae throughout their length. Rostrum (Fig. 4B ) reaching middle part of mesosternum. Pronotum (Figs 3B , 8B ) unicarinate, without paranotum. Pronotal disc coarsely punctate. Hood absent. Collar coarsely punctate; anterior margin gently curved inward. Calli smooth. Median carina ridge-like, distinct on posterior process. Posterior process well-developed, flattened, triangular. Thoracic pleura coarsely punctate. Ostiolar peritreme oblong. Mesosternum (Fig. 4B ) as wide as metasternum at widest part. Sternal laminae nearly straight throughout their length. Legs smooth, covered with pubescence. Hemelytron (Fig. 5B, C ), extending beyond apex of abdomen; anterior margin gently curved outward; apices separated from each other at rest; C (costal) and R+M (radiomedial) veins present, carinate throughout their length; Cu (cubital) vein indistinct; costal area usually with 2 rows of areolae at widest part, rarely with a single row throughout its length; subcostal area with 3-4 rows of areolae at widest part; discoidal-sutural area with 7-8 rows of areolae at widest part; hypocostal lamina with a single row of areolae throughout its length. Abdomen oblong in dorsal and ventral views. Pygophore (Fig. 6B ) compressed dorsoventrally, semicircular in ventral view, covered with pubescence. Paramere (Fig. 9B ) slender, expanded in middle part; outer and inner margins angularly curved in middle part, covered with pubescence in middle part. Measurements (n = 20). Body length with hemelytra 2.1-2.4 mm; maximum width across hemelytra 0.8-0.9 mm; length of antennal segments I to IV 0.2 mm, 0.1 mm, 0.5 mm, and 0.3 mm, respectively; pronotal length 0.8-0.9 mm; pronotal width across humeri 0.6 mm; hemelytral length 1.4-1.6 mm; maximum width of hemelytron 0.4-0.5 mm. Submacropterous female . General habitus very similar to that of male (Figs 2C , 5D , 7B ) except for the following characters: subcostal area of hemelytron wider than in male, with 4-5 rows of areolae at widest part; apical part of abdomen hexagonal in ventral view; posterior margin of terminalia protruding posteriad in middle part; and ovipositor with well-developed ovivalvula at base. Figure 7. Female terminalia of four Agramma species from Japan, ventral view: A. (Agramma) abruptifrons ( A ); A. (A.) izuense sp. nov. ( B ); A. (A.) japonicum ( C ); A. (A.) keramense sp. nov. ( D ). Scale bars: 0.2 mm. Measurements (n = 20). Body length with hemelytra 2.4-2.6 mm; maximum width across hemelytra 0.9-1.0 mm; length of antennal segments I to IV 0.2 mm, 0.1 mm, 1.5 mm, and 0.3 mm, respectively; pronotal length 0.9-1.0 mm; pronotal width across humeri 0.6-0.7 mm; hemelytral length 1.6-1.8 mm; maximum width of hemelytron 0.5-0.6 mm. Remarks. In a previous study, Agramma (Agramma) izuense sp. nov. was misidentified as A. (A.) japonicum ( Tomokuni and Ishikawa 2002 ), because both species are the most similar among the Asian species of the genus Agramma . However, the former is easily distinguished from the latter by the following characters: posterior process in apical part and hemelytron sometimes irregularly dark (brown in A. (A.) japonicum ) (Figs 2B, D , 5C, E ); apices of hemelytra separated from each other at rest (close to each other in A. (A.) japonicum ) (Figs 2C , 5B, D ); R+M (radiomedial) vein carinate throughout its length (carinate in basal part and not carinate in apical part in A. (A.) japonicum ); and costal area usually with 2 rows of areolae at widest part (a single row in A. (A.) japonicum ). Morphological differences between the new species and the other two Japanese species are provided in the identification key below. On the other hand, the new species is similar in general appearance to A. (A.) ruficorne (Germar, 1835), which is widely distributed in the Palaearctic Region ( Pericart and Golub 1996 ; Aukema et al. 2013 ). Nevertheless, A. (A.) ruficorne shares the morphological features mentioned in the above paragraph with A. (A.) japonicum so that it is easily distinguished from A. (A.) izuense sp. nov. Distribution. Japan (Izu Islands: Hachijo Island) (Fig. 12 ) ( Tomokuni and Ishikawa 2002 ; Yamada and Tomokuni 2012 ; Yamada and Ishikawa 2016 ; present study). Agramma (Agramma) izuense sp. nov. inhabits the forest floor in the warm-temperate climate of the Izu Islands in the Palaearctic Region. Etymology. The specific epithet refers to its occurrence in the Izu Islands, Japan; an adjective. Host plants. Carex sp. ( Cyperaceae ) (Fig. 11B ) (present study). Although the host plant species could not be identified, Agramma (Agramma) izuense sp. nov. feeds only on this cyperaceous herb and appears to be monophagous. Biology. Agramma (Agramma) izuense sp. nov. feeds on the abaxial surface of the leaves of the abovementioned cyperaceous plant (present study). Dozens of type materials consisting of only submacropterous morphs were collected, suggesting that this new species is flightless. Adults and nymphs were collected in May and July ( Tomokuni and Ishikawa 2002 ; present study).