Pamphilius komonensis Takeuchi 1930

Pamphilius komonensis Takeuchi, 1930 Japanese name: Kaede-hirata-habachi (Fig. 3; Table 1) Material examined. HONSHU: Tochigi Pref.: 7 ♀1 ♂ listed in Table 1. Ibaraki Pref.: 3♀ listed in Table 1. SHIKOKU: Tokushima Pref.: Ochiai-toge, Miyoshi, 8. VI. 2021, A. Watanabe. For more records, see Shinohara and Zhou (2006) and Anonymous (2023). Larva. Early instar (Fig. 3C): Head black; trunk creamy white. Late instar (Fig. 3D, G): Head and antenna pale olive. Trunk greenish white; dorsal prothoracic field dark olive; lateral prothoracic shield and cervical sclerite black; thoracic legs and subanal appendage creamy white; lateral basin of suranal plate, suranal hook and subanal plate blackish. Mature larva (Fig. 3H): Head pale olive or pale brownish green with antennae dark brown. Trunk including all appendages vivid pale green; dorsal prothoracic field concolorous to head or blackish; lateral prothoracic shield and cervical sclerite black; lateral basin of suranal plate, suranal hook and subanal plate dark olive to black; central basin of suranal plate often blackish. Distribution. Japan (Honshu, Shikoku, Kyushu). New record from Ibaraki Prefecture and Tokushima Prefecture. Host plant. Sapindaceae: Acer pictum Thunb. (Shinohara and Okutani, 1983), A. amoenum Carrière var. amoenum (new record), A. palmatum Thunb. (new record), A. pictum Thunb. subsp. dissectum (Wesm.) H.Ohashi f. connivens (G.Nicholson) H.Ohashi (new record). Life history. The collection records of over 1000 specimens (Shinohara and Zhou, 2006; Anonymous, 2023) show that the adults are active in the field mainly in May, the earliest record being April 21, 2007, in the lowland of Hiratsuka City, Kanagawa Prefecture and the latest record being July 10–13, 1995, in Hachimantai (ca. 1000–1300 m alt.), Iwate Prefecture. In Nakagawa, Tochigi Prefecture, the larvae of this species were found in late May to early July, they matured in mid-June to late July, and the adults emerged in mid-April to early May of the following year (Table 1). This species is regarded as univoltine as other pamphiliine sawflies. The larva is a solitary leaf-roller (Fig. 3). The leaf-roll is made always on the underside of the leaf. It is a specialized, tight, screw-like tube, with the apex closed (Fig. 3E, F; type b of Viitasaari, 2002b). The late instar larva occasionally moves onto another leaf carrying the screw-like abode. Remarks. Shinohara and Okutani (1983) first recorded the host plant of this species, but the immature stages and biology have not been studied before. As shown above, P. komonensis may be associated with various species of maples. This pamphiliid is widely distributed in Honshu, Shikoku and Kyushu (Shinohara and Zhou, 2006; Anonymous, 2023). Here we record this species from Ibaraki Prefecture and Tokushima Prefecture for the first time.小松平锤角叶蜂（Pamphilius komonensis Takeuchi, 1930），日文名：枫平场蜂（Kaede-hirata-habachi）（图3；表1）。 检视标本。本州：栃木县：7头雌虫、1头雄虫，详见表1；茨城县：3头雌虫，详见表1。四国：德岛县三好市落合峠，2021年6月8日，渡边明采。更多采集记录参见Shinohara与Zhou（2006）及Anonymous（2023）。 幼虫。低龄幼虫（图3C）：头部黑色，躯干奶白色。高龄幼虫（图3D、G）：头部与触角淡橄榄色；躯干绿白色；前胸背板域暗橄榄色；前胸侧盾片与颈骨片黑色；胸足及亚肛附器呈奶白色；肛上板侧凹、肛钩与亚肛板黑褐色。成熟幼虫（图3H）：头部淡橄榄色或淡棕绿色，触角暗褐色；躯干连同所有附器呈鲜亮淡绿色；前胸背板域与头部同色或黑褐色；前胸侧盾片与颈骨片黑色；肛上板侧凹、肛钩与亚肛板呈暗橄榄色至黑色；肛上板中央凹常呈黑褐色。 分布。日本（本州、四国、九州），茨城县与德岛县为该种的新分布记录。 寄主植物。无患子科：元宝枫（Acer pictum Thunb.，Shinohara与Okutani, 1983）、紫花枫（A. amoenum Carrière var. amoenum，新记录）、鸡爪槭（A. palmatum Thunb.，新记录）、细裂元宝枫（A. pictum Thunb. subsp. dissectum (Wesm.) H.Ohashi f. connivens (G.Nicholson) H.Ohashi，新记录）。 生活史。据逾1000号标本的采集记录（Shinohara与Zhou, 2006；Anonymous, 2023），成虫野外活动盛期为5月，最早记录为2007年4月21日（神奈川县平冢市低地），最晚记录为1995年7月10—13日（岩手县八幡平，海拔约1000—1300 m）。在栃木县中川地区，该种幼虫于5月末至7月初被发现，6月中旬至7月下旬成熟，次年4月中旬至5月上旬成虫羽化（表1）。与其他锤角叶蜂亚科物种一致，该种为一化性昆虫。 幼虫营独居卷叶生活（图3），其卷叶始终形成于叶背，为特化的紧实螺旋管状结构，顶端封闭（图3E、F；Viitasaari, 2002b中的b型）。高龄幼虫偶尔会携带其螺旋状虫巢转移至其他叶片。 备注。Shinohara与Okutani（1983）首次记录了该种的寄主植物，但此前尚未对其未成熟虫态与生物学特性开展研究。如前文所述，小松平锤角叶蜂可能与多种槭树属物种相关联。该锤角叶蜂科物种广泛分布于本州、四国与九州（Shinohara与Zhou, 2006；Anonymous, 2023）。本文首次报道该种在茨城县与德岛县的分布记录。