Tremex longicollis Konow 1896
Creators: name: Shinohara, Akihiko
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Siricidae
Tremex
Tremex longicollis

description: Tremex longicollis Konow, 1896
(Figs 2A, D, 3C, 4E, 5C, J, 6A, 7E, F, 9B, 10C, 11B, 12E, 14; Tables 1–4)
Tremex longicollis Konow, 1896: 45; Yano, 1917: 120 (“ longicolis”); Yano, 1932: 473; Gussakovskij, 1935: 67; Esaki et al., 1939: 330; Takeuchi, 1938: 193; Benson, 1943: 30; Maa, 1949: 159; Takeuchi, 1949: 47; Miyatake, 1950: 38; Takeuchi, 1950: 1333; Takeuchi, 1955a: 2, 7; Takeuchi, 1955b: 115; Okutani 1959: 554; Kondo, 1961: 4; Okutani 1962: 343; Takeuchi, 1962: 3, 10; Kim, 1963: 295; Okutani 1963: 25; Okutani, 1967: 44; Kim, 1971: 85; Okutani, 1971: 18; Tanaka, 1971: 202; Kondo & Miyake, 1974: 15; Kondo & Miyake, 1976: 3; Okutani, 1977: 286; Smith, 1978: 99; Tanaka, 1979: 459; Shimoyama, 1986: 7; Abe & Togashi, 1989: 558; Xiao et al., 1992: 56; Tabata & Abe, 1995: 447; Sakamoto, 1997: 25; Lee et al., 1998: 299; Nagase, 2004: 1254; Naito et al., 2004: 68; Yoshida, 2006: 105; Nagase, 2007: 291; Yamazaki & Matsumoto, 2009: 313; Taeger et al., 2010: 108; Funamoto, 2010: 10; Tanaka, 2015: 38; Nagase & Watanabe, 2018: 950; Higurashi, 2019: 93; Lee et al., 2019: 14; Naito, 2019: 20; Naito, 2020: 467; Ogata, 2021: 186.
Tremex similis Marlatt, 1898: 49; Konow, 1899: 86 (synonym of T. apicalis); Matsumura, 1906: 80; Matsumura, 1930: 59; Matsumura, 1931: 79; Matsumura, 1932b: 952; Smith, 1978: 99.
Tremex fuscicornis: Togashi, 1965: 244, plate 122, fig. 15. Not Fabricius, 1787.
See Smith (1978) and Lee et al. (2019) for more synonyms and references.
Diagnostic characters. Female. Length without ovipositor 22–35 mm. Head pale brown, usually with blackish mark across ocellar area. Antenna blackish brown, with two to four basal and one apical antennomeres pale brown (Fig. 5C). Thorax black, at least dorsal half of pronotum (usually without blackish line medially) and sometimes propleuron, parascutal lobe and mesoscutellum marked with pale brown. Legs brown, most of coxae, trochanters, anterior and dorsal surfaces of mid femur, hind femur, dorsal parts of hind tibia and hind tarsomere 1 blackish brown to black (Fig. 6A). Forewing pale brownish hyaline, without distinct infuscation (Fig. 7E, F). Abdomen black, with following pale brown: Most of tergum 2, anterior and often posterior margins of terga 3–6 (tergum 3 often almost entirely), tergum 8 (except anterolateral corner and large roughly heart-shaped black mark at middle), posterior half of tergum 9 (without black area along posterior margin), including entire precornal basin, and cornus. Antenna with 14–16 antennomeres. Pronotum (Fig. 3C) long, MPL 0.74–0.95 (average 0.85) times as long as OOCL. Hind tibia 1.00–1.12 (average 1.07) times as long as hind tarsomere 1; dorsal margin of hind tibia straight or very shallowly concave (Fig. 6A). Forewing 1.10–1.38 (average 1.2) times as long as ovipositor sheath. Abdominal tergum 8 0.94–1.29 (average 1.10) times as long as terga 5–7 combined; precornal basin long, its length 0.74–0.98 (average 0.86) times as long as wide; ovipositor sheath 2.24–2.74 (average 2.55) times as long as apical sheath.
Male. Length 21 mm. Head, antenna, thorax and legs black except as follows: postocular area and temple (gena) entirely pale brown. Antenna with scape and pedicel pale brown (Fig. 5J). Lateral sunken area of parascutal lobe pale brown. Fore leg with posterior half of coxa, femur, tibia and tarsus pale brown; mid leg with part of femur, ventral surface of tibia and apical tarsomere pale brown; hind leg with most of femur and apical tarsomere pale brown. Wings yellowish hyaline, with brownish veins (Fig. 9B). Abdomen pale brown, with entire tergum 1 and narrow anterior lateral margins of each segment blackish. Antenna with 14 antennomeres. Pronotum (Fig. 4E) long, MPL about 0.91 times as long as OOCL. Hind tibia short, 1.19 times as long as hind tarsomere 1.
Material examined. 69♀ 1³ (1♀ from Taiwan, 34♀ from Honshu, 11♀ 1³ from Shikoku, 21♀ from Kyushu and 2♀ with no locality data). See Appendix for collection data.
Distribution (Fig. 14). Japan (Honshu, Shikoku, Kyushu, Tsushima Island),? Korea (see discussion below), Taiwan, China (Fujian (Xiao et al. 1992)).
Host plant. Cannabaceae: Celtis sinensis Pers. (Takeuchi 1949; Okutani 1967).
Remarks. This species occurs in autumn (Table 4) and the female is well characterized by the largely blackish brown antenna (Fig. 5C), the long pronotum (Fig. 2A), the dorsally blackish and ventrally brownish hind tibia (Fig. 6A), the pale brownish wings without distinct infuscation (Fig. 7E, F) and the elongate precornal basin (Fig. 2D). The male of this species is very rare. It was described by Yano (1932), Esaki et al. (1939), Takeuchi (1962) and Naito (2020) but only one specimen listed above was available for the present study. It differs from the males of other Japanese congeners by the pale brown temple, gena, antennal scape and pedicel (Figs 4E, 5J), the pale brown wings without dark cloud (Fig. 9B) and mostly pale brown abdomen (Fig. 12E).
Gussakovskij (1935) noted “ Korea (?)” for the distribution of this species and, probably after him, Kim (1963) also included it in the Korean fauna without giving any collection data. Lee et al. (1998) gave the collection records of three males collected in April and two males collected in August but no females. The identity of these Korean specimens, particularly those collected in April, needs confirmation, because the Japanese specimens examined are all females except for one male as noted above and all were collected in September to October with a few exceptional collection data in July, August and November (Table 4).
The specimens listed in Appendix (also Fig. 14) from Fukushima, Ibaraki, Tochigi, Saitama, Aichi, Mie, Kyoto, Kagawa, Fukuoka, Nagasaki (Tsushima Island) and Kagoshima prefectures represent the first collection records from these prefectures.
Matsumura’s (1906, 1932b) host records of conifers and Okutani’s (1959) host record of “Muku” (= Aphananthe aspera (Thunb.) Planch. (Cannabaceae)) are probably erroneous. Ogata (2021) observed the oviposition of this woodwasp on Podocarpus macrophyllus (Thunb.) Sweet f. angustifolius (Blume) Pilg. (Podocarpaceae). This is an interesting observation, because all the known host plants of Tremex species are angiosperms and T. longicollis is thought to be monophagous on Celtis sinensis (Sakamoto 1997). The host association of T. longicollis with P. macrophyllus f. angustifolius is unlikely and needs confirmation.
description: Published as part of Shinohara, Akihiko, 2023, The woodwasp genus Tremex (Hymenoptera, Siricidae) of Japan, pp. 1-40 in Zootaxa 5239 (1) on pages 22-23, DOI: 10.11646/zootaxa.5239.1.1, http://zenodo.org/record/7621749