Nesodiprion and its species groups

Nesodiprion Rohwer, 1910

Diagnosis. Postocellar area with distinct anterior and lateral furrows (lateral furrow sometimes very short in male) (Figs 5–6). Supraclypeal area weakly or moderately swollen. Female flagellum biramose or biserrate (middle flagellomeres each with pair of ventral projections) (Figs 7A–J). Male flagellum biramose except for first flagellomere and apical one or two flagellomeres. Anterior edge of mesoscutellum acute or obtuse (Figs 9A–L). Distance between cenchri 0.2–1.0 × width of cenchrus (Figs 10A–F). Metascutellum 0.3–0.5 × as long as width of cenchrus, 0.3–0.7 × as long as distance between lateral ocelli. Hind leg (Figs 12A–M) with posterior tibial spur simple, 0.7 × or more as long as first tarsomere in female, 0.9 × or more in male. Claws with inner tooth. In hind wing, section of vein 1A between crossveins a and cu-a 0.6–1.5 × as long as width of cell 1A (usually less than 1.3 ×). Middle abdominal terga shiny, and smooth or slightly microsculptured dorsally. In female, lance with short apical cleft and small posterior projection of processus articularis (Figs 15A–O). In male genitalia, ergot small (Figs 18A–F).

Nesodiprion tsugae group: Nesodiprion kojimai and N. tsugae .

Diagnosis. Anterior end of lateral ocellus located anterior to level of posterior end of median ocellus (Figs 5A– E). Malar space wide, 1.0–1.6 × width of median ocellus. In female antenna (Figs 7A–B), first flagellomere with ramus length 0.4–1.1 × first flagellomere length along dorsal margin. Prepectus broad, with length (= short axis) about 1/4 or more of postspiracular sclerite length (Figs 8A–B), often narrow and its length less than 1/4 of postspiracular sclerite length in male of N. kojimai (Fig. 8C). Mesoscutellar appendage in dorsal view linear, visible along apical margin of mesoscutellum throughout (Fig. 10A). In hind leg (Figs 12A–D), posterior tibial spur 0.7–1.0 × length of first tarsomere exclusive of pulvillar pad in female, 0.9–1.2 × in male, and 1.0–1.4 × breadth of tibia in lateral view in female, 1.5–1.9 × in male; second and third tarsomeres combined 1.2–1.6 × as long as first in female, 1.0–1.2 × in male. In female, hypopygium with posterior margin narrowly and slightly concave medially, posteromedially without pair of heavily sclerotized projections as in Fig. 14A (condition of N. tsugae unknown). Ovipositor sheath (Figs 14D–G) in posterodorsal view about 2.5–3.0 × as wide as cercus (condition of N. tsugae unknown), with apical margin rounded laterally; scopa membranous, large and oval. Lance in lateral view (Figs 15B, D) slightly broadening basally, with several narrow membranous areas. Lancet (Figs 16A–C) with ventral margin not distinctly convex in outline; basal and middle serrulae almost equal in size and shape, and each posteriorly angulated. Valviceps nearly flat (Figs 17A–D). Host plants: Abies and Tsuga .

Nesodiprion niger group: Nesodiprion niger (male unknown).

Diagnosis. As in N. tsugae group, but female flagellum biserrate (Figs 7C–D) and prepectus very small as in Fig. 8D. Host plant: Unknown.

Nesodiprion flavipes group: Nesodiprion flavipes .

Diagnosis. As in N. tsugae group, but prepectus narrow in both sexes (Fig. 8E), often very small in female (Fig. 8D), lance in lateral view distinctly broadening basally, with several wide membranous areas (Fig. 15H) and lancet with basal and middle serrulae simple (Figs 16E–F). Host plant: Tsuga .

Nesodiprion japonicus group: Nesodiprion albiventris (male unknown), N. biremis (Konow, 1899), N. japonicus, N. kagaensis, N. orientalis Hara & Smith, 2012, N. nigerrimus (male unknown) and “ N. sp. (? huanglongshanicus)” in Hara & Smith (2012).

Diagnosis. Anterior end of lateral ocellus located anterior to level of posterior end of median ocellus (Figs 6A– F). Malar space 0.1–0.8 × width of median ocellus. In female antenna (Figs 7F–H), first flagellomere with ramus length 1.6–4.1 × first flagellomere length. Prepectus narrow (Figs 8F–G) or very small (Fig. 8H). Mesoscutellar appendage in dorsal view linear, visible along apical margin of mesoscutellum throughout (Figs 10D–E). In hind leg (Figs 12H–K), posterior tibial spur 1.0–1.4 × length of first tarsomere, 1.3–2.2 × breadth of tibia in both sexes; second and third tarsomeres combined 0.8–1.1 × as long as first in both sexes. In female, hypopygium with posterior margin narrowly and slightly concave medially, posteromedially without pair of heavily sclerotized projections (Fig. 14B) (conditions of N. albiventris and N. nigerrimus unknown). Ovipositor sheath (Figs 14L–T) about 1.0–2.0 × as wide as cercus, with apical margin acutely convex laterally; scopa membranous, vertically narrow. Lance in lateral view (Figs 15I, K) distinctly broadening basally, with membranous area on each annuli connected with each other (condition of N. albiventris unknown). Lancet (Figs 16G–J) with ventral margin convex at second annulus in outline; basal and middle serrulae heteromorphic; serrula of second annulus largest (condition of N. albiventris unknown). Valviceps in dorsal view laterally convex on apical part (Figs 17G–J). Host plants: Pinus and Larix .

Nesodiprion shinoharai group: Nesodiprion shinoharai .

Diagnosis. Anterior end of lateral ocellus located slightly behind level of posterior end of median ocellus (Figs 6G–I). Malar space 1.0–1.6 × width of median ocellus. In female antenna (Figs 7I –J), first flagellomere with ramus indistinct or its length 0.2–0.6 × first flagellomere length. Prepectus very small (Figs 8I –J). Mesoscutellar appendage in dorsal view not visible except for narrow apex (Fig. 10F). In hind leg (Figs 12L–M), posterior tibial spur 1.1–1.4 × length of first tarsomere, 1.5–1.9 × breadth of tibia in both sexes; second and third tarsomeres combined 0.9–1.2 × as long as first in both sexes. In female, hypopygium with posterior margin widely concave medially, posteromedially with pair of heavily sclerotized projections (Fig. 14C). Ovipositor sheath (Figs 14U–Y) about 3.5 × as wide as cercus; scopa not membranous. Lance in lateral view (Figs 15M, O) distinctly broadening basally, with membranous area on each annuli connected with each other. Lancet (Figs 16K–L) with ventral margin strongly convex at second and third annuli; serrulae of second and third annuli enlarged and fused, forming one large four-dentate serrula. Valviceps nearly flat (Figs 17K–L). Host plant: Pinus .

Remarks. The distribution of character states in Diprionidae is summarized in Table 1. We show only the characters concerned with Nesodiprion, and regard the states of these characters in Monoctenus as plesiomorphic (shown as 0 in Table 1) except the state is variable in Monoctenus, because Monoctenus is considered the sister group of the Diprioninae (see Malm & Nyman 2015).

We have not found any apomorphic character states showing the monophyly of Nesodiprion . The biserrate or biramose female flagellum (character 3 state 1) suggests the relationship of Nesodiprion and Gilpinia tohi . However, the distribution of the character 3 state 1 is not harmonious with the distributions of the other apomorphic character states. On the other hand, the very large posterior projection of a processus articularis (character 14 state 3) suggests the relationship of G. tohi and Diprion . This view matches with the distributions of the other apomorphic states besides the character 3 state 1 and those variable in G. tohi or Diprion (characters 5, 9, 12 and 15). We, therefore, consider G. t o h i not related to Nesodiprion but to Diprion .

Nesodiprion shinoharai is a peculiar diprionid having the ocelli as in many tenthredinids (character 1 state 1; e.g., Viitasaari, 2002b). It is presumably due to the reduction of ocelli (compare Figs 6G–I with Figs 6A–F). The hypopygium posteromedially with a pair of projections (character 11 state 1) suggests the relationship of this species to G. tohi and Diprion . This view matches with the distributions of the concealed mesoscutellar appendage (character 7 state 2) and the lancet with heteromorphic basal and middle serrulae (character 16 state 1), but not with the distributions of the distinctly microsculptured abdominal terga (character 10 state 1) and the large posterior projection of a processus articularis (character 14 states 2+3). Investigation of more characters will be needed to clarify the relationship of N. shinoharai and other diprionine species.

The monophyly of the N. japonicus group is supported by the female first flagellomere with a very long ramus (character 4 state 1). The distributions of the lance with fused membranous areas (character 15 state 1) and the lancet with heteromorphic basal and middle serrulae (character 16 state 1) may suggest that the N. japonicus group (1) Based on unpublished observations; species examined, Monoctenus cryptomeriae, M. itoi, M. juniperi and M. nipponicus; see also Smith (1975). (2) Present study. (3) Based on Hara & Smith (2012) and present study. (4) Based on unpublished observations. (5) Based on Hara (2014) and unpublished observations; species examined, Microdiprion hakusanus and M. pallipes . (6) Based on unpublished observations. (7) Based on Hara & Nakamura (2015) and Hara & Shinohara (2015). (8) Based on unpublished observations; species examined, Gilpinia daisetusana, G. hercyniae and G. polytoma . (9) Based on unpublished observations. (10) Based on unpublished observations; species examined, Diprion hani, D. nipponicus and D. pini .

is more closely related to N. shinoharai and/or some of the other diprionine genera than to the N. tsugae group, N. niger and N. flavipes . The distribution of the basally distinctly broadening lance (character 13 state 1) suggests that N. flavipes is more closely related to the N. japonicus group + N. shinoharai + the other diprionine genera than to the N. tsugae group and N. niger . The monophyly of the N. tsugae group is uncertain, although the members are very similar to each other.