Saphonecrus Dalla-Torre and Kieffer, 1910

Lobato-Vila, Irene, Wang, Yiping, Melika, George, Guo, Rui, Ju, Xiaoxue & Pujade-Villar, Juli, 2021, A Taxonomic Review of the Gall Wasp Genus Saphonecrus Dalla-Torre and Kieffer and other Oak Cynipid Inquilines (Hymenoptera: Cynipidae) from Mainland China, with Updated Keys to Eastern Palaearctic and Oriental Species, Zoological Studies (Zool. Stud.) 60 (10), pp. 1-25 : 7-20

Genus Saphonecrus Dalla-Torre and Kieffer, 1910

New material of Saphonecrus deposited in ZAFU’s collection was examined. A total of 13 species of Saphonecrus (out of 27 described from the Eastern Palaearctic and the Oriental region) are known from mainland China, of which four are new records for this region ( S. gilvus Melika and Schwéger, 2015 ; S. globosus Schwéger and Tang, 2015 ; S. leleyi Melika and Schwéger, 2015 ; and S. nantoui Tang, Schwéger and Melika, 2015 ) and two are new species ( S. albidus Lobato-Vila and Pujade-Villar , sp. nov. and S. segmentatus Lobato-Vila and Pujade-Villar , sp. nov.). Additionally, a few more morphotypes have been identified among the samples, each of which probably represent undescribed species; however, given the paucity of material, we have refrained from describing these taxa until more fresh material is obtained. An updated key to Eastern Palaearctic and Oriental species based on the key given by Schwéger et al. (2015b) is provided.

Key to Eastern Palaearctic and Oriental Saphonecrus species a,b

1. Frons with numerous parallel striae, extending from toruli to lateral ocelli. Mesoscutum with strong and prominent transversal carinae. Female antenna 14-segmented .................... S.? serratus

- Frons without parallel striae; smooth, alutaceous, microreticulate, micropunctate or coriaceous; lateral frontal carina usually absent. Mesoscutum from alutaceous or coriaceous to weakly transversely carinate. Female antenna usually 13-segmented, rarely 14 ...................................................................................... 2

2. Lateral frontal carina present, strong, reaching lateral ocellus ..... ..................................................................................... S. yukawai c

- Lateral frontal carina absent ....................................................... 3

3. Lateral pronotal carina absent, anterolateral sides of pronotum rounded in dorsal view. Tarsal claws with basal lobe. Female antenna 13- or 14-segmented ..................................................... 4

- Lateral pronotal carina present, complete or partially complete, anterolateral sides of pronotum usually sharply angled in dorsal view. Tarsal claws usually simple, without a basal lobe, rarely bidentate. Female antenna 13-segmented ................................... 8

4. F1 at most 1.2x as long as F2. POL about 2.5x as long as OOL. Malar space 0.5x as long as height of eye. Syntergite posteriorly without punctures. Female antenna 13-segmented .................... 5

- F1 1.6–2.0x as long as F2. POL 2.0 or less times as long as OOL. Malar space 0.6–0.65x as long as height of eye. Syntergite with small posterodorsal patch of micropunctures. Female antenna 13- or 14-segmented ......................................................................... 6

5. Frons and vertex alutaceous to coriaceous, with scattered punctures. Mesoscutum with weak interrupted transversal carinae. Mesoscutellum wrinkled, scutellar foveae separated by a wide septum. Head 1.8x as wide as long in dorsal view. OOL 2.1x as long as diameter of lateral ocellus. Notauli incomplete, reaching at most to half of mesoscutum length. Radial cell 2.8x as long as wide ................................................................. S. leleyi

- Frons and vertex reticulate. Mesoscutum and mesoscutellum reticulate to delicately coriaceous, scutellar foveae separated by narrow median carina. Head 2.1x as wide as long in dorsal view. OOL 1.3x as long as diameter of lateral ocellus. Notauli complete, sometimes less impressed anteriorly. Radial cell 2.3– 2.5x as long as wide .............................................. S. symbioticus

6. Female antenna 13-segmented. Pedicel almost 2.0x as long as wide. Head 1.5x as wide as high in frontal view and 2.3x as wide as long in dorsal view. Gena slightly broadened behind eye. Face dark brown to black .................................................. S. flavitibilis

- Female antenna 14-segmented. Pedicel 1.3–1.5x as long as wide. Head at most 1.3x as wide as high in frontal view and at most 2.0x as wide as long in dorsal view. Gena not broadened behind eye. Face reddish brown to yellow .................................................... 7

7. Frons and vertex delicately coriaceous, without punctures. POL 1.7x as long as OOL, OOL 1.8–2.0x as long as diameter of lateral ocellus. Mesoscutum with weak interrupted transverse carinae. Scutellar foveae indistinctly defined, with same sculpture as the rest of disk. Face reddish brown, except two blackish brown lateral spots on lower face .................................. S. chaodongzhui

- Frons and vertex delicately coriaceous, with scattered punctures. POL 1.4x as long as OOL, OOL 2.3x as long as diameter of lateral ocellus. Mesoscutum coriaceous to weakly imbricate, without transverse carinae. Scutellar foveae well defined, subtriangular, weakly sculptured. Face mainly yellow ................. .................................................................. S. segmentatus sp. nov.

8. Mesoscutum densely punctuate ................................... S. diversus

- Mesoscutum reticulate, alutaceous, coriaceous or with weak transverse carinae, never densely punctuate .............................. 9

9. Tarsal claws bidentate, with a basal lobe ................................. 10

- Tarsal claws simple, without a basal lobe ................................ 13

10. Malar space 0.5x as long as height of eye. POL 2.0x as long as OOL. Pedicel 1.5x as long as wide. F1 1.6–1.7x as long as F2. Notauli incomplete, short. Female syntergite not incised dorsodistally ...................................................... S. shirokashicola

- Malar space 0.6–0.7x as long as height of eye. POL 2.5–3.0x as long as OOL. Pedicel about 2.0x as long as wide. F1 1.1–1.4x as long as OOL. Notauli complete. Female syntergite slightly incised dorsodistally ................................................................. 11

11. Transfacial distance slightly longer than height of eye. Frons alutaceous, shining. POL 3.0x as long as OOL. Mesoscutum and mesoscutellum delicately coriaceous to alutaceous, mesoscutellum with wrinkles laterally and posteriorly. Radial cell 3.2–3.5x as long as wide ........................................ S. shirakashii

- Transfacial distance as long as height of eye. Frons delicately coriaceous. POL 2.5x as long as OOL. Mesoscutum with weak interrupted transverse carinae or coriaceous with weak transverse elements not forming true carinae, mesoscutellum wrinkled. Radial cell 3.0x as long as wide ............................................... 12

12. Malar space 0.6x as long as height of eye. Vertex delicately coriaceous with very weak, delicate dense transverse striae. OOL slightly longer than diameter of lateral ocelli. Female metasoma slightly longer than high in lateral view ................. S. naiquanlini

- Malar space 0.7x as long as height of eye. Vertex alutaceous to smooth. OOL 1.6x as long as diameter of lateral ocelli. Female metasoma nearly as long as high ............................ S. shanzhukui

13. Notauli incomplete, reaching at most half of mesoscutum length ................................................................................................... 14

- Notauli complete, deep or shallow, somewhat interrupted by the sculpture of mesoscutum, but always reaching the pronotal margin ....................................................................................... 16

14. Female and male more than 2.0 mm in length. Head rounded in frontal view. In both sexes, pedicel globose, about as long as wide, and F1 nearly equal to F2. Mesoscutellum alutaceous to coriaceous, weakly wrinkled posteriorly and laterally. Radial cell 4.0x as long as wide .................................................. S. longinuxi

- Female 1.4–1.8 mm long, male 1.0– 1.6 mm long. Head trapezoid in frontal view. Pedicel more than 1.5x as long as wide at least in females (nearly as long as wide in males of S. salicinai ), and F1 1.5 or more times as long as F 2 in both sexes. Mesoscutellum wrinkled. Radial cell 3.2–3.5x as long as wide ........................ 15

15. Transfacial distance as long as height of eye. POL 2.3x as long as OOL and OOL 1.7x as long as diameter of lateral ocelli. Pedicel 1.5–1.6x as long as wide in both sexes. Syntergite without punctures posterodorsally ........................................... S. globosus

- Transfacial distance slightly shorter than height of eye. POL 3.0x as long as OOL and OOL slightly longer than diameter of lateral ocellus. Pedicel 2.1x as long as wide in females, slightly longer than wide in males. Syntergite with a small patch of micropunctures posterodorsally ................................ S. saliciniai

16. Radial cell of the fore wing at most 3.0x as long as wide ........ 17

- Radial cell of the fore wing at least 3.5x as long as wide ........ 23

17. Lateral pronotal carina short and incomplete or weak, indistinct dorsally, pronotum slightly or not sharply angled in dorsal view. ................................................................................................... 18

- Lateral pronotal carina strong and complete, reaching lateral edge of pronotum, pronotum sharply angled in dorsal view ............ 19

18. Malar space 0.6x as long as height of eye. Transfacial distance slightly shorter than height of eye. Frons and vertex coriaceous. POL 1.7x as long as OOL and OOL slightly longer than diameter of lateral ocellus. F1 1.2–1.3x as long as wide in both sexes. Median mesoscutal impression shallow but visible. Female syntergite incised dorsodistally. Reared from galls on Lithocarpus ............................................................................... S. emarginatus

- Malar space 0.7x as long as height of eye. Transfacial distance 1.2x as long as height of eye. Frons and vertex alutaceous, shining. POL 2.6x as long as OOL and OOL 1.5x as long as diameter of lateral ocellus. F1 1.7x as long as F 2 in females, 2.3 in males. Median mesoscutal impression absent. Female syntergite not incised dorsodistally. Reared from galls on Quercus .......................................................................................... S. gilvus

19. Head and mesosoma dark brown to black; metasoma yellow. Malar space about 0.3x as long as height of eye. Transfacial distance 0.7x as long as height of eye. Mesoscutum and mesoscutellum alutaceous to delicately coriaceous, mesoscutellum with weak wrinkles posteriorly and laterally. Median mesoscutal impression in form of a short incision ........... .......................................................................... S. albidus sp. nov.

- Head and mesosoma reddish brown, dark brown or black; metasoma reddish brown to dark brown. Malar space 0.6 or more times as long as height of eye. Transfacial distance at least 0.9x as long as height of eye, usually equal or longer. Mesoscutum with weak interrupted transverse carinae, mesoscutellum wrinkled. Median mesoscutal impression absent ..................... 20

20. F1 slightly longer than F 2 in both sexes. Scutellar foveae separated by a wide septum. Reared from galls on Lithocarpus ... ................................................................................................... 21

- F1 1.3–1.4x as long as F 2 in females, 1.5–1.6 in males. Scutellar foveae separated by a narrow carina. Reared from galls on Quercus .................................................................................... 22

21. Head subtrapezoid in frontal view, gena slightly broadened behind eye. Vertex delicately coriaceous. Female syntergite incised dorsodistally, with a small patch of micropunctures. In males, lower face, malar space and gena with sparse setae .......... ................................................................................... S. lithocarpi

- Head rounded in frontal view, gena not broadened behind eye. Vertex smooth. Female syntergite not incised dorsodistally, without micropunctures. In males, lower face, malar space and gena with dense whitish setae ............................... S. taiwanensis

22. Malar space 0.7–0.8x as long as height of eye. Scutellar foveae with smooth, shining bottom. Radial cell 2.7–2.8x as long as wide. Female syntergite slightly incised dorsodistally .... S. fabris

- Malar space 0.6x as long as height of eye. Scutellar foveae with some wrinkles on smooth bottom. Radial cell 2.5x as long as wide. Female syntergite strongly incised dorsodistally ................. ....................................................................................... S. nantoui

23. Vertex smooth. Pedicel almost 3.0x as long as wide .. S. nichollsi

- Vertex alutaceous. Pedicel about 2.0x as long as wide ............ 24

24. Head trapezoid in frontal view. Transfacial distance slightly longer than height of eye. Radial cell about 4.0x as long as wide ................................................................................................... 25

- Head rounded in frontal view (except in males of S. taitungi , which is trapezoid). Transfacial distance slightly shorter than height of eye. Radial cell 3.6–3.7x as long as wide ................. 26

25. Malar space 0.6x as long as height of eye. OOL 1.3x as long as diameter of lateral ocellus. Female syntergite slightly incised dorsodistally, with small patch of micropunctures. Males 2.2–2.3 mm in length, with F1 1.2x as long as F2 and weakly incised medially, very slightly expanded apically and basally ..... S. morii

- Malar space 0.8x as long as height of eye. OOL slightly longer than diameter of lateral ocellus. Female syntergite not incised dorsodistally, without micropunctures. Males 1.3–1.6 mm in length, with F1 1.5x as long as F2 and strongly curved and incised medially, strongly expanded apically, not expanded basally ..................................................................... S. pachylomai

26. Gena not broadened behind eye. POL 2.7x as long as OOL. OOL about 1.3x as long as diameter of lateral ocellus. Scutellar foveae indistinctly delimited, with wrinkled bottom. Female syntergite strongly incised dorsodistally. Hypopygial spine longer than wide. Reared from galls on Quercus ........................... S. robustus

- Gena slightly broadened behind eye. POL 2.2x as long as OOL. OOL slightly longer than diameter of lateral ocellus. Scutellar foveae well delimited, weakly sculptured. Female syntergite slightly incised dorsodistally. Hypopygial spine as long as wide. Reared from galls on Lithocarpus ................................ S. taitungi

a Based on the key by Schwéger et al. (2015b) but omitting the Western Palaearctic species, since these are not present neither in the Eastern Palaearctic nor in the Oriental region. Saphonecrus excisus and S. sinicus are considered as nomen dubium and incertae sedis, respectively (see the discussion), and are not included in the key.

b Saphonecrus areolatus (Weld) , from Philippines, is not included in the key because it is no longer a Saphonecrus ( Lobato-Vila et al. 2021) .

c Saphonecrus yukawai Wachi, Ide and Abe was transferred to Synergus by Schwéger et al. (2015b) and re-established in Saphonecrus by Ide et al. (2018).