Philonix fulvicollis Fitch, 1859(1858), sexual generation

Synonyms: Philonix fulvicollis Fitch (1859: 783), asexual females; Cynips (Teras) fulvicollis combination by Osten Sacken (1865: 379); Biorhiza fulvicollis combination by Ashmead (1885: 296); Biorrhiza fulvicollis combination and incorrect spelling by Dalla Torre (1893: 61); Philonyx fulvicollis combination and incorrect spelling by Smith (1910: 598); Cynips (Philonix) fulvicollis var. fulvicollis form fulvicollis combination by Kinsey (1930: 262); Cynips (Philonix) fulvicollis combination by Kinsey (1936: 207).
Philonix nigricollis Fitch, 1859. Synonymized by Kinsey (1930: 262).
Acraspis niger Gillette, 1889. Acraspis nigra corrected spelling by Dalla Torre (1893: 64); Philonix nigra combination by Beutenmueller (1909: 251); Philonyx nigra combination and incorrect spelling by Smith (1910: 598); Philonix niger correction by Felt (1918: 96). Synonymized by Kinsey (1930: 262).
Acraspis gillettei Bassett, 1900. Acraspis gillettii incorrect spelling by Beutenmueller (1904: 25); Philonix gillettei combination by Felt (1906: 711); Philonyx gillettei combination and incorrect spelling by Smith (1910: 598). Synonymized by Beutenmueller (1909: 252).
Kinsey (1930, 1936) described 6 additional species from the asexual generation and included them within his “fulvicollis complex”: Cynips (Philonix) canadensis Kinsey, 1930 on Q. alba, Q. macrocarpa, Q. michauxii, and Q. muehlenbergii; Cynips (Philonix) major Kinsey, 1930 on Q. alba, Q. macrocarpa, Q. michauxii, and Q. muehlenbergii; Cynips (Philonix) rubricosa Kinsey, 1930 on Q. alba and Q. stellata, Cynips (Philonix) vorisi Kinsey, 1930 on Q. bicolor, Q. michauxii, and Q. macrocarpa; Cynips (Philonix) insulensis Kinsey, 1936 on Q. gambelii and Q. macrocarpa; and Cynips (Philonix) latigenae Kinsey, 1936 on Q. gambelii. Kinsey also included in this complex the taxa Philonix gigas Weld, 1922 on Q. lyrata and Philonix lanaeglobuli (Ashmead, 1887) on Q. michauxii, both known only from an asexual generation, plus Philonix pallipes (Bassett, 1900), known only from a sexual generation on Q. alba. Since then, Melika & Abrahamson (2002) synonymized Philonix pallipes to Acraspis gemula (Bassett, 1881). Weld (1951) and Burks (1979) treated Philonix insulensis (Kinsey), Philonix latigenae (Kinsey), Philonix gigas Weld, and Philonix lanaeglobuli (Ashmead) as distinct valid species, while the rest were treated as varieties of P. fulvicollis. We follow this treatment, thus Philonix fulvicollis var. canadensis (Kinsey), syn. nov., Philonix fulvicollis var. major (Kinsey), syn.nov., Philonix fulvicollis var. rubricosa (Kinsey), syn. nov. and Philonix fulvicollis var. vorisi (Kinsey), syn. nov. are all considered synonyms of P. fulvicollis

Gall. The sexual generation galls (Fig. 204) occur singly in terminal buds of twigs of Q. macrocarpa. The gall is a relatively robust, seed-like, sub-ovoid cell approximately 2 mm long, dark brown when mature with longitudinal striations. Occupies the entire bud when mature, causing stunting or suppression of shoots and leaves produced from the bud.

Biology. See Fitch (1859), Weld (1922a, 1926), and Kinsey (1930, 1936) for the biology of the asexual generation. Asexual generation galls (Fig. 203) in Kinsey’s (1936) “fulvicollis” complex have been recorded on leaves of Q. alba, Q. bicolor, Q. chapmanii, Q. gambelii, Q. lyrata, Q. macrocarpa, Q. michauxii, Q. muehlenbergii, and Q. stellata, (Kinsey 1930, 1936; Burks 1979). Asexual generation females only begin to emerge from galls in the autumn of the year following the year of gall formation (Kinsey 1930), and we recorded females emerging up to four years after the year of gall formation. Adult females of the asexual generation (from galls collected in Manitoba but reared in Edmonton) emerged during the second half of October and early November. Sexual generation galls matured in May in Edmonton, and adults emerged 1–3 June 2008. Galls of the asexual generation appeared on leaves in Edmonton in July.

Distribution. USA: New York, Michigan, Tennessee, Illinois, Kansas (Burks 1979); Canada: Manitoba, Ontario, Quebec, New Brunswick.

Comments. Digweed (2010) treated Philonix gigas (Weld), Philonix insulensis (Kinsey), and Philonix nigra (Gillette) as synonyms of P. fulvicollis, although without formal synonymization. Molecular analysis, however, shows that P. fulvicollis and P. nigra are distinct species.

- James Nicholls, George Melika, Scott Digweed, Graham Stone: (2022) Pairing of sexual and asexual generations of Nearctic oak gallwasps, with new synonyms and new species names (Hymenoptera: Cynipidae, Cynipini)^©