Belonocnema quercusvirens, Burks, 1979

Zhang, Y. Miles, Egan, Scott P., Driscoe, Amanda L. & Ott, James R., 2021, One hundred and sixty years of taxonomic confusion resolved: Belonocnema (Hymenoptera: Cynipidae: Cynipini) gall wasps associated with live oaks in the USA, Zoological Journal of the Linnean Society 193 (4), pp. 1234-1255 : 1244-1248

Belonocnema quercusvirens, Burks, 1979 .

Material examined: Asexual generation – Syntype 1F ‘ USA: FL, Clearwater , Reared Dec-13–19, Quercus geminata, L.H.Weld Collector, Hopk. U.S. 15634f, Type 24099, USNMENT 00802094’; Paratype 9F same locality as Syntype USNMENT 00893032, 00893095, 00893115, 00893123, 00893218; 4F ‘ USA:SC, Charleston Co. S. Car ’43, Q. virginiana, 1160a , USNM’; 2F ‘ USA: FL, Archbold Biol. Stn., 27.1846, -81.3521, 19/X/2016, Ott Lab, Q. geminata ’; 5F ‘ USA: FL, Dickinson State Pk., 27.0261, -80.1090, 18/X/2016, Ott Lab, Q. geminata ’; 5F ‘ USA: FL, Oceanside Village , 29.9542, -85.4277, 30/X/2016, Ott Lab, Q. geminata ’.

Sexual Generation – 7F3M ‘ USA: FL, Archbold Biol. Stn. , 27.1846, -81.3521, IV/2018, Egan Lab, Q. geminata ’; 5F5M ‘ USA: FL, Dickinson State Pk. , 27.0261, -80.1090, III/2017, Egan Lab, Q. geminata ’; 5F5M ‘ USA: FL, Lake Lizzie , 28.2277, -81.1800, III/2018, Egan Lab, Q. geminata ’; 4M ‘ USA: FL, Volusia Co. Daytona Beach, IV-6-1998, Urban beachside UV light trap, C Yorke, S. Fullerton, UCFC 0017693 , 0017694 , 0017695 , 0017696 ’; 1F2M ‘ USA: FL, Brevard Co. Malabar, Malabar Rd. 30 Mar – 25 May 2000, P.J. Russell, Z. Prusak, S.M. Fullerton, UCFC 0079161 , 0100100 , 0101364 ’; 2F3M ‘ USA: FL, Brevard Co. Titusville, SR 405, 21 Feb–15 May 2001, Z. Prusak, P.J. Russell, S.M. Fullerton, UCFC 0078923 , 0079318 , 0093022 , 0093669 , 0103143 ’; 2F2M ‘ USA: FL, Orange Co. Rk. Spr. Rn. St. Res. IV-13–1995, S.M. Fullerton, UCFC 0201995 , 0202004 , 0202411 , 0202415 ’; 5F5M ‘ USA: FL, Orange Co. UCF 28°36’37”N 81°12’01”W LLP Flatwds, M. Carey, S.L. Kelly , S.M. Fullerton, III-28–2008, UCFC 0463902 , 0463926 , 0463936 , 0463954 , 0463957 , 0464351 , 0464355 , 0464384 , 0464390 , 0464524 . 8F4M ‘ USA: FL, Orange / Osceola Co. Walt Disney World, 24 Mar–28 Apr 1998, Z. Prusak, S. Fullerton, UCFC 0017132 , 0017146 , 0017173 , 0017230 , 0017232 , 0017601 , 0017602 , 0017603 , 0017604 , 0017608 , 0017787 , 0017793 ’; 2M ‘ USA: FL, Sarasota Co. MCC- Venice Campus , III-31- 1997, K.J. Maharay, S.M. Fullerton, UCFC 0018361 , 0018363 ’; 2F1M ‘ USA: FL, Seminole Co. Econ. Wild. Area IV-8-2000, T . Smith , UCFC 0054591 , 0054607 , 0060190 ’; 2F1M ‘ USA: FL, Seminole Co. Lower Wekiva River St. Preserve, 28-IV-2001, P.J. Russell, S.M. Fullerton, UCFC 0108938 , 0109646 , 0109778 ’; 3F ‘ USA: FL, Seminole Co. Oveido, rural yard, Malaise trap, IV-7-1994, S.M. Fullerton, UCFC 0202173 , 0202175 , 0202190 ’; 4F6M ‘ USA: FL, Seminole Co. Oveido, rural yard, UV light, 28°39’25”N 81°10’44”W, S.M. Fullerton, III-28–IV-12-2009, UCFC 0446980 , 0446991 , 0446992 , 0446993 , 0446994 , 0446996 , 0448649 , 0448658 , 0448659 , 0448660 ’.

Diagnosis: Belonocnema fossoria can be distinguished from the other two known species by the spur on the anterior side of fore tibia longer than basitarsus and tibial spurs ( Fig. 3A ). The asexual generation has small, non-functional wings, lack of areolet in the front wing, and the middle tibia with an additional spur.

Description

Asexual female ( Figs 1D , 3A–C ): Body length 2.5– 3.5 mm (N = 12). Reddish brown; tip of mandibles, wing veins dark brown ( Fig. 3A ). Head finely coriaceous with sparse white setae; slightly rounded in dorsal view; 2.3× as broad as long in dorsal view; 1.2× as broad as long in frontal view; slightly broader than mesosoma. Gena alutaceous, not broadened behind eye in dorsal view; 1.2× as broad as cross diameter of eye. Malar space alutaceous, without striae radiating from clypeus; eye 2.1× higher than length of malar space. Inner margins of eyes parallel. OOL 1.6× longer than POL; OOL 2.3× longer than LOL; ocelli ovate, all equal in size. Transfacial distance 1.8× longer than height of eye and 1.5× longer than height of lower face ( Fig. 3C ); diameter of antennal torulus 2.3× longer than distance between them, distance between torulus and eye margin 1.4× longer than diameter of torulus. Lower face finely coriaceous, with white setae, without striae radiating from clypeus, median area not elevated. Clypeus trapezoid, flat, broader than high, with deep anterior tentorial pits, distinct epistomal sulcus and clypeopleurostomal line. Frons finely coriaceous, glabrous; vertex, interocellar area, occiput is finely coriaceous. Postgena coriaceous, glabrous. Antenna 13 segmented, longer than head + mesosoma; F1 shorter than the length of scape + pedicel, 1.7× longer than F2 ( Fig. 3C ).

Mesosoma longer than high in lateral view. Propleuron alutaceous, with few setae. Mesoscutum smooth, glabrous between notauli, alutaceous lateral to notaulus; longer than broad (width measured across base of tegulae); notauli complete, deeply impressed for full length; median mesoscutal line distinct; anterior parallel lines and parapsidal lines absent ( Fig. 3B ); Mesoscutellum only slightly longer than broad, slightly broader posteriorly; shorter than mesoscutum, uniformly rugose, overhanging metanotum; scutellar foveae present but shallow and indistinct. Mesopleural triangle large, sparsely setose; Mesopleuron smooth, glabrous, with a few white setae along ventral and anterior margins. Lateral propodeal carinae distinct, central propodeal area glabrous, with rugae; lateral propodeal area alutaceous, with dense white setae; nucha short, coriaceous. Legs short and stout; tibia setose on anterior edge; fore tibia prolonged on the anterior side into a curved spine ( Fig. 3A ), longer than basitarsus and the tibial spur; tarsal claws simple with a slight ridge but never a full tooth. Middle tibia also with curved spine but smaller than basitarsus and tibial spurs; middle and hind tibia with two spurs. Tarsi covered in setae. Fore wing hyaline, shorter than body and often curved upwards, margin with dense cilia; Radial cell 2× as long as wide; 2r and Rs infumated, Rs curved upwards and thickened at apex; radial cell open; areolet absent; Rs + medial vein (M) reaching to M; cubitus-anal crossvein (cu-a) absent; first cubitus vein (cu1) broken ( Fig. 3B ). Metasoma slightly longer than head + mesosoma, as long as high in lateral view, smooth and glabrous; second metasomal tergite occupies setose medially; all subsequent tergites without setae, smooth, glossy; ventral spine of the hypopygium short, prominent part as long as broad in ventral view, with white setae extending beyond the apex of spine ( Fig. 3A ).

N = number tested; * see Supporting Information, Table S1 for corresponding site abbreviations.

Sexual female ( Figs 1B , 3E ): Body length 3.5–4.5 mm (N = 16). Reddish brown; pedicel, flagellomeres, vertex, tip of mandibles, tarsal claws, wing veins dark brown ( Fig. 3E ). Head finely coriaceous with sparse white setae; slightly rounded in dorsal view; 1.8× as broad as long in dorsal view; 1.3× as broad as long in frontal view; slightly broader than mesosoma. Gena alutaceous, not broadened behind eye in dorsal view; 0.7× as broad as cross diameter of eye. Malar space alutaceous, without striae radiating from clypeus; eye 2.1× higher than length of malar space. Inner margins of eyes parallel. OOL 1.6× longer than POL; OOL 1.4× longer than LOL; ocelli ovate, all equal in size. Transfacial distance 1.6× longer than height of eye and 1.3× longer than height of lower face; diameter of antennal torulus 2× longer than distance between them, distance between torulus and eye margin 1.3× longer than diameter of torulus. Lower face finely coriaceous, with white setae, without striae radiating from clypeus, median area not elevated. Clypeus trapezoid, flat, broader than high, with deep anterior tentorial pits, distinct epistomal sulcus and clypeo-pleurostomal line. Frons finely coriaceous, glabrous; vertex, interocellar area, occiput is finely coriaceous. Postgena coriaceous, glabrous. Antenna 14 segmented, longer than head + mesosoma; F1 shorter than the length of scape + pedicel, 1.3× longer than F2 ( Fig. 3E ). Mesosoma longer than high in lateral view. Propleuron alutaceous, with few setae. Mesoscutum smooth, glabrous between notauli, alutaceous lateral to notaulus; longer than broad (width measured across base of tegulae); notauli complete, deeply impressed for full length; median mesoscutal line distinct; anterior parallel lines and parapsidal lines absent; mesoscutellum only slightly longer than broad, slightly broader posteriorly; shorter than mesoscutum, uniformly rugose, overhanging metanotum; scutellar foveae present. Mesopleuron smooth, glabrous, with a few white setae along ventral and anterior margins; mesopleural triangle setose. Lateral propodeal carinae bent outwards, central propodeal area glabrous, with rugae; lateral propodeal area alutaceous, with dense white setae; nucha short, coriaceous. Legs short and stout; tibia setose on anterior edge; fore tibia prolonged on the anterior side into a curved spine, longer than basitarsus and the tibial spur; tarsal claws simple with a slight ridge but never a full tooth. Middle tibia also with curved spine but smaller than basitarsus and tibial spurs; middle and hind tibia with two spurs. Tarsi covered in setae ( Fig. 3E ). Fore wing hyaline, shorter than body and often curved upwards, margin with dense cilia; radial cell 2× as long as wide; 2r and Rs infumated, Rs curved upwards and thickened at apex; radial cell open; areolet present; Rs + M reaching to M; cu-a absent; cu1 broken ( Fig. 3E ). Metasoma slightly longer than head + mesosoma, as long as high in lateral view, smooth and glabrous; second metasomal tergite occupies setose medially; all subsequent tergites without setae, smooth, glossy; ventral spine of the hypopygium short, prominent part 1.5× as long as broad in ventral view, with white setae extending beyond the apex of spine ( Fig. 3E ).

Male: Body length 3.2–4.1 mm (N = 15). Colour and sculptures like the sexual female, Antenna 15 segmented; F1 is curved, excavated, and incised medially. Metasoma smaller than head + mesosoma.

Gall: Smooth, single-chambered pea galls (5.88– 6.45mm in diameter) on the ventral side of leaves for the asexual generation ( Fig. 1C ); irregular shaped, multilocular galls often in clusters on the small rootlets for the sexual generation ( Fig. 1A ; Egan et al., 2013). Host plant: Quercus geminata .

Distribution: Georgia, Florida ( USA).

Biology: The small, often bent wings of the asexual generation ( Figs 1D , 3A ) appear to be non-functional ( Table 2 ), and the large tibial spur and short, stout legs are likely fossorial adaptations that allows B. fossoria to reach the rootlets of Q. geminata in sandy soil where these species co-occur. The sexual generation emerges from early March to mid-April, corresponding with the timing of leaf flush of their host Q. geminata ( Hood et al., 2019) .

Remarks: Osten Sacken’s (1861) original description of C. quercusvirens was based on the asexual galls alone collected on ‘live oak’ in Georgia, the wasp itself was described by Weld (1921) as B. fossoria . As both B. treatae and B. fossoria can be found in the region and both induce similar galls, it is difficult to know which species Osten Sacken collected and named. However, names described before 1930, and which were applied only to the product of an animal, are valid names for the organism itself under ICZN Article 1, section 3. Therefore, we here propose the name B. quercusvirens as species inquirenda.

Figures

Figure 1. Belonocnema fossoria (A–D), Belonocnema kinseyi (E, F). A, sexual-generation root gall. B, adult female sexual generation. C, fully lignified asexual-generation leaf gall on Q. geminata. D, adult asexual generation. E, fully lignified asexual-generation leaf gall on Q. fusiformis. (Leaf galls produced by B. kinseyi on Q. fusiformis and Q. virginiana are indistinguishable from leaf galls produced by B. treatae on Q. virginiana.) F, adult asexual generation (by Jena Johnson).

Figure 3. Belonocnema fossoria. A, lateral habitus of asexual-generation female syntype, arrow pointing to tibial spur. B, dorsal habitus of asexual-generation female syntype. C, frontal view of asexual-generation female syntype. D, label of syntype specimen. E, lateral habitus of sexual-generation female. (Photos A–D by Rachel Osborn, USNM: http://n2t.net/ ark:/65665/36d24dd5f-fe3b-4085-aecd-0568264b43a9, Accessed 28 September 2020)