Buffingtonella politus ( Ashmead, 1896 ) Lobato-Vila & Pujade-Villar, 2019

Lobato-Vila, Irene & Pujade-Villar, Juli, 2019, Revision of world Ceroptresini (Hymenoptera: Cynipidae) with the description of a new genus and five new species, Zootaxa 4685 (1), pp. 1-67 : 11-13

Buffingtonella politus ( Ashmead, 1896) comb. nov.

( Figure 2 )

Ceroptres politus Ashmead, 1896 . Trans. Am. Ent. Soc. 23: 187. Type material: USNM.

Type material (examined). LECTOTYPE (♀) with the following labels: ‘ Ceroptres politus Ashm’ (white label with a black frame, handwritten) / ‘Type No. 3285 U.S. N.M.’ (red label) / ‘Va May 20 · 84, ovopositing in midrib of leaf of Q. rubra’ (white label, handwritten) / ‘Through C. V. Riley’ (white label) / ‘ Lectotype ♀ Ceroptres politus Ashmead, 1896 , IL-V desig-2017’ (red label) / ‘ Buffingtonella politus (Ashmead) IL-V det. 2019’ (white label). PARALECTOTYPES (1♂ & 2♀) with the following labels: ‘Through C. V. Riley’ (white label) / ‘3374, from ribgall on leaf of Q. rubra, In Apr. 27 · 85’ (white label, handwritten) / ‘Type No. 3285 U.S. N.M.’ (red label) / ‘USN- MENT 00892998’ (white label, QR code) / ‘ Paralectotype ♂ Ceroptres politus Ashmead, 1896 , IL-V desig-2017’ (red label) / ‘ Buffingtonella politus (Ashmead) IL-V det. 2019’ (1♂); ‘3374, In Apr. 29 · 85’ (white label, handwrit- ten) / ‘Through C. V. Riley’ (white label) / ‘Type No. 3285 U.S. N.M.’ (red label) / ‘USNMENT 00892509’ (white label, QR code) / ‘ Paralectotype ♀ Ceroptres politus Ashmead, 1896 , IL-V desig-2017’ (red label) / ‘ Buffingtonella politus (Ashmead) IL-V det. 2019’ (white label) (1♀); same data as the previous one, but Apr. 30 · 85 and QR code 00892776 (1♀).

Diagnosis. The morphological traits that diagnose B. politus are the same as those outlined in the diagnosis section of Buffingtonella .

Redescription. Female. Length. Body length 1.6–1.8 mm (n=3).

Color ( Fig. 2a ). Brown to chestnut. Head and mesosoma dark brown; tegulae yellow. Antennae and legs, yellow to testaceous; middle and posterior coxae, infuscated; femorae, dusky. Metasoma brown to chestnut, darker posteriorly. Wings hyaline, veins pale yellow.

Head. In anterior view ( Fig. 2e, f ) round-shaped, about 1.1 times as wide as high, genae not expanded behind compound eyes. Face faintly pubescent, lower face with a few weak striae radiating from sides of clypeus and reaching compound eyes, one of them reaching the external margin of the toruli; medially without striae; with neither vertical carinae nor a depressed area between or below the toruli. Clypeus distinct, slightly projected over mandibles. Malar space almost 0.5 times as long as height of compound eye. Anterior tentorial pits visible; pleurostomal sulcus absent, epistomal sulcus slightly impressed. Transfacial line about as long as height of compound eye. Toruli situated slightly below mid-height of compound eye; distance between torulus and compound eye shorter than diameter of the toruli; distance between the toruli clearly shorter than diameter of the toruli. Front finely coriaceous, apparently smooth, with scarce small piliferous punctures; frontal carinae absent. Head in dorsal view ( Fig. 2g ) is about 1.9 times as wide as long. Vertex finely coriaceous, apparently smooth, without punctures. POL:OOL:LOL = 14:7:6 and diameter of lateral ocelli, 5.5. Occiput ( Fig. 2c, d ) finely coriaceous to alutaceous, appearing smooth, without punctures.

Antennae ( Fig. 2i ). 12-segmented; subclavate, just slightly broadened apically; pubescence dense and short. Scape plus pedicel slightly longer than F1; pedicel about as long as wide; F1 about 0.8 times as long as F2, F2 and F3 subequal, the following segments progressively shorter. Last flagellar segment 3.2 times as long as wide and 1.3 times as long as F8+9.

Mesosoma. About 1.4 times as long as high in lateral view ( Fig. 2a ), including nucha, with moderately long, but not densely pubescence. Ratio of length of pronotum medially/laterally: 0.4. Dorsal part of pronotal plate complete, with two distinct and widely separated foveae. Lateral pronotum dorsally coriaceous, basally imbricated; without lateral carina. Mesoscutum ( Fig. 2c ) 1.1 times as wide as long, finely coriaceous, apparently smooth; anterior grooves narrow and weakly impressed, extending 1/3 of the mesoscutal length. Notauli incomplete, extending half of the mesoscutal length, very wide posteriorly and smooth. Parapsidal grooves narrow and weakly impressed, surpassing tegulae. Median groove short and shallow, only visible in the posterior 1/4 of the mesoscutum. Mesoscutellum ( Fig. 2c ) 1.3 times as long as wide, laterally and posteriorly wrinkled, medially finely coriaceous; circumscutellar carina absent; scutellar foveae long and extending to the sides of the mesoscutellum, well defined, weakly sculptured and separated by a very wide septum. Mesopleuron ( Fig. 2a ) smooth and shiny; little pubescent basally. Metapleural sulcus ( Fig. 2a ) reaching 4/5 of the mesopleural height. Propodeum ( Fig. 2j ) faintly pubescent and weakly sculptured, almost smooth; propodeal carinae straight in the anterior 1/3, the posterior 2/3 clearly divergent and terminally somewhat branched. Nucha sulcate dorsally and laterally.

Legs. Tarsal claws bidentate, with a small basal lobe.

Wings ( Fig. 2l ). Forewings pubescent with moderately long marginal setae, longer than total body length. Radial cell closed, almost 2.8 times as long as wide; areolet not well defined, posterior vein pale. Rs+M inconspicuous. Basal cell with sparsely spaced setae.

Metasoma ( Fig. 2k ). Slightly shorter than head plus mesosoma, and 1.3 times longer than high in lateral view. First metasomal tergum ring-shaped and weakly longitudinally sulcate ( Fig. 2c , inset image). Second metasomal tergum short and free, about 0.4 times as long as metasomal length and with sparse pilosity anterolaterally, not forming a patch. Third metasomal tergum without micropunctures; not dorsodistally incised. The following terga, punctate. Prominent part of the hypopygial spine 2.7 times longer than wide and projected.

Male ( Fig. 2b, d, h ). Similar to female, except for the following morphological traits: body length 1.3 (n=1); antennae with 15 segments, filiform, F1 neither excavated nor expanded apically or basally, scape somewhat dusky; scutellar foveae smaller than in females, more or less ovate.

Distribution. USA. State of Virginia ( Ashmead 1896).

Biology. This species was obtained from unknown galls ( Ashmead 1896: 187). According to Ashmead’s description, this species was described from specimens found ovipositing in the midrib of leaves of Quercus rubra L. (Lobatae section) ( Fig. 2n ). The specimen label on one of the types states: ‘from rib-gall on leaf of Q. rubra ’.

Remarks. Ceroptres politus was originally described from 1♂ and 7♀ ( Ashmead 1896: 187). We located and examined 1♂ and 3♀ deposited in USNM. According to Ashmead’s description, C. politus is mainly polished black, with the middle and posterior coxae, and all femorae, dusky or black; however, all the specimens studied have a brownish body (probably due to the passing of time as has been observed in other old specimens).

According to Ashmead (1896), Buffingtonella politus comb. nov. was found ovipositing in the midrib of leaves of Q. rubra , although a label of one specimen from the type series deposited in the entomological collections of USNM adds ‘from a rib-gall’ to the description of its biology. We found a pinned leaf fragment with some nerve swellings that was present together with the types and with the same numerical code as them ( Fig. 2m ), which we suppose are the galls on which Ashmead says B. politus was ovipositing. Based on these data, we are of the opinion that B. politus is an inquiline despite some of its morphological traits, which suggest that it could be a Cynipini (see above). Currently, only two tribes include inquilines of oak galls ( Ronquist et al. 2015): Ceroptresini and Synergini .

Figures

FIGURE 2. Type material of Ceroptres politus Ashmead, 1896: a) female habitus; b) male habitus; c) female dorsal view; d) male dorsal view; e) female lower face; f) female front; g) female head and mesosoma in dorsal view; h) male antenna; i) female antenna; j) propodeum; k) female lateral metasoma; l) forewing; m) pinned leaf fragment of Q. rubra with some nerve swellings deposited in USNM; n) type labels.