Feron stellulum ( Burnett, 1974 ) Cuesta-Porta & Melika & Nicholls & Stone & Pujade-Villar, 2023

Cuesta-Porta, Victor, Melika, George, Nicholls, James A., Stone, Graham N. & Pujade-Villar, Juli, 2023, Re-establishment of the Nearctic oak cynipid gall wasp genus Feron Kinsey, 1937 (Hymenoptera: Cynipidae: Cynipini), including the description of six new species, Zootaxa 5366 (1), pp. 1-174 : 124-127

Feron stellulum ( Burnett, 1974) comb. nov.

Figs 367–371

Andricus stellulus Burnett, 1974: 299 , female, gall.

Type examined. HOLOTYPE: Asexual female “Cajon Pass, San Bernardino Co., CA. 12.1974. Host: Quercus dumosa ; emerged II-19-1974. J.A. Burnett Coll. ”, “ Andricus stellulus det. by J. Burnett ”, red label “ Holotype ”, red label “Type No. 15448 USNM ”, handwriting label “ Andricus stellulus Burnett ” deposited in USNM, not examined. Specimen data and images available at http://n 2t.net/ark:/65665/3f622315a-cbf9-4fb2-9eb6-c3694b2219c0.

Diagnosis. Asexual females belong to the group of Feron species characterised by a body which is not black; the head is rounded or trapezoid to triangular in frontal view, ocelli are not elevated above the frons; inner margins of eyes parallel or very slightly converging ventrally, the transfacial distance is equal to or longer than the height of eye; toruli are located above the mid-height of eyes; the eye is less than 3.0× as high as length of the malar space; lateral ocelli smaller, OOL at least 2.5× as long as the diameter of the ocellus, if shorter then the head and mesosoma are not yellowish or light brown; the pronotum laterally with longitudinal carinae; the mesoscutum alutaceous to coriaceous, rugose-reticulate, reticulate, without piliferous points and the mesopleuron in the mid-height with transverse reliculate-carinate band; as in F. gigas (asex), F. parmula (asex), F. syndicorum (asex) and some specimens of F. tibiale (asex). Differs from F. tibiale and F. syndicorum in having the gena which is not broadened behind the eye in frontal view. Differs from F. parmula in that the malar space has a few delicate striae radiating from the clypeus, mesoscutellar foveae defined and the prominent part of the ventral spine of the hypopygium 4.5× as long as broad in ventral view; see more characters at couplet 37 in the key. The most morphologically similar species is F. gigas but F. stellulum has the antenna with 11 flagellomeres (12 in F. gigas ), the eye 2.7× as high as the length of malar space (shorter in F. gigas ), veins are brown (lighter in F. gigas ), areolet present (absent in F. gigas ) and the central propodeal area with rugae (without rugae in F. gigas ).

Re-description. After Burnett (1974); the images ( Figs 367–370 ) can also be consulted at: http://n 2t.net/ark:/ 65665/3f622315a-cbf9-4fb2-9eb6-c3694b2219c0.

Head and mesosoma rufescent to yellow brown; antenna with black flagellomeres, legs yellowish brown; metasoma brown. Head coriaceous, transverse in dorsal view, as broad as mesosoma. Occiput flat, gena not broadened behind eyes; vertex slightly projected above as a truncate cone, base laterally extended to ocular sutures, several small humps in area of dorsal ocelli. Malar space 0.37× of eye height, with a few striae radiating from clypeus, malar sulcus absent. Interocellar area broader than high. Antenna filiform, with 11 flagellomeres, F1 longer than F2. Mesonotum coriaceous, with scattered setae; notaulus complete, broader posteriorly; median mesoscutal line absent, parapsidal lines marked with smooth stripes. Mesoscutellum with setae, disc reticulate, longer than broad. Mesoscutellar foveae smooth, partly striate, smooth and shining below. Tarsal claws with strong basal lobe. Propodeal carinae bent outwards, central propodeal area darker than rest of propodeum, glabrous, slightly rugose. Fore wing hyaline, pubescent, with dense cilia on margin, veins brown, radial cell open, 4.0× as long as broad, areolet distinct, Rs and R1 not reaching wing margin. Metasoma as high as long, as long as head+mesosoma; 2nd metasomal tergum with setae anterolaterally, micropunctate, subsequent terga with micropunctures, prominent part of ventral spine of hypopygium 4.5× as long as broad in ventral view. Body length 1.5–2.2 mm.

Gall ( Fig. 371 ). Leaf gall. Monolocular and can be found on both sides of the leaves. Disk shaped (1.6-2.3 mm in diameter) with some points around the perimeter but erected on a long and slender pedicel, usually slightly broadening towards apex. The gall is almost twice as high as the diameter of the disk (2.3–5.6 mm in height). The surface is shiny and glabrous of a reddish colour, the pedicel is crimson, and the disk is rufous. Galls are found attached either to a secondary vein of the leaf blade or occasionally to the midrib, mature galls are typically associated with a brown necrosis around the point of attachment which extends laterally to the leaf-blade margin. Emergence holes made by the gall wasp are usually found in the lateral part of the gall disc ( Burnett 1974).

Biology. Only the asexual generation is known, inducing galls on Q. dumosa (section Quercus , subsection Dumosae); adults start to emerge from February.

Distribution. USA: CA.

Figures

FIGURES 367–369. Feron stellulum, comb. nov., asexual female. 367, general habitus, dorsal view, 368, general habitus, lateral view, 369, head and antenna, frontal view (pictures taken from the holotype deposited at the USNM by M. Buffington).

FIGURES 370–371. Feron stellulum, comb. nov., asexual generation. 370, general habitus, lateral view (pictures taken from the holotype deposited at the USNM by M. Buffington). 371, gall (image courtesy J. Gross).