Ceroptres pisum ( Osten-Sacken, 1861 ), 1865

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 : 46-47

Ceroptres pisum ( Osten-Sacken, 1861)

( Figures 4f , 8 a–d)

Sarothrus ? pisum Osten-Sacken, 1861 . Proc. Ent. Soc. Phila. 1: 59. Type material: MCZ.

Ceroptres pisum (Osten-Sacken) Osten-Sacken, 1865 . Proc. Ent. Soc. Phila. 4: 369.

Type material (examined). HOLOTYPE (♀) with the following labels: ‘Gall of C. q. pisum’ (white label, hand- written) / ‘Osten Sacken Coll.’ (white label) / ‘Type 13980’ (red label) / ‘ Ceroptres pisum O.S.’ (white label, handwritten) / ‘ MCZ Image Database’ (white label) / ‘MCZ-ENT 00013980’ (white label, QR code) / ‘ Holotype ♀ Sarothrus ? pisum Osten-Sacken, 1861 ’ (red label) / ‘ Ceroptres pisum (Osten-Sacken) Osten-Sacken, 1865 , IL-V det. 2018’ (white label).

Diagnosis. This species can be separated from the rest of Ceroptres by having a large body size, almost 4.0 mm in length (the rest of species always under 3.0 mm in length, reaching at most 3.0 mm in length in C. montensis ); body mainly black, except for a light halo around the oral fovea (face uniformly colored in the rest of species); malar space almost 0.6 times as long as height of compound eye (shorter in the rest of species, except in C. quadratifacies sp. nov., see below); and female antenna 13-segmented (males unknown), which are filiform and nearly as long as the length of the body.

Redescription. Female. Length. Body length 3.8 mm (n=1).

Color ( Figs 4f , 8 a–c). Black. Head black, except for a brownish orange halo around the oral fovea. Mesosoma black; tegulae brown. Antennae testaceous. Legs yellow, metacoxae dark basally, tip of tarsi black. Metasoma dark brown to black, terminal segments and hypopygium somewhat lighter. Wings hyaline, veins pale yellow.

Head. In anterior view ( Fig. 4f ) trapezoid-shaped, about 1.3 times as wide as high, genae not expanded behind compound eyes. Face with moderately long and dense pubescence, lower face with long striae radiating from sides of clypeus, reaching the base of compound eyes and almost the toruli; medially without striae; vertical carinae weak and incomplete, short, running just a little from inner ventral margin of the toruli (1/4 at most) and delimiting a small depressed area. Clypeus distinct, basal margin not projected over mandibles. Malar space almost 0.6 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 mid-height of compound eyes; distance between torulus and compound eye slightly shorter than diameter of the toruli; distance between the toruli shorter than diameter of the toruli. Front finely coriaceous to alutaceous, with small piliferous punctures; without frontal carinae. Head in dorsal view ( Fig. 8b ) is about 2.2 times as wide as long. Vertex finely coriaceous to alutaceous, with small piliferous punctures. POL:OOL:LOL = 18:10:8.5 and diameter of lateral ocelli, 7.5. Occiput finely coriaceous to alutaceous, without punctures.

Antennae ( Fig. 8c ). 13-segmented; a weak suture seems to split the last antennomere in two, but without delimiting two independent segments; filiform, nearly as long as the body; pubescence dense and short. Scape plus pedicel slightly longer than F1; pedicel about as long as wide; F1 about 0.7 times as long as F2, F2 and F3 subequal, the following segments progressively shorter. Last flagellar segment about 4.0 times as long as wide (28/7) and 2.3 times as long as F10.

Mesosoma. About 1.1 times as long as high in lateral view ( Fig. 8a ), including nucha, with long and moderately dense pubescence. Ratio of length of pronotum medially/laterally: 0.26. Dorsal part of pronotal plate complete, finely punctate, with two distinct foveae. Lateral pronotum finely coriaceous to alutaceous, without lateral carina. Mesoscutum ( Fig. 8b ) about 1.1 times as wide as long, with dense discontinuous transversal elements and micropunctate; anterior grooves extending some more than 1/3 of the mesoscutal length. Notauli complete and well impressed in their whole length, smooth. Parapsidal grooves surpassing tegulae. Mesoscutellum ( Fig. 8b ) slightly longer than wide, strongly wrinkled; circumscutellar carina absent; scutellar foveae subtriangular, narrow, shallow, not well defined posteriorly and separated by a narrow carina. Mesopleuron ( Fig. 8a ) smooth and shiny; little pubescent basally. Metapleural sulcus reaching about 3/4 parts of mesopleural height. Propodeum pubescent and weakly sculptured, finely coriaceous; propodeal carinae straight and parallel. Nucha weakly sculptured dorsally and laterally, not sulcate.

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

Wings ( Fig. 8d ). Forewings pubescent with short marginal setae, slightly shorter than total body length. Radial cell closed, about 2.8 times as long as wide; areolet not well defined, anterior and basal veins inconspicuous. Rs+M inconspicuous. Basal cell with sparsely spaced setae.

Metasoma ( Fig. 8a ). Shorter than head plus mesosoma and slightly longer than high in lateral view. First metasomal tergum crescent-shaped and smooth. Second metasomal tergum short and free, about 0.2 times as long as the metasomal length and faintly pubescent anterolaterally. Third metasomal tergum with a small posterodorsal patch of micropunctures, somewhat extended laterally; not dorsodistally incised. Subsequent terga and hypopygium, punctate. Prominent part of the hypopygial spine about as long as wide and just slightly projected.

Male. Unknown.

Distribution. USA. State of Washington D.C. ( Osten-Sacken 1861).

Biology. Presumably obtained from a gall of what Fitch (1859) originally called Cynips quercuspisum Fitch, 1859 (now, Ceroptres quercuspisum ( Fitch, 1859)) according to Osten-Sacken (1865: 370), on the underside of leaves of Quercus alba L. ( Quercus section ) ( Osten-Sacken 1861). Osten-Sacken (1865: 369, 370) says the gall from which C. pisum was obtained could be induced, in fact, by Acraspis pezomachoides (Osten-Sacken, 1862) .

Remarks. Ceroptres pisum was originally described from a single specimen ( Osten-Sacken 1861: 59), a female, which Osten-Sacken erroneously stated to be a male in the original description ( Osten-Sacken 1865: 369), so he redescribed it. We found and examined the only type specimen of C. pisum , which is deposited in MCZ; it is pierced through the mesosoma, thus preventing us from studying the median groove.

Figures

FIGURE 4. Female faces of valid species of Ceroptres: a) C. kovalevi (type), discontinuous lines point out vertical carinae; b) C. lanigerae (type); c) C. minutissimi (type); d) C. montensis (type); e) C. petiolicola (type); f) C. pisum (type); g) C. quercusobtusilobae (type); h) C. rufiventris (type); i) C. snellingi (type).

FIGURE 8. a) Ceroptres pisum lateral and b) dorsal habitus, c) detail of female antenna and d) forewing (type); e) C. quercusobtusilobae lateral habitus and f) mesosoma in dorsolateral view (type); g) C. rufiventris lateral and h) dorsal habitus (type).