Ceroptres snellingi Lyon, 1996

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 : 52-56

Ceroptres snellingi Lyon, 1996

( Figures 4i ; 9 a–b; 17a–l; 18a, i, j, l, u)

Ceropteres snellingi Lyon, 1996 . Pan-Pac., Entomol. 72(4): 182 [Miswritten]. Type material: USNM (holotype), paratypes in USNM, CAS, NHMLA and R. J. Lyon collection.

Ceroptres snellingi Lyon, 1996 [Generic name corrected here].

Type material (examined). HOLOTYPE (♀) with the following labels: ‘El Paso, TX., FEB. 15, 1969 ’ (white label) / ‘Exit Andricus flocculentus Lyon’ (white label, handwritten) / ‘Q. pungens’ (white label) / ‘ Holotype, Ceropteres snellingi Lyon’ (white label with a red frame, handwritten) / ‘USNMENT 00802338’ (white label, QR code). PARA- TYPES (6♂ & 9♀) deposited in CAS with the following labels: ‘ El Paso, TX., FEB. 15, 1969 ’ (white label) / ‘Exit Andricus flocculentus Lyon’ (white label, handwritten) / ‘Q. pungens’ (white label) / ‘good’ (pink label) / ‘ Paratype Ceroptres snellingi Lyon, R. J. Lyon’ (yellow label) (9♀); same labels, except for the pink one: 6♂.

Additional material (16♂ & 15♀). New material collected in Mexico and deposited in UB with the following location data: STATE OF AGUASCALIENTES: MEX: P366 (Clark-15), Peñón Blanco (San José de Gracia, AGS), 22°10’11.91” N, 102°31’14.68” W, Ex. unknown leaf petiole gall, 2300m, Q. potosina , (12.xii.2011) i-ii.2012, R. Clark leg.: 3♂ & 3♀. STATE OF CIUDAD DE MÉXICO: MEX: 072, P.N. del Bosque del Pedregal ( CDMX), 19º17’22.4’’ N, 99º11’35.36’’ W, Ex. gall of Andricus sphaericus, 2400m , Q. mexicana , (16.vii.2011) 13.viii.2011, M. Serrano leg.: 1♂. STATE OF MÉXICO: MEX: 312 (verde 65), Tunal-El Salto (San Felipe del progreso, EDO. MEX.), 19°42’53.28’’ N, 99°57’10.08’’ W, Andricus group georgei, 2650m , Quercus sp., (22.iii.2014) 11.v.2014, Delia leg.: 1♀. STATE OF NUEVO LEÓN: MEX: 307, near Santa Catarina ( NL), Andricus sphaericus , Q. rugosa ,

(04.vii.2014) 11.vii.2014, A. Equihua & E. Estrada: 1♀. STATE OF ZACATECAS: MEX: 069, La Herradura (Mon- te Escobedo, ZAC), 22°13’24.41’’ N, 103°30’18.91’’ W, Ex. gall of an undescribed species of Andricus, 1913m , Q. eduardi cf, (01.viii.2011) 04.viii.2011, O. Cabral, R. Treto, L.G. Landa and C. Carrillo leg.: 8♂ & 7♀; MEX: P015, Santiago de la Herradura (Sombrerete, ZAC), 23°48’8.55’’ N, 103°34’40.91’’ W, Ex. gall of an undescribed species of Andricus, 2293m , Q. chihuahuensis cf, (01.viii.2011) viii.2011, C. Carrillo leg.: 4♂ & 3♀. Also, 3♂ & 3♀ of MEX: 069 dissected and gold coated.

Diagnosis. Ceroptres snellingi is morphologically similar to C. quercusobtusilobae , from which it can be distinguished by the sculpture of the mesoscutum (coriaceous with some small punctures in C. snellingi , alutaceous with some weak discontinuous transversal elements in C. quercusobtusilobae ) and the mesoscutellum (anteriorly and medially strongly coriaceous to weakly wrinkled, with interspaces coriaceous in C. snellingi ; moderately strong and densely wrinkled, with interspaces alutaceous, in C. quercusobtusilobae ); the length of the hypopygial spine (1.7 times as wide as long in C. snellingi and 1.3 in C. quercusobtusilobae ), among others (see the descriptions of both species and the key to valid species of Ceroptres ).

Redescription. Female. Length. Body length 1.2–2.1 mm (n=22).

Color ( Figs 4i , 9 a–b). Mainly black or reddish dark brown. Head and mesosoma black or reddish dark brown; tegulae amber to testaceous. Antennae amber to testaceous, tips sometimes somewhat darker. Legs with coxae and femorae more or less dusky to black, tarsi infuscated, the rest dark yellow. Metasoma dark brown or chestnut to black; hypopygium yellowish, somewhat dusky. Wings hyaline, veins pale yellow.

Head. In anterior view ( Fig. 17a ) round-shaped, almost 1.2 times as wide as high, genae not expanded behind compound eyes. Face with moderately long but no dense pubescence, lower face with moderately long striae radiating from sides of clypeus, reaching the base of compound eyes but not the toruli; medially without striae; vertical carinae incomplete and weak, short, running just a little from inner ventral margin of the toruli, at most 1/ 3 in some specimens, and delimiting a depressed area that is slightly bulged just above the clypeus. Clypeus distinct, ventral margin not projected over mandibles. Malar space about 0.5 times as long as height of compound eye. Anterior tentorial pits visible; pleurostomal sulcus absent, epistomal sulcus slightly impressed. Transfacial line about 0.9 times as long as height of compound eye. Toruli situated mid-height of compound eye; distance between torulus and compound eye slightly shorter than diameter of the toruli; distance between the toruli clearly shorter than diameter of the toruli. Front finely coriaceous to alutaceous, shiny, sometimes with a few and small punctures; without frontal carinae. Head in dorsal view ( Fig. 17b ) is about 2.0 times as wide as long (wider in some specimens). Vertex finely coriaceous to alutaceous, shiny, without punctures (or just with a few and small punctures). POL:OOL:LOL = 10:5:5; POL about 2.0 times as long as OOL, shorter in some specimens; OOL about 1.7 times as long as diameter of lateral ocelli, shorter or longer in some specimens. Occiput finely coriaceous to alutaceous, without punctures.

Antennae ( Fig. 17e ). 12-segmented; subclavate, just slightly broadened apically; pubescence dense and short. Scape plus pedicel about 1.3 as long as F1; pedicel about 1.3 times as long as wide; F1 about 0.9 times as long as F2, F2 and F3 subequal, the following segments progressively shorter. Last flagellar segment about 3.5 times as long as wide and about 2.0 times as long as F9.

Mesosoma. About 1.3 times as long as high in lateral view ( Fig. 17h ), including nucha, with long, but not dense, pubescence. Ratio of length of pronotum medially/laterally: 0.4. Dorsal part of pronotal plate complete, with two distinct closely spaced foveae. Lateral pronotum alutaceous, without lateral carina. Mesoscutum ( Fig. 17g ) just slightly wider than long, coriaceous and posteriorly with scarce small piliferous punctures; anterior grooves weakly impressed, extending 1/3 of the mesoscutal length. Notauli almost complete, but faint in the anterior 1/3 or before reaching the pronotal margin. Parapsidal grooves weakly impressed or inconspicuous. Median groove short and shallow, visible at most in the posterior 1/3 of the mesoscutum in some specimens (sometimes in a form of short incision). Mesoscutellum ( Fig. 17g ) rounded, about as long as wide, anteriorly and medially strongly coriaceous to weakly wrinkled, wrinkled laterally and posteriorly, interspaces coriaceous; circumscutellar carina absent; scutellar foveae small, subtriangular to ovate, shallow, not well defined posteriorly, weakly sculptured and separated by a narrow carina. Mesopleuron ( Fig. 17h ) smooth and shiny; little pubescent basally. Metapleural sulcus well defined, reaching about 4/5 parts of the mesopleural height. Propodeum ( Fig. 17k ) pubescent and smooth; propodeal carinae straight and slightly branched in the posterior 1/3. Nucha weakly sulcate dorsally and laterally.

Legs. Tarsal claws bidentate, with a basal lobe ( Fig. 17j ).

Wings. Forewings pubescent with moderately long marginal setae, longer than total body length ( Fig. 9a ). Radial cell closed, about 2.7 times as long as wide ( Fig. 17l ); areolet not well defined, anterior and basal veins inconspicuous. Rs+M inconspicuous. Basal cell with sparsely spaced setae.

Metasoma ( Figs 9a , 17i ). Slightly shorter than head plus mesosoma, slightly longer than high in lateral view. First metasomal tergum crescent-shaped and smooth. Second metasomal tergum short and free, 0.3 times as long as the metasomal length and with a dense hair patch anterolaterally. Third metasomal tergum without micropunctures (or just with a few, almost inconspicuous, micropunctures not forming a true patch) and not dorsodistally incised; subsequent terga very finely punctate. Hypopygium slightly projected above the upper surface of the metasoma. Prominent part of the hypopygial spine 1.7 times as long as wide and slightly projected.

Male ( Fig. 17c, d, f )

Similar to female, except for the following morphological traits: body length 1.0–2.0 mm (n=19). Antennae 15- segmented, filiform; pedicel about as long as wide; F1 not expanded apically, conical; the 14 th and 15 th sometimes inconspicuously separated ( Fig. 17f , inset image); last flagellar segment almost 3.0 times as long as wide and just slightly longer than the penultimate. OOL about as long as the diameter of the lateral ocelli in some specimens (ocelli bigger than in females). Vertical carinae extending 1/3 from inner ventral margin of the toruli and slightly more marked. Notauli usually more deeply impressed and extended. Radial cell slightly shorter than in females (2.6) and wing veins usually darker. Legs somewhat paler, almost entirely yellow in some specimens.

Distribution. USA (state of Texas) ( Lyon 1996) and Mexico (states of Aguascalientes, Ciudad de México, México, Nuevo León and Zacatecas) (in this work, see the additional material).

Biology. Originally reared from leaf galls of Andricus flocculentus Lyon, 1996 on Quercus pungens Liebm. ( Quercus section ) ( Lyon 1996). The new material collected in Mexico has been obtained from galls of Andricus sphaericus on Quercus mexicana Bonpl. (Lobatae section) and Q. rugosa ( Quercus section ) ( Fig. 18i ); from an undescribed species of Andricus on leaves of Quercus cf chihuahuensis Trel. ( Quercus section ) ( Fig. 18l ) and Quercus cf eduardi Trel. (Lobatae section) ( Fig. 18a ); from an unknown leaf petiole gall on Q. potosina Trel. ( Quercus section ) ( Fig. 18u ); and from a gall of Andricus belonging to the georgei group on an undetermined oak ( Fig. 18j ) (in this work, see the additional material).

Remarks. Ceroptres snellingi was originally described from 18 specimens ( Lyon 1996: 182). We examined the holotype deposited in USNM, as well as 15 paratypes (6♂ and 9♀) deposited in CAS.

According to Lyon (1996), males of C. snellingi have 14-segmented antennae, but all the males examined, both from the types series and from new material collected in Mexico, have 15-segmented antennae; however, the 14 th and 15 th segments are sometimes inconspicuously separated ( Fig. 17f , inset image), which could lead Lyon to think they have 14 segments instead of 15.

This species displays a moderate degree of morphological variability, especially regarding the length of the pedicel, ocellar ratios, body color (specimens from Mexico are darker than Lyon’s types) and F1/F2 ratio, even within specimens obtained from the same gall. However, since these are just subtle differences we consider all the specimens as the same species.

Ceroptres snellingi was published as ‘ Ceropteres ’, clearly a miswriting of Ceroptres , and as a result doesnot appearing in any previously published work. We here rectify the name to Ceroptres snellingi Lyon, 1996 .

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 9. a) Ceroptres snellingi lateral and b) dorsal habitus (type).

FIGURE 17. Ceroptres snellingi (material from Mexico): a) female head in anterior view; b) female head in dorsal view; c) male head in anterior view; d) male head in dorsal view; e) female antenna; f) male antenna (with a detail of the last segments, inset image); g) mesosoma in dorsal view; h) mesosoma in lateral view; i) female metasoma in lateral view; j) tarsal claws; k) propodeum; l) radial cell of the forewing.

FIGURE 18. Some of the galls mentioned in this study: a) an undescribed species of Andricus (ref. 069); b) Sphaeroteras nr pulchripennis (ref. 103); c) Dros perlentum (ref. 123); d) Neuroterus eugeros (ref. 182); e) Andricus georgei (ref. 206); f) unknown leaf gall of Neuroterus (ref. 225); g) unknown leaf spherical gall (ref. 266); h) Andricus sphaericus (ref. 303); i) Andricus sphaericus (ref. 307); j) Andricus group georgei (ref. 312); k) Melikaiella amphibolensis (ref. 338); l) an undescribed species of Andricus on leaves (ref. P015); m) Atrusca sp. (ref. P149); n) unknown (P225); o) unknown undetachable leaf gall (ref. P233); p) unknown gall inside secondary leaf nerves (ref. P307); q) Atrusca pictor (ref. P322); r) Atrusca sp. (ref. P328); s) unknown (ref. 2B10, 13B6); t) unknown, a mix of galls (ref. 2840); u) unknown leaf petiole gall (ref. P366); v) unknown twig gall (ref. P308).