Atrusca spinalis ( Kinsey, 1936 )

Atrusca spinalis ( Kinsey, 1936)

Figs 516–529 View FIGURES 516–521 View FIGURES 522–525 View FIGURES 526–529

Cynips View in CoL ( dugesi ) spinalis Kinsey, 1936: 136 , female, gall.

Atrusca spinalis (Kinsey) : Weld 1952: 315.

Types examined. HOLOTYPE female Cynips View in CoL ( dugesi ) spinalis “Cuernavaca 8N Mor. 8700’, Mex. Gall 1.7.32, 24 fms. 1.25.32”, “ Q. texcocana, Kinsey View in CoL coll.”, red “ Cynips spinalis , Holo- Paratype ”, deposited in AMNH, NYC, examined by GM. Two PARATYPE females “Cuernavaca, 8N, Mor 8700’, Mex., galls 1.7.32, 24 females 1.25.32”, “ Q. texcocana Kinsey View in CoL coll.” red label “ Cynips spinalis Paratype ”, deposited in the general collection in AMNH, NYC, examined by GM.

Diagnosis. Atrusca spinalis is characterized by a reddish-brown body, the head rounded or quadrangular in frontal view, the interocellar area not elevated above head in frontal view but lateral ocelli are prominent in lateral view, the fore wings with complete venation, and Rs gradually curved in the radial cell, almost straight, the pronotum exhibits distinct irregular rugae laterally, and the mesoscutum is uniformly coriaceous, the mesoscutellum is rounded posteriorly, and the ventral spine of hypopygium long, 9.2–11.3× as long as broad, as in A. spinescens . Atrusca spinalis differs from A. spinescens by the uniformly colored mesoscutum, the presence of a short, impressed mesoscutal median line, and the mesoscutellar foveae being smooth, separated by a central area delimited by two carinae. In contrast, A. spinescens has darker brown stripes along the anterior parallel and parapsidal lines, lacks the median mesoscutal line entirely, and the mesoscutellar foveae display irregular short rugae, and are separated by a narrow elevated central carina.

Re-description. Asexual female ( Figs 516–528 View FIGURES 516–521 View FIGURES 522–525 View FIGURES 526–529 ). Head, antenna, mesosoma, legs uniformly reddish brown, mesoscutum without darker stripes, metasoma slightly lighter with black band posteriorly.

Head more or less circular in frontal view, alutaceous, with sparse white setae, denser along inner sides of eyes, 1.2× as broad as high and narrower than mesosoma in frontal view, 1.6× as broad as long in dorsal view. Gena alutaceous, slightly broadened behind eye in frontal view, narrower than transverse diameter of eye in lateral view. Malar space alutaceous, without striae; malar sulcus absent; eye 2.3× as high as height of malar space. Inner margins of eyes diverging ventrally. POL 2.3× as long as OOL; OOL 1.1× as long as diameter of lateral ocellus and equal to LOL; all ocelli ovate, of same size. Transfacial distance 1.1× as long as height of eye and 1.4× as long as height of lower face; diameter of antennal torulus 2.3× as long as distance between them, distance between torulus and eye shorter than diameter of torulus; lower face alutaceous, with dense setae, without striae; slightly elevated median area coriaceous, with setae. Area between toruli and torulus eye delicately coriaceous. Interocellar area elevated above head in frontal view, lateral ocelli prominent. Clypeus impressed, uniformly alutaceous, rectangular, broader than high, with few long setae; ventrally rounded, emarginate, without median incision; anterior tentorial pit large, rounded, epistomal sulcus and clypeo-pleurostomal line broad, well impressed. Frons and interocellar area rugose, with few short setae. Vertex, occiput alutaceous, with sparse white setae; postocciput, postgena smooth, shining; posterior tentorial pit large, ovate, area below impressed; occipital foramen as high as height of postgenal bridge; hypostomal carina emarginate, continuing into postgenal sulci which run parallel ventrally, bent outwards dorsally towards occipital foramen, postgenal bridge dorsally broader than ventrally and broader than width of occipital foramen. Antenna slightly longer than head+mesosoma, with 12 flagellomeres, pedicel broader than long, F1 1.3× as long as scape+pedicel and 1.1× as long as F2; F2 0.8× as long as F3; F3 1.2× as long as F4, subsequent flagellomeres progressively shorter, F12 longer than F11; placodeal sensilla on F6–F12.

Mesosoma 1.3× as long as high, with sparse short white setae. Pronotum delicately uniformly coriaceous, laterally with parallel delicate striae posteriorly extending to half width of pronotum; propleuron alutaceous, shining. Mesoscutum uniformly delicately and uniformely coriaceous, with piliferous points, dense white setae; slightly longer than broad (greatest width measured across mesoscutum at level of base of tegulae). Notaulus complete, deep, broad, with smooth, glabrous bottom, posteriorly broader and slightly converging; anterior parallel line slightly impressed in most anterior part, parapsidal line indistinct, hardly traceable, indicated by smooth stripe; median mesoscutal line present in a form of short impressed triangle; parascutal carina narrow, smooth, reaching notaulus. Mesoscutellum trapezoid, broader in posterior 1/3, rounded posteriorly or gradually narrowing to central point, without invagination, uniformly dull rugose; overhanging metanotum; mesoscutellar foveae quadrangular, nearly as broad as high, with smooth, shining bottom, separated by broad elevated coriaceous central carina. Circumscutellar carina complete. Mesopleuron and speculum smooth, shining, with a few setae; mesopleural triangle smooth, shining, with some irregular striae and some setae; dorsal and lateral axillar areas smooth, shining, with white short setae; subaxillular bar smooth, shining, most posterior part slightly higher than height of metanotal trough; metapleural sulcus reaching mesopleuron slightly above its midheight, upper part of sulcus indistinct. Metascutellum coriaceous, with some rugae, higher than height of smooth, glabrous ventral impressed area; metanotal trough smooth, shining, without setae; central propodeal area smooth, shining, with few longitudinal rugae laterally in posterior part; lateral propodeal carinae strongly bent outwards in posterior 1/4 of propodeum height; lateral propodeal area smooth, shining, with irregular strong rugae and sparse white setae. Nucha with delicate sulci laterally, smooth, shining dorsocentrally. Tarsal claws toothed, with basal lobe.

Fore wing longer than body, shorter than normal size, margin with long dense cilia, with slightly darker spots and stripes, wing infuscated, veins dark brown, radial cell open, 2.6× as long as broad; second abscissa of Rs gradually curved not angled distally; R1 and Rs nearly reaching wing margin; areolet triangular, distinct, Rs+M inconspicuous, hardly traceable along entire length, reaching basalis at its mid height.

Metasoma longer than head+mesosoma, slightly higher than long in lateral view; second metasomal tergum extending 2/3 metasoma length of in dorsal view, with white setae anterolaterally, without band of micropunctures posteriorly; subsequent terga without micropunctures, without setae. Hypopygium without micropunctures, prominent part of ventral spine of hypopygium 9.2× as long as broad in ventral view, with setae which extend beyond apex of spine.

Body length 3.0–4.0 mm ( Kinsey 1936).

Gall ( Fig. 529 View FIGURES 526–529 ). The gall is similar to all galls of Kinsey’s bella and dugesi complexes. Mature galls very light olive tan, less often rosy, unspotted, smooth, shining, often bluish puberulent, up to 16 mm, in average 13 mm in diameter.

Biology. The asexual generation is only known to induce leaf galls on Q. deserticola (= Q. texcocana ). Galls mature in late autumn; adults emerge from January next year.

Distribution. Mexico: Morelos.