Atrusca spinescens ( Kinsey, 1936 )

Atrusca spinescens ( Kinsey, 1936)

Figs 530–543 View FIGURES 530–535 View FIGURES 536–539 View FIGURES 540–543

Cynips View in CoL ( dugesi ) spinescens Kinsey, 1936: 137 , female, gall.

Atrusca spinescens (Kinsey) : Weld 1952: 315.

Types examined. HOLOTYPE female Cynips View in CoL ( dugesi ) spinescens “Jilotepec 7NW Mex. 9500’, Mex. Gall 1.16.32, 6 fms. 3.6.32”, “ Q. purpusi, Kinsey coll.”, red “ Cynips spinescens , Holo- Paratype ”, deposited in AMNH, NYC, examined by GM. One PARATYPE females “Jilotepec, 7NW, Mex 9500’, Mex., galls 1.16.32, 6 females 3.6.32”, “ Q. purpusi Kinsey coll.” red label “ Cynips spinescens Paratype ”, deposited in the general collection in AMNH, NYC, examined by GM.

Diagnosis. Atrusca spinescens 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. spinalis . Atrusca spinescens differs from A. spinalis by the presence of darker brown stripes along the anterior parallel and parapsidal lines, the lack of the median mesoscutal line entirely, and the mesoscutellar foveae display irregular short rugae, and are separated by a narrow elevated central carina, while A. spinalis exhibits uniformly colored mesoscutum, the presence of a short, impressed mesoscutal median line, and the mesoscutellar foveae smooth, separated by a central area delimited by two carinae.

Re-description. Asexual female ( Figs 530–542 View FIGURES 530–535 View FIGURES 536–539 View FIGURES 540–543 ). Head, antenna, legs uniformly reddish brown, mesoscutum with dark stripes along anterior parallel and parapsidal lines; mesosoma reddish brown with mesopleuron partially black, metasoma slightly lighter with black band posteriorly.

Head oval in frontal view, alutaceous, with sparse white setae, denser on lower face, 1.3× as broad as high and narrower than mesosoma in frontal view, 1.9× as broad as long in dorsal view. Gena alutaceous, not broadened behind eye in frontal view, narrower than transverse diameter of eye in lateral view. Malar space alutaceous-reticulate, without striae; malar sulcus absent; eye 2.3× as high as height of malar space. Inner margins of eyes slightly diverging ventrally. POL 1.9× as long as OOL; OOL 1.6× as long as diameter of lateral ocellus and 1.9× as long as LOL; all ocelli ovate, of same size. Transfacial distance 1.2× as long as height of eye and 1.7× as long as height of lower face; diameter of antennal torulus 1.4× as long as distance between them, distance between torulus and eye equal to diameter of torulus; lower face alutaceous along eyes, dull rugose centrally, under toruli, with few setae; slightly elevated median area rugose, shining, without setae. Interocellar area not elevated above head in frontal view. Clypeus impressed, uniformly delicately coriaceous with rare piliferous points, rectangular, broader than high, with few long setae; ventrally rounded, emarginate, with weak median incision; anterior tentorial pit large, rounded, epistomal sulcus and clypeo-pleurostomal line broad, well impressed. Frons and interocellar area dull rugose, with strong rugae, with few short setae. Vertex, occiput delicately coriaceous; postocciput, postgena smooth, shining with sparse white setae; posterior tentorial pit large, ovate, area below impressed; occipital foramen slightly higher than height of postgenal bridge; hypostomal carina emarginate, continuing into postgenal sulci which run towards occipital foramen, dorsally bent outwards, postgenal bridge smooth, shining, anteriorly broader than posteriorly and slightly broader than width of occipital foramen.Antenna slightly longer than head+mesosoma, with 12 flagellomeres, pedicel broader than long, F1 longer than scape+pedicel and 1.2× as long as F2; F2 slightly longer than F3; F3 1.1× as long as F4, subsequent flagellomeres progressively shorter, F12 longer than F11; placodeal sensilla on F6–F12.

Mesosoma 1.2× as long as high, with sparse short white setae. Pronotum rugose, with distinct transverse parallel rugae laterally, with sparse setae; propleuron alutaceous, shining. Mesoscutum uniformly alutaceous-reticulate, with piliferous points and white setae, denser anteriorly; 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 lines impressed, extending to half length of mesoscutum, with darker stripes; parapsidal lines impressed, with smooth stripes; median mesoscutal line absent; parascutal carina narrow, smooth, reaching notaulus. Mesoscutellum uniformly dull rugose, longer that broad, rounded posteriorly or slightly invaginated central part; overhanging metanotum; mesoscutellar foveae smooth, shining, with irregular short rugae, semilunar, transverse, broader than high, separated by narrow elevated central carina, transverse, broader than high, with bottom. Circumscutellar carina complete. Mesopleuron and speculum smooth, shining, with piliferous points and sparse setae, mesopleural triangle rugose, shining, with irregular rugae and some setae; dorsal and lateral axillar areas rugose, shining, with dense setae; subaxillular bar smooth, shining, most posterior part narrow, shorter than height of metanotal trough; metapleural sulcus reaching mesopleuron slightly above mid height, upper part of sulcus distinct. Metascutellum delicately coriaceous, as high as height of smooth, glabrous ventral impressed area; metanotal trough smooth, shining, with sparse setae; central propodeal area smooth, shining, without rugae; lateral propodeal carinae acutely bent outwards in posterior 1/3; lateral propodeal area smooth to partially alutaceous, shining, with long dense 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, 2.5× as long as broad; second abscissa of Rs gradually curved not angulated distally; R1 and Rs nearly reaching wing margin; areolet triangular, distinct, Rs+M inconspicuous, hardly traceable along entire length, reaching basalis slightly below its mid height.

Metasoma longer than head+mesosoma, higher than long in lateral view; second metasomal tergum extending 1/2 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 9.6× as long as broad in ventral view, with setae extending beyond apex of spine.

Body length 2.5–3.5 mm ( Kinsey 1936).

Gall ( Fig. 543 View FIGURES 540–543 ). The gall is similar to all galls of Kinsey’s bella and dugesi complexes. Mature galls in part light yellowish tan and in part rich rosy or purplish brown, usually well marked with purple spot sor streaks, with traces of bluish bloom, up to 19 mm, in average 14 mm in diameter.

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

Distribution. Mexico: Jilotepec.