Atrusca occidua ( Kinsey, 1936 )

Cuesta-Porta, Victor, Melika, George, Ferrer-Suay, Mar, Vera-Ortiz, Alexis & Pujade-Villar, Juli, 2025, Review of the Nearctic and Neotropical genus Atrusca Kinsey, 1930 (Hymenoptera: Cynipidae, Cynipini), Zootaxa 5617 (1), pp. 1-195 : 110-114

Atrusca occidua ( Kinsey, 1936)

Figs 344–351

Cynips ( dugesi ) occidua Kinsey, 1936: 119 , female, gall.

Atrusca occidua (Kinsey) : Weld 1952: 314.

Types examined. HOLOTYPE female Cynips ( dugesi ) occidua “La Mesa Zac 7000’, Mex. Gall 11.21.31, 5 fms. 11.30.31”, “ Q. depressipes, Kinsey coll.”, red “ Cynips occidua , Holo- Paratype ”, deposited in AMNH, NYC, examined by GM. 119 PARATYPES were designated by Kinsey, deposited in the general collection of AMNH, 10 of them were examined by GM.

Diagnosis. Atrusca occidua belongs to the species group characterized by a reddish brown body color, lacking dark stripes in the mesoscutum, exhibiting fore wings with a complete and conspicuous venation, the Rs vein of radial cell being strongly curved distally, never almost straight, the entirely rugose mesoscutellum, the mesopleuron and speculum sculptured in varying proportions, without any linear sculpture and with or without piliferous points, and the ventral spine of the hypopygium is setose, with setae extending beyond the apex of the spine, as in A. oriens , A. pupoides , A. spadix , and A. vasta . Atrusca occidua differs from A. oriens , A. pupoides , A. spadix , and A. vasta by the uniformly alutaceous mesopleuron and speculum, ans the Rs vein strongly angulated distally, while in A. oriens , A. pupoides , A. spadix , and A. vasta the mesopleuron features smooth areas, the speculum may be sculptured or not, and the Rs vein is arcuate, sometimes slightly angulated distally.

Re-description. Asexual female ( Figs 344–350 ). The species description is combined from Kinsey (1936: 119) and our observations of the type photos.

Head, antenna, mesosoma, legs, dark reddish brown, mesoscutum with darker brown stripes along anterior parallel and parapsidal lines; metasoma reddish brown, second metasomal tergum with black band posteriorly.

Head ovate in frontal view, alutaceous, with sparse white setae, 1.4× as broad as high and narrower than mesosoma in frontal view, 2.3× 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, without striae radiating from clypeus; malar sulcus absent; eye 2.5× as high as height of malar space. Inner margins of eyes slightly diverging ventrally. POL 1.2× as long as OOL; OOL 1.8× as long as diameter of lateral ocellus and 1.8× as long as LOL; all ocelli rounded, of same size. Transfacial distance 1.2× as long as height of eye and 1.7× as long as height of as lower face; diameter of antennal torulus 1.5× as long as distance between them, distance between torulus and eye equal to diameter of torulus; lower face alutaceous, shining along eye, dull rugose in central part, below toruli and area between toruli, with white setae; slightly elevated median area rugose, without setae. Interocellar area slightly elevated above head in frontal view, lateral ocelli prominent. Clypeus trapezoid, impressed, smooth, shining, broader than high, with a 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 alutaceous-reticulate, with few short setae, denser in the interocellar area; small rounded, smooth, shining impression present under central ocellus. Antenna slightly shorter than length of body, with 12 flagellomeres, pedicel 1.4× as long as broad, F1 as long as scape+pedicel and 1.1× as long as F2; F2 1.2× as long as F3; F3 shorter F2 and slightly longer than F4, F4 1.3× as long as F5, F6 shorter than F7, F7=F8, subsequent flagellomeres shorter, nearly equal in length, F12 1.3× as long as F11.

Mesosoma 1.1× as long as high, with white setae. Pronotum in lateral view coriaceous, with short parallel striae along posterior edge. Mesoscutum coriaceous to delicately rugose in anterior 1/3, with uniformly distributed piliferous points, with sparse white setae, denser aside notaulus; slightly longer than broad (greatest width measured across mesoscutum at level of base of tegulae). Notaulus complete, deep, broad, with smooth, shining bottom, posteriorly broader and slightly converging; anterior parallel impressed in anterior 1/3 of mesoscutum length, with darker stripes along them, extending to half length of mesoscutum; and parapsidal line indistinct, indicated by smooth darker stripe; median mesoscutal line present in the posterior 1/4 of mesoscutum length; parascutal carina narrow, smooth, reaching notaulus. Mesoscutellum ovate, elongated, uniformly rugose, with dull rugae laterally, with subparallel sides; posteriorly rounded, not invaginated posterocentrally; overhanging metanotum; mesoscutellar foveae transverse, broader than high, with smooth, shining bottom and longitudinal rugae, separated by a narrow elevated central carina. Circumscutellar carina complete. Mesopleuron and speculum uniformly alutaceous, with a few setae, especially ventrally; mesopleural triangle smooth, shining, with some irregular rugae and few setae; dorsal and lateral axillar areas coriaceous, shining, with dense setae; metapleural sulcus reaching mesopleuron at half height, upper part of sulcus distinct. Metascutellum with longitudinal parallel delicate sulci, slightly higher than height of smooth, shining ventral impressed area; metanotal trough smooth, shining, without setae; central propodeal area with strong irregular short rugae, shining; lateral propodeal carinae strong, broad and elevated, strongly bent outwards in posterior 1/3; lateral propodeal area delicately coriaceous, shining, with long dense white setae, with some short irregular rugae. Nucha with irregular sulci laterally and dorsally. Tarsal claws toothed, with basal lobe.

Fore wing longer than body, normal size, margin with long dense cilia, with few slightly darker spots and stripes, wing infuscated along veins, veins dark brown, radial cell open, 1.6× as long as broad; second abscissa of Rs strongly curved distally; R1 and Rs nearly reaching wing margin; areolet triangular, indistinct, Rs+M inconspicuous, hardly traceable along entire length, its projection reaching basalis in the lower 1/3 of its height.

Metasoma slightly longer than head+mesosoma, longer than than high in lateral view; second metasomal tergum extending to 4/5 of metasoma length 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 3.0× as long as broad in ventral view, with long setae ventrally which extend beyond apex of spine.

Body length 2.2–3.0 mm ( Kinsey 1936).

Gall ( Fig. 351 ). The gall is similar to all galls of Kinsey’s bella and dugesi complexes. Mature galls yellowish or bright rosy tan, younger galls richer rose, unspotted, smooth, shining tu dull matte, thin walled, up to 24 mmm, in average 21 mm in diameter.

Biology. The asexual generation is only known to induce leaf galls on Q. depressipes , Q. potosina . Galls mature in late autumn; adults emerge in January–February next year.

Distribution. Mexico: Zacatecas.

Figures

FIGURE 351. Atrusca occidua (Kinsey, 1936), galls. Pictures are taken from the Kinsey holotype collection in AMNH, NYC by Mar Ferrer-Suay.

FIGURES 344–345. Atrusca occidua (Kinsey, 1936), asexual female, holotype. 344, general habitus, lateral view. 345, fore wing. Pictures are taken from the Kinsey holotype collection in AMNH, NYC by Mar Ferrer-Suay.

FIGURES 346–350. Atrusca occidua (Kinsey, 1936), asexual female, holotype. 346–347, general habitus, part: 346, lateral view, 347, dorsal view. 348, head and mesosoma, dorsal view. 349, head and mesosoma, part, frontal view. 350, metascutellum and propodeum, posterodorsal view. Pictures are taken from the Kinsey holotype collection in AMNH, NYC by Mar Ferrer- Suay.