Archips Hübner
Type species: xylosteana Linnaeus
DIAGNOSIS
External characters:
Venation:
venation Archips podana
Forewing: All veins are separate; Sc long; R 4 to before costa; median cell with weak internal vein; CuP atrophying in anterior half.
Hindwing: Somewhat variable as M 3-CuA 1 can be separate, from one point or very short stalked.
Forewing shape and markings
examples of Archips adults
Species of the genus Archips have relatively broad forewings; often either the termen or the costa, or both, are somewhat concave before or beyond apex. In males, the forewings have a costal fold. The ground colour is yellowish to brownish in the majority of the species, often with a reddish, pinkish or purplish admixture. The markings are very variable, and often greatly reduced in females. In males, the basal patch is often only expressed dorsally.
Sexual dimorphism:
In males, the antennae are delicately dentate, in females they are simple. Sexual dimorphism also expressed in size and colouration. Females are much larger than males and their markings are more or less reduced. The forewing of the male is usually expands more terminally, and is provided with a costal fold; while in females the termen is usually more strongly concave beyond apex, the latter being longer and more pronounced. On the female hindwing, a group of scent scales can be found near the apex.
Additional characters:
On the second and third tergites or, rarely, from the second to the sixth tergites, occur pairs of pits of unknown importance. These can also be found on pupae. These dorsal pits are pairs of round or reniform cavities, situated on either side of the median line, separated from each other by a ridge. The first pair is partially hidden by flanged plates developed from the first and second tergites, the second pair by similar plates of the second and third tergites.
Genitalia:
Male:
male genitalia A. xylosteana ; male genitalia A. machlopis
Uncus usually slender, often club-shaped, in some species broad, exceptionally bifurcate; gnathos arm slender, terminal plate elongate, sharp; socius very small or rudimentary; tegumen large, with small ventral sclerites. Valva ovate or subtriangular, the dorsal part of which is minutely folded radially, scaled and hairy; pulvinus distinct; sacculus species specific, with spined or smooth free termination, expanding beyond base ventrally. Transtilla band-shaped, folded upwards in middle, broad laterally; juxta simple, rather small. Aedeagus simple or with process; cornuti numerous, long spines; constant number of cornuti never found.
Female:
female gen. A. xylosteana ; female gen. A. oporana
Sterigma more or less elongate, usually with well developed cup-shaped portion anteriorly, fusing with antrum, provided with submedian areas of scent scales; antrum sclerite distinct, surrounded by broadened membrane; ductus seminalis extending from antrum; ductus bursae long; cestum variably long, extending from beyond corpus bursae, exceptionally absent; capitulum of signum and basal plates distinct. Subgenital sternite variably incised in middle posteriorly, provided with specific prominences or folds.
Early stages:
Non-hibernation eggs are usually oval and greenish in colour; egg masses imbricate. Full-grown larvae are 15-30 mm long and usually have a well-developed anal comb. Swatschek, 1958, provides the following diagnosis based on chaetotaxy of 5 Palaearctic species. He however also included two species of Choristoneura in his studies.
SV group on abdominal segments 1, 2 and 7 trisetose, bisetose on the eighth and ninth. On the mesothorax, V1 is clearly distanced from coxa and SD2 is situated antero-dorsally to SD1. The spiracle on the second abdominal segment is clearly bigger than the basal ring of seta SD1, and the spiracles of the prothorax and the eighth abdominal segment are very large. The second stemma is equidistant from first and third. On the prothorax, the distance between setae L3 and L1 is twice as long as that between setae L1 and L2.
Pupae are dark-brown to blackish in colour and have an elongated cremaster. In many species, dorsal pits are present.
Biology:
Hibernation occurs either in egg stage or in third, rarely second instar larvae.
The species hibernating in egg stage are probably constantly univoltine, other species occur in two to three, or even exceptionally in more generations, yearly. First instar larvae are oligophagous, the older larvae may live polyphagously. The host plants are mainly deciduous trees and bushes, but also conifers.
Distribution:
The genus occurs in the Palaearctic, Nearctic and Oriental Regions.