KEYS    About TortAI    Fact Sheets    Glossary    ID Thumbnails    DNA Search    Dissection Guides Acleris variana << Previous Next >> CAPS Non-target - Adult Acleris variana (Fernald) (Tortricidae: Tortricinae: Tortricini) Common names: eastern blackheaded budworm Synonyms: angusana (Peronea) Fig. 1: Adult Fig. 1: Adult Fig. 2: Adult Fig. 2: Adult Fig. 3: Adult Fig. 3: Adult Fig. 4: Forewing patterns Fig. 4: Forewing patterns Fig. 5: Male genitalia Fig. 5: Male genitalia Fig. 6: Female genitalia Fig. 6: Female genitalia Fig. 7: Early instar larva Fig. 7: Early instar larva Fig. 8: Late instar larva Fig. 8: Late instar larva Adult Recognition FWL: 7.5-9.5 mm The forewing pattern of A. variana is quite variable and many forms are shared with Acleris gloverana. Powell (1962) describes eight different forms for A. gloverana and an additional form for A. variana. The most common forms are illustrated here. Males lack a forewing costal fold. Acleris variana is nearly identical to Acleris gloverana in both biology and morphology. The two species are geographically separated: A. gloverana occurs in western North America and A. variana occurs in eastern North America. Powell (1962) outlined minor genitalic differences that can be used to separate the two species. In males, the sacculus is broader and less elongate in A. gloverana, while it is narrower and more elongate in A. variana. In A. gloverana females, the sterigma is broad, with lobes connected, and a cestum is absent. In A. variana females, the sterigma is narrow with the lobes separate, and a weakly sclerotized cestum is present. In addition, females of A. variana have large abdominal scale tufts that are used to cover the eggs; these are lacking in A. gloverana females. Larval Morphology Larvae are approximately 11-15 mm in length and are bright green with a black head. The black head is lost in the final instar, where both the head and prothoracic shield are brown. An anal comb is present with 6-10 teeth. Biology Acleris variana completes one generation per year. Adults are present in August and September. The A. variana life cycle is nearly identical to that of Acleris gloverana. Females lay eggs on the underside of needles in the upper section of host trees. Eggs overwinter until the following spring, and larvae hatch starting in mid-May. First intars feed inside opening buds, mid-instars web together needles to create a nest, and last instars are free-feeding. Males and 50% of females complete 4 larval instars while the remaining females complete 5 instars. Pupation occurs in webbed needles. Adults eclose in approximately two weeks. Larval damage is similar to that of Acleris gloverana, although outbreaks of A. variana do not tend to cause tree mortality. Periods of low rainfall tend to trigger increases in A. variana populations. Host plants Acleris variana attacks primarily fir and spruce. It has been recorded from the following hosts: Family Genus/species Common name Cupressaceae Thuja plicata Donn ex D. Don western redcedar Pinaceae Abies alba Mill. silver fir Pinaceae Abies amabilis (Douglas ex Louden) Douglas ex Forbes Pacific silver fir Pinaceae Abies balsamea (L.) Mill. balsam fir Pinaceae Abies grandis (Douglas ex D. Don) Lindl. grand fir Pinaceae Abies lasiocarpa (Hook.) Nutt. subalpine fir Pinaceae Abies Mill. fir Pinaceae Larix Mill. larch Pinaceae Larix occidentalis Nutt. western larch Pinaceae Picea A. Dietr. spruce Pinaceae Picea abies (L.) Karst. Norway spruce Pinaceae Picea engelmannii Parry ex Engelm. Engelmann spruce Pinaceae Picea glauca (Moench) Voss white spruce Pinaceae Picea mariana (Mill.) Britton, Sterns & Poggenb. black spruce Pinaceae Picea pungens Engelm. blue spruce Pinaceae Picea rubens Sarg. red spruce Pinaceae Picea sitchensis (Bong.) Carriere Sitka spruce Pinaceae Pinus contorta Douglas ex Loudon lodgepole pine Pinaceae Pseudostuga Carriere Douglas-fir Pinaceae Pseudotsuga menziesii (Mirb.) Franco Douglas-fir Pinaceae Tsuga canadensis (L.) Carriere eastern hemlock Pinaceae Tsuga heterophylla (Raf.) Sarg. western hemlock Pinaceae Tsuga mertensiana (Bong.) Carriere mountain hemlock Salicaceae Populus balsamifera L. balsam poplar Distribution Acleris variana is distributed in coniferous forests from eastern Canada and the northeastern United States west to Alberta. References EPPO (European and Mediterranean Plant Protection Organization). 1997. Data sheets on quarantine pests: Acleris variana and Acleris gloverana . http://www.eppo.org/QUARANTINE/insects/Acleris_gloverana/ACLRSP_ds.pdf [accessed 7 Mar 2011]. Otvos, I. S. 1991. North American species in forestry, pp. 719-756. In L. P. S. van der Geest and H. H. Evenhius [eds.], Tortricid Pests: Their Biology, Natural Enemies, and Control. World Crop Pests, Vol. 5. Elsevier, Amsterdam. Powell, J. A. 1962. Taxonomic studies on the Acleris gloverana -variana complex, the black-headed budworms (Lepidoptera: Tortricidae). Canadian Entomologist. 94: 833-840. Powell, J. A. and P. A. Opler. 2009. Moths of western North America. University of California Press, Berkeley. 369 pp. Photo Credits Fig. 7: Rick West, Canadian Forest Service, Bugwood.org Fig. 8: Connecticut Agricultural Experiment Station Archive, Connecticut Agricultural Experiment Station, Bugwood.org Tortricids of Agricultural Importance by Todd M. Gilligan and Marc E. Epstein Interactive Keys developed in Lucid 3.5. Last updated August 2014.