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Subspecies Hyalophora euryalus kasloensis

Hyalophora kasloensis? Head 02f - Hyalophora euryalus - female Hyalophora Haylophora Cecropia Moth (Hyalophora cecropia)?? - Hyalophora euryalus - female H. kasloensis - Natural Hybrid w/ gloveric larval traits - Hyalophora euryalus - female Mystery insect in large pod - Hyalophora euryalus Mystery insect in large pod - Hyalophora euryalus Hyalophora euryalus - male
Show images of: caterpillars · adults · both
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Bombycoidea (Silkworm, Sphinx, and Royal Moths)
Family Saturniidae (Giant Silkworm and Royal Moths)
Subfamily Saturniinae (Silkmoths)
Tribe Attacini
Genus Hyalophora
Species euryalus (Ceanothus Silkmoth - Hodges#7770)
Subspecies kasloensis (Hyalophora euryalus kasloensis)
Adult "kasloensis" are similar in appearance to H. euryalus, however, the reniform crescents are typically reduced in size and length. Additionally, the coloration is often a deeper reddish-brown or wine color with a tendency for soft gray suffusion submarginally. It is important to point out that the adults of both euryalus and "kasloensis" may be subject to extreme variation in color and pattern and overlap in characteristics are not uncommon.

There is a tendency for adult moths belonging to the "kasloensis" complex to exhibit geographic variation (clinal traits) along an east to west transect. In the western part of the "kasloensis" range (= e. Washington, USA and parts of BC, Canada), aadult moths often exhibit greater euryalus traits than do adults from populations of this taxon to the north (BC, Canada) and east (w. Montana). While adult moths from the "Okanogan Valley" of e. Washington exhibit strong euryalus traits, the 5th instar larvae and cocoons often exhibit "kasloensis" characters,... suggesting past or current genetic exchange between nominate eryalus and kasloensis. Although it is not possible to say with 100% certainty where an individual "kasloensis" specimen originated, there are tendencies when one compares specimens from across the range.

1) The 4th and 5th instar larvae of H. euryalus are usu. characterized by bright yellow thoracic tubercles (scoli) with well defined black "basal collars" (ringed bases). However, some euryalus larvae may lack complete "basal collars" and more closely resemble the larvae of H. gloveri.
2) Unlike euryalus, the 4th & 5th instar larvae of kasloensis possess bright red, pink or coral colored thoracic tubercles which may or may not possess black collars at their bases. The appearance of late instar "kasloensis" larvae is much more congruent with H. columbia nominate than with euryalus.

Another difference between euryalus and kasloensis can be seen in the cocoons.
1) The cocoons of H. euryalus are typically bulbous and can be described as "evenly" tear drop-shaped with a "smooth" surface texture. The coloration of the silk may be flat gray, powdery gray, silvery, bronze, gold or a combination.
2) Although the cocoon of "kasloensis" is often shaped much like that of euryalus, it is often "tighter" and more compact in appearance. Additionally, the cocoon surface is most often streaked with silvery-bronze and may even appear coarsely textured or longitudinally striated (much like the cocoons of columbia or gloveri).
East of the Cascades and west of the Rockies (not known to be coastal) - populations are patchy across much of central and se. British Columbia, eastern Washington, n./c. Idaho (possibly western Oregon along the Idaho-Oregon border) and western Montana.
best described as forested montane/montane valleys
(forest comp. - mixed hardwood/conifer)

populations usu. occupy river basins in drier environments

Often found in cooler environments than typically seen for euryalus (esp. at night).

Climate - cool wet springs & drier mild summers
adults fly from May to July, depending on altitude, latitude, and seasonal variation

larvae in July and August
As specified under euryalus (info provided by Cotinis)

Larvae feed on a number of trees and shrubs, including Red Alder (Alnus rubra), birch, Antelope Bitterbrush (Purshia tridentata), buckthorn (Rhamnus), Buffaloberry (Sheperdia canadensis), Ceanothus species, cherry (Prunus spp.), gooseberry (Ribes), Hardhack (Spiraea douglasii), hazel, Madrone (Arbutus menziesii), manzanita (Arctostaphylos), Mountain Mahogany (Cercocarpus betuloides), Mountain Maple (Acer glabrum), rose (Rosa spp.), Saskatoon Serviceberry (Amelanchier alnifolia), willow (Salix), and conifers, esp. Douglas-fir (Pseudotsuga menziesii).
Life Cycle

1) eggs may be laid singly or in groups on or near the leaves of host plants
2) hatching occurs within 9-14 days
3) larvae feed for 6 to 8 weeks (July-August)
3) overwinters as a pupa in tough, compact, teardrop-shaped cocoon usu. attached longitudinally to twig or outer part of host plant, cocoon may be concealed by and incorporate leaves and twigs of the host plant
4) adult eclosion occurs the following spring/early summer (May-early July)
5) Mating usually occurs in the predawn hours as seen in most other Hyalophora species
The Genus Hyalophora comprises 3 species and several "anomalous populations" that have over the years been the center of controversy, incl. "kasloensis".

Currently, there are three recognized "subspecies" of euryalus and these are as follows:

Pacific coast west of the Cascades and Sierras (incl. sw. BC, Canada; Pacific coast of the USA; ranging south into Baja Mexico/Pacific coast of c. Mex.)

RARE ENDEMIC of La Isla de Cedros, Baja Calif., Mexico

A distinct "population group" of hybrid origin (euryalus X columbia group) with strong ties to the euryalus complex and currently recognized as a "subspecies" of euryalus. Isolated to a region east of the Cascades and west of the Rockies (incl. e. Washington, n. Idaho & w. Montana in the USA & sc. B.C. in Canada)


Much of the information used on this guide page was contributed by the following:
Original guide for euryalus, Contributed by Cotinis on 6 February, 2006 - 3:46am
Additional contributions by Robin McLeod, Chuck Entz, Ted Kropiewnicki, William H. Reynolds
Last updated 11 January, 2012 - 12:11pm

I would like to personally thank the following people for their contributions ... sharing specimens, images, personal observations & experiences: Dr. M. Collins, S. Smith, D. Bridghouse, Dr. J. Kruse, B. Oehlke & "shotguneddie" + many...many others for taking the time to post images & share their comments & posts.

Bill Reynolds

Genetic & morphological studies support the hypothesis that Hyalophora "kasloensis" is the product of past overlap and hybridization between H. columbia (possibly ssp. gloveri?) and H. euryalus. Collins hypothesized that "kasloensis" is best described as a self sustaining hybrid population ("columbia x euryalus" or possibly "gloveri x euryalus" ?). Breeding experiments between kasloensis & euryalus and between columbia nominate (+gloveri in part) and kasloensis revealed that among F1 progeny, there was a reduction in female fertility and sex skews (> no. of males).

Some preliminary genetic comparisons suggested the "euryalus-gloveri-columbia" group may represent a single taxon; however, recent studies indicate "kasloensis" is more closely related to euryalus than to columbia. Currently, "kasloensis" is considered a geographic variant (race) of euryalus and regarded as part of a cline within the euryalus group. Based on this premise, H. kasloensis is described as a "race"/possibly "subspecies" of the former with strong ancestral genetic influence from the columbia group.

Although "All Lep"s" lumps "kasloensis" with euryalus, I am willing to go out on a limb and acknowledge & support the notion that "kasloensis" is distinct from euryalus and deserves recognition based on the following:

1) Genetic analysis and breeding experiments support some level of taxonomic distinctiveness and recognition (supporting "Hybrid origins").
2) The presence of distinct morphological features unique to kasloensis can be seen in the adults, but are best exemplified by the larvae and cocoons.
3) The geographic range of "kasloensis" appears to be somewhat isolated from euryalus proper; the Cascades serving as a geographic barrier reducing gene flow between and among euryalus populations to the west and kasloensis to the east.
4) "Kasloensis" populations are reproductively stable.
5) Many Lep enthusiasts and specialists still preferentially refer to this taxon as "Hyalophora kasloensis" and would like to see it recognized as distinct based on observed differences.
6) Due to the above, moths known as "kasloensis" still fuel persistent debates among specialists (and taxonomic placement remains unresolved for many)

Hopefully the taxonomic ambiguities will be resolved in the near future.
See Also

Pacific coast west of the Cascades and Sierras (incl. sw. BC, Canada; Pacific coast of the USA; ranging south into Baja Mexico/Pacific coast of c. Mex.

NOTE: Hyalophora gloveri ("Sonoran & Mexican variants") may be similar in color & pattern to euryalus and kasloensis.

*Compare additional images of euryalus & gloveri.
Observation: Regarding this link, 1st image identified as "euryalus" in this series (2nd to last pic) is suspect. All pattern forms, color forms and geographic variations of "euryalus" considered, this particular specimen is inconsistent with "euryalus" and is more typical of a "cecropia blend" in characteristics. No additional collection/rearing data regarding location/origin for this specimen was available (??).

Cecropia Moth, Hyalophora cecropia, has more gray in the basal half of the wings, the reddish band beyond the PM line is narrow and sharply defined (not broad and diffuse), and the discal spots on its hindwing are not elongated.

*Compare additional images of euryalus and cecropia. (NOTE: Middle image identified as euryalus is suspect...??)

VARIABLE - refer to the following list of taxa:

Additional Info.
Print References
The Wild Silk Moths of North America: A Natural History of the Saturniidae of the United States and Canada
By Paul M. Tuskes, James P. Tuttle, Michael M. Collins

Internet References
Works Cited
1.The Wild Silk Moths of North America: A Natural History of the Saturniidae of the United States and Canada
Paul M. Tuskes, James P. Tuttle, Michael M. Collins. 1996. Cornell University Press.