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Species Hyalophora cecropia - Cecropia Moth - Hodges#7767

2nd instar cecropia larvae - Hyalophora cecropia 3rd instar caterpillar - Hyalophora cecropia Cecropia Moth - Hyalophora cecropia Robin Moth - (Cecropia Moth) - Hyalophora cecropia - female Cecropia Moth - Hyalophora cecropia - female Cecropia - Hyalophora cecropia Cecropia Moth - Hyalophora cecropia - male Cecropia Moth - Hyalophora cecropia
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 cecropia (Cecropia Moth - Hodges#7767)
Hodges Number
Other Common Names
Robin Moth
Cécropia - En français… Ilze V-G.
Synonyms and other taxonomic changes
Hyalophora cecropia (Linnaeus)
Orig. Comb: Phalaena cecropia Linnaeus, 1758
Wingspan 110-150 mm (1)
Adult: wings dark brownish, grey or charcoal-black with red shading in basal area of forewing; discal spot crescent-shaped, red with whitish center on all wings; red shading beyond PM line on all wings [this last characteristic distinguishes H. cecropia from H. columbia, which has no red shading beyond PM line]
Larva: body very large, bright green or sea green with prominent dorsal knobs: thoracic knobs orange, abdominal ones yellow; sides of body with pale blue knobs; Columbia Silkmoth (H. columbia) is very similar, but thoracic knobs red, abdominal knobs yellow-pink, knobs along sides more white than blue and set in black bases.(2)
e NA to AB (TX-FL-NS-AB) - MPG
Populations of this species can be found across most of continental North America east of the Rocky Mountains.
Cecropia moths are recorded from the Maritime Prov. of Canada (Nova Scotia & PEI) south to central Florida and west across the Eastern Plains & e. Rockies. (3)

Some reports suggest extreme ne. Mexico adj. to Texas; however, no specimens or vouchers could be located to verify the identity of reported specimens (possibly Eupackardia & Rothschildia???). Additional reports from n. Mexico are likely misidentifications of related taxa (gloveri complex).

The cecropia range overlaps that of Columbia nominate (Hyalophora columbia columbia) in the Great Lakes region of southern Canada, the Maritime Provinces of e. Canada and adjacent US states (Noting the specific habitats for each taxon usually differs), and with Glover's Silk Moth (Hyalophora columbia gloveri / syn. Hyalophora gloveri) along the eastern base of the Rockies and western Plains (Noting the differences in habitat preferences between gloveri and "western cecropia" being slight and much more congruent than that seen with columbia nominate to the east). In areas of sympatry, members of this Genus are known to readily interbreed and several blend zones between and among taxa have been identified.

Both cecropia and gloveri, and moths suggestive of cecropia x gloveri crosses, have been reported in a number of US states (incl. Texas, Oklahoma, Colorado, ne. Wyoming, w. South Dakota, w. North Dakota and e./se. Montana) and central Canada.

"H. cecropia x gloveri" ("Western fringe cecropia moths"):
Generally accepted to be "H. cecropia", some Hyalophora populations in parts of Colorado, Wyoming, S. Dakota, N. Dakota, e. Montana & central Canada often produce incredible phenotypes suggestive of "cecropia x gloveri"(?).
*However, it's important to mention some of these moths may not be "hybrids" at all, but rather represent the phenotypic extremes within the cecropia taxon proper. Nonetheless, some of these localized populations seem to be self sustaining and remain quite unique in appearance.

Colorado (cecropia x gloveri blend region)

"H. cecropia x gloveri var. nokomis":
Interesting populations can be found across central Canada where cecropia and columbia gloveri overlap. Many specimens identified as "H. gloveri ssp. nokomis" appear to possess traits typical of cecropia (i.e. red postmedial scaling and coloration).

"H. cecropia x columbia columbia":
These occasional crosses occur in the northeast (US & Canada)
For additional information on natural hybridization between cecropia & columbia in e. Canada, please refer to the following article: Bridgehouse, Derek W. A Case of Natural Hybridization Between Hyalophora cecropia and Hyalophora columbia (Lepidoptera: Saturniidae) in Nova Scotia, Northeastern Naturalist, 13(1):29-34, 2006.

P.E.I., Canada
(cecropia x columbia nominate)

Although highly variable, yet similar in overall appearance, cecropia moths do possess and exhibit some geographic variability, particularly along the fringes of the range and/or across greater distances and climate zones. Currently, the degrees of differences between & among populations is not well qualified nor quantified, so mixing populations - rearing and release - may have deleterious effects. It is well documented that localized populations often show differences in host preferences and mating times. Mixing populations by importation and release or by mixing (cross breeding) and release may cause decline in naturally evolved local populations with finely tuned ecological parameters. Please be mindful of local populations when exchanging and rearing (genetics and pathogens considered!). Nature has taken thousands of years to fine tune populations and human actions can damage that balance in a very short time!

examples of geographic variants
NOTE: Sizes and Wing Shapes!
(for details, please click on the images and refer to the comments for each pic)


Nova Scotia

sw. South Dakota & Adj. Wyoming (cecropia x gloveri blend zone ?)
Natural Habitats seem to be open areas with adjacent trees and green spaces (i.e. early successional, meadows, and waterways).
Attracted to lights and increasingly common in urban and suburban areas (1)


STATUS: "Secure"

Habitat degradation has resulted in decline of this species across parts of its range.

A. Historically more common and widespread, today the cecropia moth appears to be “UNCOMMON” or at least infrequently encountered across much of its former range.

B. Population and range decline is often attributed to the following:
1. Habitat Loss
2. Pollution
3. Herbicides & Pesticides
4. Movement and introductions of stocks from various parts of the range likely resulting in the spread of pathogens and degradation of natural gene pools. (It is often believed that introducing "new individuals/gene mixing" into a population "may boost the gene pool" by increasing genetic diversity; however, this practice may create more problems than solutions. It is never wise to corrupt populations with introductions no matter how good one's intentions.)
5. Disease & Parasites
a. Viral pathogens
b. Bacterial pathogens (Bacillus thuringiensis, BT toxins in pesticides and transgenic crops)
c. Protozoal Pathogens (Microsporidia)
d. Mycotic/Fungal Infections
e. Insect Parasites/Parasitoids
1) Hymenoptera, parasitic wasps
2) Diptera, parasitic flies
3) Possibly declining in parts of the range due to parasitism by a tachinid fly, Compsilura concinnata, introduced by the USDA to control the Gypsy Moth.

C. Currently thought to be “Globally Secure” with no conservation measures in place, populations should be monitored and conserved.

D. There is increased concern for this species as its populations decline in some areas, and it may be protected in parts of its range (This species is listed under articles of concern in a few states. It is a good idea to check with local authorities before collecting or trading).
Mostly: April-Aug (starting in Mar in the south) - MPG
Flies from March to July (3)
Caterpillar seen from May to October [cite:4627]


In the extreme southern part of the range, caterpillars may be seen as early as April (Gulf States).
Larvae feed on leaves of various trees and shrubs including alder, apple, ash, beech, birch, box-elder, cherry, dogwood, elm, gooseberry, maple, plum, poplar, white oak, willow. (3)(1) may also feed on lilac and tamarack


NOTE: After years of collecting, rearing and taking notes from others, the following list of plants have been reported &/or observed to be hosts for the larvae of H. cecropia. HOWEVER, it is very important to consider the following: A host plant consumed by the larvae of this insect in one part of the range/region may not be accepted by this species in another!

* FAVORED host plants here in the Southeast, incl. North Carolina
** ACCEPTED host plants here in the Southeast, incl. North Carolina

ACERACEAE, “Maple Family”
1) Maple (Various Taxa), Acer spp. (ACERACEAE)
2) * Red Maple, Acer rubrum (ACERACEAE) - FAVORED
3) Sugar Maple, Acer saccharum (ACERACEAE)
4) Silver Maple, Acer saccharinum (ACERACEAE)
5) * Box Elder, Acer negundo / syn. Negundo aceroides, (ACERACEAE) - FAVORED
ADOXACEAE (CAPRIFOLIACEAE), “Elderberry-Honeysuckle Family”
6) * Elderberry, Sambucus nigra / Sambucus sp. - FAVORED
7) * Sweet Gum, Liquidambar styraciflua (ALTIGINACEAE/HAMAMELIDACEAE) - FAVORED
BETULACEAE, “Alder-Birch Family”
8) * Alder, Alnus spp. (BETULACEAE) - Readily Accepted/FAVORED
9) * Birch, Betula spp. (BETULACEAE) - Readily Accepted/FAVORED
CORNACEAE, “Dogwood Family”
10) * Dogwood, Cornus spp. (CORNACEAE) - Readily Accepted/FAVORED
CUPRESSACEAE, “Cypress-Cedar Family”
11) ** Cypress, Taxodium distichum (CUPRESSACEAE) - Accepted only by FL stocks
NOTE: Cocoons have been collected from Bald Cypress in swamps with no other apparent host plants in the immediate vicinity. I have attempted to rear “Florida cecropia” on Bald Cypress with very limited success (although the larvae would eat cypress, they were prone to wander & die / larvae were allowed access to and grazed across additional offered hosts incl. buttonbush); however, for best results, it may require the collection of and subsequent experimentation with material associated with this particular host. (??)
EBENACEAE, “Persimmon Family”
12) * Persimmon, Diospyros spp. (EBENACEAE) - Readily Accepted/FAVORED
ELIAGNACEAE, “Oleaster Family”
13) Elaeagnus angustifolia L.(ELEAGNACEAE)
14) Eleagnus spp. (ELEAGNACEAE)
ERICACEAE, “Heath or Heather Family”
15) ** Azalea, Rhododendron spp. (ERICACEAE) - Accepted
16) ** Mountain Laurel, Kalmia secundiflora (ERICACEAE) – Poorly Accepted
17) * Blueberry, Vaccinium spp. (ERICACEAE) - Readily Accepted
18) Cranberry, Vaccinium spp. (ERICACEAE)
19) Bilberry & Huckleberry, Vaccinium spp. (ERICACEAE)
FAGACEAE, “Oak-Beech Family”
20) Beech, Fagus spp. (FAGACEAE)
21) White Oak, Quercus alba and related species (FAGACEAE)
22) Oaks, Quercus spp. (FAGACEAE) - ???
GROSSULARIACEAE, “Gooseberry Family”
23) Gooseberry, Ribes spp. (GROSSULARIACEAE)
24) Gooseberry, Gosularia spp. (GROSSULARIACEAE)
LAURACEAE, “Laurel Family”
25) * Sassafras, Sassafras albidum (LAURACEAE, Laurel Family) - Readily Accepted/FAVORED
MALVACEAE / TILIACEAE, “Mallow or Hibiscus Family”
26) * Basswood or Linden Tree, Tilia americana, Tilia spp. (MALVACEAE/TILIACEAE) - Readily Accepted
27) ** Hibiscus, Hibiscus spp. (MALVACEAE) - Accepted
28) ** Althea or Rose-of-Sharon, Hibiscus syriacus, syn. Althaea frutex Hort. ex Mill. (MALVACEAE) - Accepted
29) Cotton, Gossypium spp. (MALVACEAE) - ???
MORACEAE, “Fig-Mulberry Family” (??)
30) Mulberry, Morus spp, (MORACEAE, Fig Family) - ??? (in a personal communication to Troy Bartlett, Dan Mertins reports that 50 or so larvae offered this refused it and died)
MYRICACEAE, “Myrtle Family” (??)
31) * Wax Myrtle, Myrica cerifera (MYRICACEAE) - Readily Accepted/FAVORED
32) Myrtles (Various Taxa), Myrica spp. (MYRICACEAE)
OLEACEAE, “Olive Family”
33) * Fringe Tree, Chionanthus spp. (OLEACEAE) - Readily Accepted
34) * Forsythia, Forsythia spp. (OLEACEAE) - Readily Accepted
35) ** Privet, Ligustrum sinensis (OLEACEAE)
36) Lilac/Common Lilac, Syringa vulgaris (OLEACEAE)
PINACEAE, “Pine Family” (??)
Several conifer species have been reported to serve as hosts for cecropia; however, evidence suggest these reports may be misidentifications (Eacles?) and or happen stance locations where larvae spun their cocoons and are not necessarily reflective of that plant having been the larval host.
37) Tamarack, Larix laricina (PINACEAE)
38) Tamarack, Larix spp . (PINACEAE)
39) Hemlock, Tsuga spp. (PINACEAE) - ???
40) Spruce, Picea spp. (PINACEAE) - ???
41) Douglas-fir, Pseudotsuga spp. (PINACEAE) - ???
42) Fir, Abies spp. (PINACEAE) - ???
43) Pines, Pinus spp. (PINACEAE) - ???
RHAMNACEAE, “Buckthorn Family”
44) Buckthorn/Ceanothus, Ceanothus spp. (RHAMNACEAE)
45) Ceanothus, C. coeruleus (RHAMNACEAE)
ROSACEAE, “Rose Family”
46) * Wild Cherry/Black Cherry, Prunus serotina (ROSACEAE) - FAVORED
47) Pin Cherry, P. pennsylvanica (ROSACEAE)
48) Choke Cherry, P. virginiana (ROSACEAE)
49) Bitter Cherry, Prunus emarginata (ROSACEAE)
50) Various wild Prunus spp. (ROSACEAE)
51) Cherry Laurel, Prunus caroliniana - does not appear to be an acceptable host. (ROSACEAE)
52) * Wild Plumb, Prunus americana (ROSACEAE) - FAVORED
53) * Cultivated Peach, Plumb & Cherry, Prunus spp. (ROSACEAE) - Accepted
54) Wild Rose, Rosa woodsii (ROSACEAE)
55) Wild Rose, Rosa spp. (ROSACEAE)
56) Cultivated Rose, Rosa spp. (ROSACEAE)
57) * Blackberry/Brambles, Rubus spp. (ROSACEAE) - Readily Accepted
58) * Cultivated Apple, Malus sp. (ROSACEAE) - Readily Accepted
59) Cultivated Pears, Pyrus spp. (ROSACEAE, Rose Family)
60) ** Bradford Pear, Pyrus calleryana (ROSACEAE, Rose Family) – Accepted (occasionally poor!)
61) ** European Cultivated Pear, Pyrus communis (ROSACEAE, Rose Family) - Accepted (occasionally poor!)
62) Hawthorn or Thornapple, Crataegus spp. (ROSACEAE)
63) Asian Hawthorns, Rhaphiolepis spp. (ROSACEAE)
64) Antelope Bitterbrush, Purshia spp. (ROSACEAE)
RUBIACEAE, “Madder-Coffee Family”
65) * Button Bush, Cephalanthus occidentalis/Cephalanthus spp. (RUBIACEAE) – Readily Accepted
SALICACEAE, “Willow-Cottonwood Family”
66) * Black Willow, Salix nigra (SALICACEAE) – Readily Accepted
67) Sand Bar Willow, Salix interior/exigua (SALICACEAE)
68) * Willows (Various Taxa/Native & Introduced), Salix spp. (SALICACEAE) – Readily Accepted
69) Weeping Willow, Salix babylonica (SALICACEAE)
70) Poplar or Cottonwood, Populus spp. (SALICACEAE)
71) * Eastern Cottonwood, Populus deltoides (SALICACEAE) – Accepted
ULMACEAE, “Elm Family”
72) * Elm, Ulmus spp. (UMACEAE) – Readily Accepted

I have attempted to rear cecropia on many of the hosts listed above; however, based on personal experience here in the Southeast, the " * " denotes those host plant species with which I have had success. Although I was able to rear cecropia from egg to adult on many of the other plants in this list, high mortality among early instars and subsequent slow larval development was often observed. (pers. obs., Bill Reynolds)


adults do not feed
Life Cycle
Two or three generations per year in the south, one in the north.
Females call (release pheromone) from about 3 am to 4 am; the restricted hours aid reproductive isolation from other silkmoth species.(4)
2–6 eggs are laid in rows on both sides of leaf of small host tree or shrub;

eggs hatch in 10–14 days; young larvae feed in groups on leaves;

older larvae are solitary;

overwinters as a pupa in spindle-shaped silken cocoon attached lengthwise to tree branch
Tony Thomas points out: "These cocoons come in two forms,
the slim tight ones

and the loose baggy ones.

Not sure if it's sexual dimorphism with the female having the baggy cocoon.

Cocoon Morphology & Function(?):

Cocoon morphology ("baggy vs. compact") does not indicate the gender of the insect. Male to female eclosion ratios from the various cocoon types suggest cocoon morphology has little if anything to do with gender. However, cocoon morphology may have something to do with stock origins, suggesting adaptations to particular ecosystems. Regarding gender, often times the size and weight of the pupae within the cocoon can be suggestive - females usually being "weightier" by comparison (personal experience).

Observations suggest the various cocoon morphologies may have environmental purposes. In the fire-maintained ecosystems of the Southeast, the baggy cocoons are often prevalent. I have collected scorched yet viable cocoons of the baggy form in and along recent burn sites, most of which have successfully eclosed. Studies conducted on cocoon types (baggy vs. tight spindle) found that the "tight cocoon morphs" seem to possess greater protection against desiccation during cold dry winters and may be a factor for their prevalence in many areas (colder and drier ecosystems). Given the varied habitats occupied and population dynamics, there are likely several reasons we see differing cocoon morphologies in this taxon. (Notes on cocoon morphologies: pers. obs. mid-1970's thru Present, Bill Reynolds)


Multiple Generations (?):

Reported to have multiple generations in the South (??); I have NOT yet personally observed adults in nature beyond the spring/early summer months. Adults can be seen from late March thru early to mid-June across the Southeast - incl. FL, GA, AL, MS, TN, SC, and NC - however, reports of later seasonal observations may be misidentifications of related taxa.
NOTE: Callosamia spp. have two to three generations in the South and may exhibit multiple brood overlap in the extreme southern parts of their ranges.

Rearing cecropia in mesh sleeves subjected to natural outdoor conditions ("in situ") also suggests they are typically univoltine here in the South (rare exceptions may be observed). Rare incidental eclosions have been observed to occur "indoors", but are not likely the norm. Even as far south as central Florida (Ocala) cecropia pupae appear to require a series of cool spells to break diapause. (pers. obs. mid-1970's thru 2011, Bill Reynolds)

Contacts in Louisiana report two generations are possible when this species is reared in captive conditions for display and exhibit, but this observation is not likely to be typical of the local natural populations. Since stock origins are not confirmed to be local/pure and are subsequently maintained in controlled indoor conditions, their eclosion times may not be indicative of the natural/local south Louisiana populations.

Additional Observation NOTES: Rearing this species by the hundreds each year here in NC, we have occasionally seen cocoons eclose indoors during the late summer/early fall thru mid-winter suggesting that cool spells may not be required by all individuals to break diapause; however, without winter cooling, fewer cocoons eclose and we certainly see more deformations, sporadic eclosions & less synchronized emergences.

Similar observations of the occasional "off season eclosion" have also been made for Hyalophora gloveri reared and maintained indoors. (per. comm., Patrick White 2010-2012)

Hyalophora cecropia
Eastern USA, Eastern Canada, and reported from ne. Mexico (?)

There are currently no subspecies recognized; however, this taxon is subject to geographic variation and there are recognized hybrid populations containing cecropia blends.

Appears to be declining, likely due to parasitism by a tachinid fly, Compsilura concinnata, introduced to control the Gypsy Moth (2).
Not sure if this is the tachinid, but it is a tachinid and its eggs

Additional NOTES regarding the various life stages:
ECONOMIC SIGNIFICANCE (Pest, Medical significance, Venomous, … etc.)
Members of this Genus are not known to have any strong negative economic impacts on human agriculture or economy. In some instances, the larvae are considered “pesty” defoliators of fruit trees & ornamentals, however, there is no long term damage produced by the feeding habits of the larvae.

1. BENEFICIAL as an herbivore (“recycles” foliar cellulose and nutrients into frass = fertilizer)
2. BENEFICIAL as a member of the ecosystem (i.e. food chain)
3. One of North America’s most beautiful and impressive insect Genera and worth conserving!

The imposing larvae DO NOT sting; however, they do contain toxins & complex proteins in their hemolymph (blood), incl. a strong antibiotic, Attacin. When disturbed, the larvae will “bow up”, thrash from side to side and may release small droplets of hemolymph containing various toxins. This cocktail of chemicals often includes compounds derived from host foliage as well as the complex defensive proteins. In some instances, there may be severe reactions (incl. skin irritation, rash, burning & itching, watery eyes, runny nose, and sneezing - extreme reactions may include swelling and difficulty breathing). Individuals subjected to repeated or frequent exposure (usu. researchers & hobbyists) often develop allergic reactions to the cuticular hydrocarbons, body fluids, hemolymph, frass (poop & assoc. mold), and the adults’ wing scales. Prolonged exposure often increases one’s risk of sensitivity!
Print References
Covell, p. 52, plate 1--larva, 2--pupa, 10--adult (1)
Wagner, Caterpillars of Eastern North America, p. 245--photo of adult (specimen) and caterpillar (2)
Wagner, Caterpillars of Eastern Forests, p. 18 (5)
Tuskes et al., pp. 201-204 (extensive details on different instars of larva), plate 26--adult, 6--larva, figs. 39, 40--two forms of cocoon (6)
Himmelman, plate A-1, a series of photos showing life cycle (7)
Internet References
Lynn Scott's Lepidoptera Images has nice photos of an adult.
John Cody Gallery has a nice photo, some natural history info, and extensive rearing notes.
live adult and larva images plus comparison images of similar species (Moth Photographers Group)
live larva image plus description, food plants, seasonality, life cycle, US distribution map (David Wagner and Valerie Giles, Caterpillars of Eastern Forests; USGS)
Works Cited
1.Peterson Field Guides: Eastern Moths
Charles V. Covell. 1984. Houghton Mifflin Company.
2.Caterpillars of Eastern North America
David L. Wagner. 2005. Princeton University Press.
3.Moths of North America - Cecropia Silkmoth - Hyalophora cecropia
4.The Diversity of Life
Edward O. Wilson. 1992. Belknap.
5.Caterpillars of Eastern Forests
David L. Wagner, Valerie Giles, Richard C. Reardon, Michael L. McManus. 1998. U.S. Dept of Agriculture, Forest Health Technology Enterprise Team.
6.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.
7.Discovering Moths: Nighttime Jewels in Your Own Backyard
John Himmelman. 2002. Down East Books.