Exyra fax Grt (may be same as E. rolandiana Grt.)

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Food Plants (E. fax and E. rolandiana)

Sarracenia purpurea; found only once in S. psittacina.

Distribution (E. rolandiana, unless noted) (See Map)

• FMJ
• Maine—Katahdin Iron Works.
• New Jersey—Tom's River, Absecon, Lakewood, Whitings, Tuckerton
• Pennsylvania—Pocono
• Delaware—Rehoboth, Bethel, Concord, all Sussex Co.
• North Carolina—Southern Pines, Hamlet
• Alabama—Bay Minette, Theodore
• Mississippi—Wiggins
• Smith: Massachusetts; Eastern, Middle, and Central States; Fax, Southern States
• Dyar: Atlantic States. Fax, Southern States
• Fletcher: Ottawa
• Gibson: Ontario
• Fiske: New Hampshire
• Grote (fax): Georgia

Description

Egg—Dome shaped, not so high as in the egg of semicrocea; diameter, 0.54mm; height, 0.38mm; vertical ribs slightly more numerous (about forty to fifty) than in semicrocea, much less deeply cut, and with the cross striations very faint; pale dull yellow, with a pearly luster. Usually deposited in groups of four or five to fifteen or more, on the inner walls of the pitchers of Sarracenia purpurea Linn.

Larva

Stage I—Translucent amber brown, segments A1, 2, 3, and 4 denser, more reddish; surface polished; head, cervical shield, and tubercles wood brown, the latter tipped with black; width of head, 0.32mm; tubercles, in structure size, and arrangement as in semicrocea; total length at hatching, 2.3mm.

Stage II—Color denser by greater pigmentation, the pale dorsal line more obvious. Width of head, 0.44mm; faint indications of the head pattern are sometimes visible; eyes and surrounding area black. In this instar, while the setal arrangement remains identical with that of semicrocea and ridingsii, the characteristic enlargement of certain setae, foreshadowing the "lappets" in those species, does not take place; the larger tubercles become microscopically spinose at their apices, but kappa, on segments A1, 2, 3, and 4, is not proportionately larger than in the first instar; at 100x, a fine short sparse pubescence, generally distributed is visible.

Stage III—Some examples pale dull amber brown, others decidedly brighter and redder in hue; pubescence more marked, but still microscopic. Width of head, 0.67mm; head pattern in some examples very faint, in others strongly developed. This stage is also marked by some increase in the size of the tubercles, without, however, even approximating the "lappet" condition of the other species; the segments are deeply cut, and the larger tubercles, alpha, beta, kappa, especially on the first four abdominal segments, are more prominent by surmounting broad swollen areas on these segments as in the other species, the larger tubercles are microscopically sparsely bristled, more strongly at their apices, as well as bearing their usual single strong seta.

Stage IV—Color as before. Head width, 0.9 to1.0mm; color pattern of head strongly developed, pale and dark brown, contrasting. More generally and strongly pubescent than in the previous instar; the tubercles almost submerged in the bristly pubescence which surrounds them; broadly constricted white, contrasting, intersegmentally.

Stage V, last larval instar—Sometimes rather dull brown, usually bright purplish red, though rarely as brilliant in tone as the more highly colored examples of semicrocea; always contrasting with the broadly constricted intersegmental white areas, which in all the species are destitute of pubescence. Width of head, 1.35 to 1.5mm; head pattern essentially as in the other two species, but the dark bands are usually broader and tend to coalesce, proportionately narrowing the pale areas Pubescence stronger and more abundant, almost concealing the tubercles, especially on the dorsal segments of A1, 2, 3, and 4, where the abundant dark bristly pubescence faintly reproduces the saddle-shaped marking of semicrocea of like age; tubercles small, except for the absence of "lappet" development arranged as in semicrocea and ridingsii. Total length before pupation, about 25 mm.

Pupa

Length, excluding caudal setae, 12 mm. Pupal cuticle not heavily chitinized, thin, flexible; paler examples sufficiently transparent to exhibit the color-pattern of the imago; color varying from pale amber to dark brown.

Front not strongly produced over head; Prothorax of moderate length; epicranial suture present; labial palpi indicated by a slit-like separation of the maxillae, narrowly in contact with the labrum. Mesothoracic wings extending to the incision between the fourth and fifth abdominal segments; metathoracic wings visible dorsally to the fourth abdominal spiracle; maxillae and mesothoracic legs of about equal length (maxillae slightly the longer), extending almost to the caudal margin of the wings; antennae shorter, terminating about opposite the incision between the third and fourth abdominal segments; mesothoracic legs do not reach cephalad to the eye-pieces; prothoracic tibiae narrowly visible.

Dorsal cephalic margin of abdominal segment five striated; dorsal caudal margin of segment four punctate. Caudal end of body with two long straight setae and a few shorter, slightly hooked setae; all other setae fine, pale, very inconspicuous.

Imago

Male expands 20 to 24mm; average, 23mm; colors, yellow and purplish red or claret red.

Female expands 17 to 21mm; average, 19mm; colors deeper and duller red than the male, with little or no yellow; extreme forms have all deep purplish black, almost unmarked wings. (fax Grt.?)

Head and Thorax

Densely hairy, bright orange red, deeper in the female; antennae pale yellowish brown to almost black in the dark forms; length of antennae about 6mm; of tongue, 5mm; palpi densely hairy, varying from dull red to black.

Legs

Shorter and proportionately stronger than in the other species; dull brown, fore and middle tibiae dark brown, brownish red, or even bright claret red; in the dark female, black.

Wings

Shorter and broader than in the other species, especially those of the female. The primaries of the male are usually bright claret red to deep purplish red, with somewhat obscure markings of deeper tone, and with more or less clear bright yellow medially, the colors and markings usually distributed as follows: from the base to the transverse anterior line, red or purplish red; the basal line not evident; the transverse anterior line is usually traceable as a narrow darker margin to the basal red area, and is variable in course, though usually arched from the costa to below the cubitus, thence bent outwardly to the inner margin; beyond the transverve anterior line there is usually an irregular yellow blotch-like marking which may extend along the inner margin and enclose the base of the transverse posterior line, being faintly divided by a fading out median shade; it may extend forward between the transverve anterior and median lines, beyond the middle of the wing, its continuance thence to the costa sometimes being indicated by a lightening of the red ground; or the yellow area may be greatly restricted or disappear, its last trace usually being an irregularly rounded spot over the cell, within the median shade; the lower half of the median line may be faint or well marked, but the upper half is usually broad, expanding as a dark shadow which edges internally a yellow or pale red reniform, obscurely lunate, beyond which the band merges into the red of the costa; except for the reniform and the variable yellow area along the interior margin, the wing outwardly from the median line is red, a narrow transverse posterior line showing darker on this ground, and a more diffuse subterminal line is sometimes similarly visible; the fringes are concolorous with the terminal area of the wing.

In the darker males, especially those from the Southern States, these markings may be greatly obscured, the clear yellow and bright claret red dulled with gray, the transverse lines darkened, and the whole aspect of the insect changed; but full intergrades seem to exist, and the structural characters are unmodified in both the larvae and the adults; the secondaries of the male vary from pale gray with a faint median line and darker border, to almost uniform dark smoky gray.

The females are shorter winged and more robust than the males; their primaries are usually of a deeper purplish red than in the males, on which the yellow areas may appear as lighter brighter red, or if yellow is present, reduced to a rounded blotch within the median line, and to the reniform; the dark dull purplish tone is more or less overlaid especially basally, with scattered orange red scales, and the markings generally are more diffuse and obscure than in the male. Southern examples are usually smaller and darker than the northern ones, in extreme examples both pairs of wings becoming almost uniformly deep purplish black, the primaries marked almost microscopically with a few scattered red scales. (fax Grote?)

Beneath the wings of both sexes vary from dull smoky yellow to deep black, the pale males sometimes showing some purplish red suffusion, and having the primaries darker than the secondaries.

Abdomen

Extending well beyond the secondaries; usually concolorous with the secondaries, that of the male with a terminal tuft of orange red hairs, though in the darker duller forms this is obscured.

Male genitalia

Similar to semicrocea, but with the saccus shorter and narrowing to a rounded point.

NOTE: Grote's types of fax were from Georgia; Smith's record of Delaware for fax grew out of a misapprehension; the single specimen upon which this record was based came from North Carolina, and being one of the small dark females described above; there seems little doubt but that the names fax Grote and rolandiana Grote apply tone variable species, fax having preference, and rolandiana properly being restricted to the brighter paler northern form.

Images

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• Exyra eggs and pupae
• Exyra larvae
• Exyra pupae
• Exyra moths

Bibliography

E. rolandiana

• 1877. Grote . Psyche, II, 38.
• 1877. Thaxter , Psyche, II, 39, iv .
• 1882. Grote . Ill. Essay, 64. il .
• 1891. Smith. List Lep . Bor. Am., 56.
• 1893. Smith. Cat. Lep . Sup. Noct ., 306
• 1894. Fletcher. Rpt. Ent . Soc. Ont., XXV, 44-46.
• 1899. Fiske . Ent . News, X, 294.
• 1901. Givson . Rpt. Ent . Soc. ONt . XXXII, 111.
• 1902. Dyar . List N.A. Lep ., 211.
• 1903. Smith. Check List Lep . Bor. Am., 51.
• 1904. Jones. Ent . News, XV, 14-17, il .
• 1907. Jones. Ent . News. XVIII, 413-414.
• 1908. Macfarlane. Das Pflanzenreich , IV, 110, 17-18.
• 1917. Bar. & McD , Check List Lep . Bor. Am., 75
• 1921. Jones. Natural History, 21: 296-316. 22 ill.
• 1942. Lloyd. The Carnivorous Plants. Pgs. 36-37.

E. fax

• 1873. Grote . Trans. Am. Ent . Soc., IV, 295 ( Xanthop.)
• 1874. Grote . Bull. Buff. Soc. Nat. Sci ., II, 36.
• 1879. Grote . Can. Ent ., XI, 236.
• 1891. Smith. List Lep . Bor. Am., 56.
• 1893. Smith. Cat. Lep . Sup. Noct ., 306
• 1902. Dyar . List N.A. Lep ., 211.
• 1903. Smith. Check List Lep . Bor. Am., 51.
• 1904. Jones. Ent . News, XV, 14-17, il .
• 1917. Bar. & McD , Check List Lep . Bor. Am., 75 

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