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1965
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Journal of the Lepidopterists' Society
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237
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DESCRIPTION AND HABITS OF LARVAE OF ANNAPHILA PSEUDOASTROLOGA (NOCTUIDAE)
William H. Evans 5130 Connecticut Avenue, Washington, D. C.
The following descriptions are based on 60 larvae reared from ova laid by three females collected during March, 1953, and March and April, 1955, in La Tuna Canyon, Verdugo Mountains, Los Angeles County, California.
Although the manuscript was completed in 1957, it seemed advisable to postpone submitting it until after Frank Sala had published information about his discovery, a few years earlier, of the habits of two closely related species of Annaphila, one of which was astrologa B. & McD. These two species fed on different plant species growing in the same area of the Santa Monica Mountains, Los Angeles County, California. In his revision of the astrologa group, Mr. Sala (1964) has clarified the status of the several species involved. The species which I reared matches the description of the newly described pseudoastrologa Sala.
In confinement, females of A. pseudoastrologa oviposited only on leaves of Phacelia minor (Harvey) Macbr., although several other species of native annual plants were also offered them.
Newly hatched larvae fed readily on leaves, flowers, and unopened buds; a few entered buds, through holes chewed in the corollas, and remained hidden inside; while others fed externally on the buds. There is no variation in the actual pigmentation of various individual larvae in the first and second instars; however, because of their translucency, some appear to be greenish and others of a purplish tint, depending on whether they have eaten leaves or blossoms. After the second molt, the larvae acquire the pattern and coloring which is maintained throughout the third, fourth, and fifth instars with only slight changes in shade and maculation. In these last three instars larvae are extremely variable, hardly any two individuals being alike.
Second Instar: Length 7 mm. Body translucent, cream-colored with fine white middorsal and subdorsal lines extending entire length. As in first, third, and fourth instars, the first two pairs of prolegs are smaller than others.
Third Instar: Length 11 mm. Pattern and coloring same as in following instar.
Fourth Instar:
Larva no. 1. Length 20 mm. Narrow white middorsal and subdorsal lines extending entire length of body, consisting of numerous minute specks of varying sizes and shapes, some confluent, others not quite touching each other; these specks never confluent for more than one-third the length of a segment. Ground color gray-green, cervical shield lighter. Thoracic segments entirely overlaid with deep purplish pink. Abdominal segments deep-purplish-pink except slightly less than one-third of the
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238
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Evans: Annaphila larvae
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Vol. 19, no. 4
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posterior and anterior portion of each segment. A broad white subspiracular line, interrupted on the central one-third of each abdominal segment by a pink area, extending from the anterior one-third of abdominal segment I to the anterior one-third of abdominal segment VIII. Ventral surface and prolegs light green. Head light green, speckled with numerous tiny gray and brown dots; setae white. Spiracles with black centers encircled with white. Prominent white thoracic and abdominal setae arise from slightly raised white tubercles with black centers.
Larva no 2. Yellow-green ground color. Area between subdorsal line and spiracles dark gray-green. A trace of pale pink surrounding each spiracle. Broad greenish-yellow subspiracular line extending from anterior of second thoracic segment to posterior of abdominal segment VIII; lower edge of line very irregular. Numerous greenish-yellow specks on bases of prolegs and on ventral surface of body. Prolegs on abdominal segment IV slightly smaller than those of segments V and VI; prolegs on segment III slightly smaller than those of segment IV.
Fifth Instar: Length 29 mm. All prolegs are same size.
Larva no. 1. Markings and coloring same as previous instar.
Larva no. 2. Ground color light green changing to brownish-green during latter part of instar; body densely speckled with small yellow-green flecks and blotches except in middorsal and suprastigmatal areas. The latter unspeckled area is 1.5 mm broad; middorsal unspeckled area is 0.5 mm wide. Thoracic segments with an indistinct middorsal line consisting of a few disconnected yellow specks. From anterior edge of first abdominal segment to rear edge of seventh abdominal segment extends a broad irregular subspiracular band of yellow-green broken into a pattern of disconnected blotches on the central one-third of each segment. Area around each spiracle tinged pink.
Larva no. 3. Ground color dark yellow-green, speckled with light yellow-green. Deep purplish-pink stigmatal stripe approximately 1 mm wide extends from first thoracic segment to rear of spiracle on abdominal segment VIII. Spiracles set on lower edge of this stripe. More purplish-pink areas at bases of legs and prolegs, and in similar locations on abdominal segments I, II, and VII. Fine middorsal line of interrupted irregular yellowish-green specks (some confluent) extending as far as the rear of abdominal segment VIII, bordered by an irregular intermittent narrow strip of gray-green. Small white tubercles from which setae arise less conspicuous, not raised quite so much, as in previous instar. Head gray-green with numerous brown and black specks.
Larva no. 4. The rear margin of each abdominal segment from number I through VI deep yellow, shading to reddish in middorsal area; these yellow bands not extending beyond upper margin of the purplish suprastigmatal line. Ground color varying from light brown with green tinge to purplish-brown (the latter shade forming a middorsal band which is almost 1 mm wide). Green subspiracular line irregular and rather obscure. Yellow-green specks on rest of body arranged similarly to those of larva No. 3.
Larva no. 5. Entire body deep purplish-pink speckled lightly with a few minute gray flecks. Broad dark yellow substigmatal line broken into a series of dashes by dark pink area on central one-third of each segment, extending from pink area on center of second thoracic segment to pink area on center of abdominal segment VII.
Larvae form cocoons on rocks, hard clods of soil, chips of wood, pieces of bark, or dead woody stems. Fragments of wood are chewed off and fastened together to form very hard thin-walled cocoons. The hollows chewed out of the wood serve as the bases of the well camouflaged cocoons. When no woody material is available, larvae attach cocoons of soil particles to clods or rocks. Pupation occurs in late May; adults emerge the following spring.
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1965
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Journal of the Lepidopterists' Society
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239
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A small series of my reared adults has been placed in the collection of
the United States National Museum. A few preserved larvae are in the
Yale University collection.
Literature Cited
Sala, F. P., 1964. The Annaphila astrologa Complex. Jour. Res. Lepid., 2 (4): 289-301 ["1963"].
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THE BEGINNING OF THE BUTTERFLY SEASON Harry K. Clench
Carnegie Museum, Pittsburgh, Pennsylvania
Work on another problem has yielded a by-product that may have some interest for collectors, particularly those who may be planning trips to areas with which they are not familiar. This by-product is a rough means of estimating the beginning of the "butterfly season" in any given place.
The estimate depends heavily on two hypotheses. The first is that the yearly course of the mean temperature in a locality can be approximated closely by a simple sine function:
R
Td = Tc + — (1- cosA)
Td = mean temperature for day d, counted from January 1; Tc = mean temperature of coldest month (usually January in the northern hemisphere); TH = mean temperature of hottest month (usually July in the northern hemisphere); R = Tn-Tc; and A =(72/73) (d-b). In the last, b is the seasonal lag and normally is around 13.5.
The second hypothesis is less well documented: that there exists a temperature threshold above which butterflies fly, below which they do not; and which also functions as a limiting value for geographical occurrence. As applied here, the threshold refers to mean temperatures and its value has been determined to be about 43° F. (6.1° C.). In confirmation of the hypothesis it can be observed that in localities where Tn is below this value, virtually no butterflies occur; and in areas where Tc is above this value, at least some butterflies fly through the winter. Furthermore, in several places where accurate data on butterflies are available the time of the year when the mean temperature, on the average, reaches this value about marks the average time of appearance of the first butterflies (overwintering hibernators).
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