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Journal of The Lepidopterists' Society

Volume 28                                     1974                                      Number 2

NOTES ON THE LIFE CYCLE AND NATURAL HISTORY

OF BUTTERFLIES OF EL SALVADOR. III. ANAEA

(CONSUL) FABIUS (NYMPHALIDAE)

Alberto Muyshondt 101 Avenida Norte #322, San Salvador, El Salvador

This is the third article in a series dealing with what my sons and I liiive found related to the life cycle and natural history of Rhopalocera encountered in the vicinity of San Salvador, capital city of El Salvador. lAs stated in our previous articles, the purpose of the series is to present I he life cycle, including observations on the behavior of the early stages nnd adults, and to make known the foodplant of the local species of Neotropical Rhopalocera, as according to the literature many of them lire incompletely known, and have been classified solely on the adult morphological characteristics. A major difficulty has been the identification of the species described. To overcome it, we have requested the help of Museums, mostly the Allyn Museum of Entomology, where Dr. I i. D. Miller has made the identifications.

This particular species has been placed through time in various genera by different authors: Cramer (1775) in Papilio, Hiibner (1807) in Consul, and Protogonius (1819), Duncan (1837) in Fabius, and Double-day (1844) in Helicodes. A host of specific names has been used too, among them the best known is hippona used by Fabricius (1777). We follow the name used by Comstock (1961), Anaea (Consul) fabius Cramer. Comstock leaves open the possibility that some subspecies might be valid.

In our first article (Muyshondt 1973a) a summary description of the country and its climatic conditions was made. A. (C.) fabius is a dweller of wooded land, preferring ravines or creeks that cross coffee plantations (that are man made forests in this country). We have found the species from sea level to about 1500 m. In October 1969 we saw for the first time a female ovipositing on a plant that was identified as a Piperaceae, near

82                                                Journal of the Lepidopterists' Socm-;*™

Izalco, a town located about 45 km. W of San Salvador. In Octol« 1970, larvae in different stadia were found and collected near the villim of Zaragoza (some 15 km. SSW of San Salvador), this time on hvi different species of the same Piperaceae. A few days later, in the sa-Zaragoza area, another female was observed ovipositing and eggs \vi« collected, put in individual transparent plastic bags and brought bud to our laboratory. Photographs were made of the eggs and the subs* quent stages of development until the adults emerged. Records of Ilia developmental time, size and mortality were kept, and specimens of Ilia different stadia were kept in alcohol. Since then the species has bcfl reared during various months of the year to establish seasonal variatioiw Several species of Piperaceae, in addition to the ones on which the vyM and larvae were found, have been successfully used as foodplants. BnvtM ing in all instances has been carried out under ambient lighting aufl temperature conditions. No moisture control was kept, but it was usualljB very high due to the fact that the material was kept in plastic ba even though these were cleaned every day.

Life Cycle Stages

Egg. Translucent white with greenish tinge, almost spherical, with flattened h ■ and depressed micropyle, surface smooth, and about 1 mm in diameter; all hah I,. in 5 days.

First instar larva. Head light brown with darker markings, roundish, dispiij portionately large in relation to body, that is wedge-shaped from head to caudal cnttfl grayish brown with scarce fine pilosity. After feeding on the leaf changes color l(fl greenish-brown with tiny yellow markings. Measures upon emerging about 2 mif| and grows to about 4.4 mm before moulting in five days.

Second instar larva. Head black with tiny tubercles, white and yellowish, scattered mostly alongside lateral borders of epicrania. Two stubby horns on ape* of epicrania. Body dark brown (almost black) with lighter peppering, thickeiiiir from first thoracic segment to first abdominal segment, tapering then gradually (1 10th abdominal segment. Grows to 0.9-1 cm in six days.

Third instar larva. Head black with prominent tubercles, white or yellow, scattered in the area between ocelli and epicranial horns, which are now thickeifl slightly longer and terminated in several short spines bearing thin setae. Bod* dark brown to black with heavy yellow sprinkling mostly on thoracic and niiib abdominal segments. On the caudal portion of the abdomen, sprinkling concentra(n|| along spiracular area. Larvae grow to 1.5-1.8 cm in 4-5 days.

Fourth instar larva. Head black with parallel vertical yellowish lines starting ill adfrontal zone, the last and smallest located behind the ocelli. Head as thick ui thickest abdominal segment. Body very dark brown or black with white sprinklin^l mostly concentrated on thoracic segments. Inconspicuous warts with tiny spini'Ki placed one at each side on subdorsal area of third thoracic segment. Scarce l>u noticeable setae alongside subspiracular area. White sprinkling on fourth abdomimtl segment and spiracular zone of caudal abdominal segments. Tubercles on head ven abundant, most prominent of them yellow. Stubby horns with many tubercles and thick short spines with setae. Grows to 2.4-2.6 cm in 4-5 days.

Fifth instar larva. Head black with some black and many yellow tubercles nm«.| prominent at sides of epicranium, and two near the upper adfrontal area. From

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yellow, then yellow parallel vertical bands low on the epicranium. Horns as in fourth instar, but thicker and slightly longer. Body now dark green with dark red stains dorsally, mostly on thoracic segments and last abdominal segments. Spiracula yellow, surrounded by greenish ring. Spiracula on 2nd abdominal segment placed higher than the rest, same as spiracula on eighth abdominal segment. White peppering scattered on body mostly on thoracic segments. Body now thicker than head, and short in relation to thickness. Grows to 3.5-3.8 cm in 9 or 11 days.

Prepupa. Very thick and incurvated laterally, body all green. Duration two days.

Pupa. Generally light green, occasionally light brown. Cremaster shining black. Abdominal segments taper sharply from wingcases (the thicker part of the pupa) to cremaster; thoracic segments taper gradually to slightly bifid head. Measures 1.6-1.9 cm long, 1.2-1.3 cm laterally at widest point, and 1-1.1 cm dorsoventrally at thickest point. Duration 10-11 days.

Adult. Shape of wings unique in genus. Forewing with projected angle starting at apex, going outwards to vein M 2, then sharply inwards to vein M 3, then slightly convex to tornus. Color dorsally dull black with conspicuous elongated yellow spot apically and row of three yellow elongated spots going from mid-costal area towards mid-outer margin, with an oval one under the last. Orange band covering basal and discal areas, parallel to black inner margin, not reaching tornus. Hindwing rounded with more or less spatulate tail on vein M 3, and sharp anal angle. Color orange except for dull black border alongside outer margin, with row of 4 yellow spots in black area, between tail and anal angle. The underside of both fore and hindwings is grayish-brown of varying shades, with no definite pattern. The body is orange, eyes reddish, antennae black basally, then orange turning to yellow, the tip usually black.

No striking differences exist between the sexes, males somewhat smaller than females and having orange hairs alongside inner margin of hindwings. Much variation in shape of projected angle of forewing and of tails on hindwing, even among individuals emerged during same month. Total developmental time for this species varies from 45 to 50 days, females usually taking more time than males.

Natural History

All the plants on which we have found eggs and larvae of Anaea (Consul) fabius, and all the plants we have used as substitute food for the larvae, belong to the Piperaceae family. We have collected eggs and larvae on Piper tuberculatum, Jacquin, P. auritum H.B.K., and P. umbellatum L. and have used some others, not determined, with success when unable to obtain the original foodplant. Piperaceae in general are very common all over the country, among heavy second-growth plant communities, in humid ravines, along creek beds and coffee plantation roads. All the foodplants we have used have aromatic properties due to the content of essential oils, and usually have bitter flavor,

The recently emerged larvae of A. (C.) fabius eat the egg shell completely and stay under the leaf without further feeding for one day. Then the larvae move to the border of the leaf, usually to the tip, select a terminal of a vein, eat around it and prolong the vein with frass stuck with silk. The larvae use this as a perch when not feeding, and usually keep the head pointing outwards. This characteristic behavior is kept through the first, second and third instars. It sometimes happens that

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Figs. 1-9. Anaea (Consul) fabius Cramer: (1) egg, about 1 mm; (2) first instar larva recently hatched, about 2 mm; (3) first instar larva 4 days later, about 4 mm; (4) second instar larva, about 1 cm; (5) third instar larva, about 1.7 cm; (6) fourth instar larva, about 2.4 cm; (7) fifth instar larva, two days after moulting, about 3.6 cm; (8) head of fifth instar larva; (9) prepupa, showing peculiar attitude.

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Figs. 10-14. Anaea (Consul) fabius Cramer: (10) side view of pupa, about 1.7 cm long, 1 cm dorso-ventrally; (11) ventral view of pupa; (12) dorsal view of pupa; (13) adult, dorsal view, about 6.3 cm; (14) adult, ventral view.

the whole leaf is eaten during this period, in which case the larvae move to another leaf where they make a new perch using the same system. During the fourth instar the larvae wander about the plant for two or three days, choose a larger leaf, and roll a portion of it, using silk, in the shape of a long funnel. From then on, until pupation, they remain

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inside of this funnel while not feeding, the head blocking the wide end and expelling the excreta through the narrow end. After feeding, usually done at dusk, the larvae come back to their hiding place, put the caudal end in position and crawl backwards into the funnel. When ready to pupate, the larvae abandon their funnel, wander about the shrub until they find a suitable place (a twig or a leaf, not always in the same plant, but always among heavy foliage), weave a small pad of silk, affix thereon the anal prolegs and stay there with the body incurvated laterally, not hanging. Just before doing this, the larvae expel an amount of greenish liquid mixed with excreta. The larvae of A. (C.) fabius through all instars are very slow moving, and when touched with a thin object make pushing movements with the tubercled head, and emit a pungent, though not disagreeable, scent, apparently from an eversible gland located anterior to the front thoracic legs.

The pupae are either light green or light brown, regardless of environmental conditions, at least under laboratory conditions. We have simultaneously had green and brown pupae from larvae raised on similar diets, and among green leaves. The pupae are rather stiff and generally do not react when handled. At most, the pupae effect a short lateral swing.

The adults of A. (C.) fabius are, with the adults of A. (C.) electra West-wood, the slowest of all the Charaxinae found in El Salvador, even if, compared with other butterflies, they are rather fast. Males are very aggressive, and exhibit strong territorial defense behavior. They sit on top of a leaf, or at the side of a tree trunk, wings flapping from time to time, and will dash at anything flying near their resting place, whether it is another butterfly or just a falling leaf, then will return to the same or a nearby perch. Both sexes are very fond of feeding on fermenting fruits, sap of trees and even animal excrements. We have never seen them at flowers.

When the females are ready to oviposit, they fly rapidly to the area where the foodplants are located, fly around one of the plants several times, and then approach the chosen one rather hesitantly, alight under a leaf, usually of medium development, and deposit one egg on the undersurface of it. They usually repeat the action on the same plant or on a neighboring one several times before flying away.

Many times, when breeding this species, we have had tachinid larvae kill the larvae of the butterfly, generally when they reach the fifth instar or shortly after pupation. Some specimens of the adult of the tachinid have been sent to the U.S. Department of Agriculture for determination and these have been identified by Dr. C. W. Sabrosky as Chrysotachina sp. Another parasite found, even if very seldom,

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is a Chalcididae, determined by Dr. B. D. Burks, of the U.S. National Museum, as Spilochalcis sp., probably a new species. This latter parasite is polyembrionic and practically fills the pupa shell. In the case we sent for determination, 55 adults of the parasite emerged from one pupa. Apparently more than one egg had been injected, as males and females of the parasite were found.

The larvae of A. (C.) fabius are very prone to a disease that softens their body until they burst and die. We have not witnessed any case of predation.

Discussion

According to Comstock (1961), the life cycle of Anaea (Consul) fabius has been at least partially described by several authors: Stoll (1787), Sepp (1852) (both under the name Papilio fabius), and Miiller (1886) (under the name Protogonius drurii). Amazingly, Sepp mentions Mespilus americana (sic) as the foodplant. The genus Mespilus has been replaced, according to Standley (1922), by the genus Crataegus L. and belongs to the Malaceae (Apple family). In El Salvador at least, this species, Anaea (C.) fabius, feeds exclusively on Piperaceae. Was this a case of misidentification, or was a wandering pre-pupal larva or a pupa found in a nearby Mespilus?

Apparently this is the first time a complete description of the life cycle of this species has been made, with photographs of the different stages as was the case with the descriptions of the life cycles of the other two Charaxinae, Prepona omphale octavia Friihstorfer and Anaea (Zaretis) itys Cramer (Muyshondt, 1973a, b).

The egg of A. (C.) fabius is exactly like the egg of A. (C.) electra Westwood (with whom it shares the foodplant), Anaea (Memphis) eurypyle confusa Hall, A. (M.) pithyusa R. Felder and A. (Z.) itys (this last one is yellowish instead of greenish). The larvae are very much like the larvae of A. (C.) electra, even in coloration, and it is very hard to tell them apart until the fifth stadium, when the color of the head is lighter in A. (C.) electra. The larvae of A. (M.) e. confusa and A. (M.) pithyusa have the same shape as A. (C.) fabius but a completely different coloration. The larval behavior of the whole group of Anaea spp. mentioned, with the exception of A. (Z.) itys, is very similar in all ins tars from one to the other; they make the perch with the bared vein during the first stadium, and the funnel-shaped refuge during the fourth instar. During the pre-pupal stage all Anaea spp. we have reared behave alike: they do not hang like most Rhopalecera, but stay incurvated laterally, the body in contact with the supporting object.

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The species A. (C.) fabius exhibits a very effective defense mechanism based primarily on crypsis during the early stages: the translucent small egg is very hard to spot on the shadowy under-surface of the leaf; then the first, second and third instar larvae spend most of their time perched on the prolonged vein of a leaf, resembling to perfection a dried portion of it. The fourth and fifth stadia are spent hiding within the funnel-like contraption they make with their chosen leaf, and its entrance is blocked by their massive and tubercled head. The color and relative smallness of the pupae make it hard to locate among the profuse foliage of the shrubs. This cryptic behavior is common to most Anaea spp. found in this country, with the exception of A. (Z.) itys. But even this one, as well as the other Charaxinae we have studied, Prepona omphale octavia, behaves in the same manner up to the third instar.

The adult of A. (C.) fabius, while in flight, can very easily be mistaken for a faster flying Licorea sp., Tithorea sp. or even an Heliconius telchinia Doubleday, all of which belong to families classically considered unpalatable: Danaidae, Ithomiidae and Heliconiidae. This group is supposed to form a Miillerian mimicry complex. It is our opinion that A. (C.) fabius, feeding exclusively on Piperaceae, plants well-known for their content of essential oils and other at least bitter compounds, could very well have developed protective unpalatable characteristics, which augment its imitative coloration, and so effect its Miillerian mimicry in this complex. This would explain the slowness of A. (C.) fabius in comparison with the other swift flying Anaea spp. But A. (C.) fabius adults do not solely rely on this defense mechanism: they also have the cryptic coloration of the underwings which makes the individuals inconspicuous among dry leaves. The species seems to enjoy a dual defense: unpalatability plus crypsis.

It is to be noted that this duality of defense mechanisms seems to exist even during the larval stage. In addition to the cryptic behavior described above, the larvae, when molested, extrude a gland located anterior to the prothoracic legs and emit a pungent scent.

In spite of the complicated defense mechanisms of A. (C.) fabius, and the dusk and dawn feeding habits of the larvae, that minimize the risk of day-feeding predators, the mortality imposed on the species by ingestion-parasites is considerable. These ingestion-parasites are the Tachinidae that deposit their eggs on the leaf where the larvae are feeding. Regardless of the short developmental period (less than two months), which would allow no less than six generations a year, this species is rather scarce in the country, and mostly so during the rainy season. This fact leads us to deduce that parasites (Tachinidae in particular), are the principal factor that keeps the species in check.

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Parasites, being in general small animals, are, according to Janzen & Schoener (1968), much affected by dryness, such as is the case in El Salvador from November to April. Thus it is during these months that A. (C.) fabius should be less affected by them and therefore should be more abundant. That is exactly what happens in fact.

Acknowledgments

We are deeply grateful to Stephen R. Steinhouser for giving us access to his technical library and for sharing with us his own observations on adults of this species. To Dr. Lee D. Miller of The Allyn Museum of Entomology, who identified the species for us, and Dr. Theodore D. Sargent, who revised the manuscript, we express our gratitude. The eldest of this group is very thankful for the help and cooperation of his five boys, without which this study would not have been possible. We also thank Drs. B. D. Burks and C. W. Sabrosky for identification of the parasites mentioned. Specimens of early stages and adults have been deposited in The Allyn Museum of Entomology, Sarasota, Florida.

Literature Cited

Comstock, W. P. 1961. Butterflies of the American Tropics, the genus Anaea

(Lepidoptera-Nymphalidae). Amer. Mus. Nat. Hist., New York. p. 51, 173. Cramer, P. 1775. Papillons exotiques des trois parties du monde: L'Asie,

L'Afrique et L'Amerique. Amsterdam. Vol. 1. p. 141, 152. Doubleday, E. 1844. List of Lepidopterous Insects in the Collection of the

British Museum. London, Vol. 1. p. 112. Duncan, J. 1837. Foreign Butterflies. Nat. Library, Edinburgh. Vol. 18. p. 167. Fabricius, J. C. 1777. Genera insectorum, etc. Chilonii. p. 265. Hubner, J. 1807. Sammlung exotischer Schmetterlinge. Augsburg, p. 148.

----------. 1819. Verzeichniss bekannter Schmetterlinge. Augsburg, p. 100.

Janzen, D. H. & T. W. Schoener. 1968. Differences in insect abundance and

diversity between wetter and drier sites during a tropical dry season. Ecology

49: 96-100. Muller, W. 1886. Zool. Jahrb. Zeitschr. Syst. Geogr. Biologia der Tiere. Jena.

Vol. 1. p. 503. Muyshondt, A. 1973a. Notes on the life cycle and natural history of butterflies

of El Salvador. I. Prepona omphale octavia (Nymphalidae). J. Lepid. Soc.

27: 210-219. ----------. 1973b. Notes on the life cycle and natural history of butterflies of El

Salvador. II. Anaea (Zaretis) itys (Nymphalidae). J. Lepid. Soc. 27: 294-302. T Sepp, J. 1852. Surinaamische Vlinders, Amsterdam. Vol. 3. p. 283. Standley, P. C. 1922. Trees and Shrubs of Mexico (Fagaceae-Fabaceae). Cont. ,

U.S. Nat. Herb, Vol. 23(2). Stoll, C. 1787. Supplement, Papillons exotiques des trois parties du monde.

Amsterdam, p. 9.

I

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THE REARING OF THE NEOTROPICAL BUTTERFLY MORPHO PELEIDES (NYMPHALIDAE) ON PEANUTS

Allen M. Young

Department of Biology, Lawrence University, Appleton, Wisconsin 54911

This paper summarizes a rearing study of Morpho peleides Kollar (Fig. 1, as form limpida Butler) on the leaves of peanut, Arachis hypogaea L. (Leguminosae) under laboratory conditions in Costa Rica and Appleton, Wisconsin. It is generally known that the caterpillars of several South American species of Morpho feed on a variety of leguminous vines, shrubs, and trees (d'Aranjo e Silva et al., 1968). A recent study of the life history of Morpho peleides in Costa Rica and El Salvador reports several papilionaceous legumes as foodplants of caterpillars (Young & Muyshondt, 1973). But there are no records of this butterfly feeding on peanut, which has a very widespread geographical distribution in the New World tropics (Leon, 1968).

This study was undertaken primarily for the purpose of developing reliable and relatively easy methods for culturing the butterfly, as a prerequisite to experimental studies on the biochemical and behavioral aspects of feeding in Morpho caterpillars. The choice of Morpho peleides was made since mated females are very easy to obtain in the wild, and also because it is a member of the very frequently encountered achilles complex (or super species) in all of tropical America.

Methods

The object of this study was to rear individuals from the egg through the adult stage. Eggs were obtained by confining a single healthy female butterfly in a 25 X 37 cm clear plastic bag containing a piece of fresh foodplant (usually Mucuna urens was used for this purpose). By repeating this procedure with several different females, a large number of viable eggs were obtained. Eggs were harvested from the leaves each day and the foodplant cuttings were replaced as they dried up. Females were removed from the bags and fed once or twice daily on juices from rotting banana. On the average, a mated female about 3-5 days old when caught lives three to four weeks in this manner and lays between 10 and 105 eggs (an average of 65 eggs, N = 28 females) during this period. Eggs were subsequently transferred to smaller plastic bags for hatching, keeping them at densities of usually 15 to 20 eggs. Eggs from each female were raised separately. All females used in this study as sources of eggs were wild caught at two mountain localities (1000 m. elev.) in the central

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Fig. 1. Morpho peleides limpida Butler from Cuesta Angel, Heredia Province, Costa Rica: female (above), and male (below). About one-half natural size.

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Table 1. Developmental time (days) and some related ecological statistics for Morpho peleides on natural (Mucuna urens) and novel (Arachis hypogaea) food-plants in the laboratory.*

* The data are pooled here for measurements taken in San Jose, Costa Rica and Appleton, Wisconsin since results were very similar in both places. The raw data from each of these localities are, however, available upon request. The measurements of ecological statistics were always made on both foodplants simultaneously, so that all individuals were always exposed to the same environmental conditions (see text for a description of laboratory conditions).

** See also Young & Muyshondt (1973) for other estimates of egg-adult developmental time and size range in Morpho peleides.

highlands of Costa Rica (Cuesta Angel on the Caribbean slopes of the Central Cordillera, and Bajo la Hondura on the Pacific slopes). The butterfly is unusually abundant at both places, and females were easily baited with rotten fruit.

A pilot rearing study was performed at Lawrence with a few eggs of M. peleides hyacinthus and M. polyphemus sent from El Salvador by Alberto Muyshondt. These eggs were reared on peanut under green house conditions. The caterpillars, in second instar, were then transported to Costa Rica and rearing continued on peanuts obtained locally. The success of this pilot study prompted the initiation of a larger scale rearing of peleides caterpillars simultaneously on Mucuna urens, a natural foodplant (control), and peanuts, a presumably novel foodplant for this species. This study was conducted in two parts: the first experiment was run in San Jose, Costa Rica, and the second one later in Appleton, Wisconsin (Lawrence University).

A total of 300 eggs was used for the Costa Rican study. These were

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Fig. 2. Thriving laboratory cultures of Morpho peleides and M. polyphenols on peanuts at Lawrence University: (A) M. peleides—fourth instar; (B) M. peleides —fifth instar; (C) M. polyphemus—fourth instar; and (D) an adult peanut (Arachis hypogaea) plant (about % m tall) bearing two fourth instar Morpho caterpillars.

obtained from 5 females, and all within a seven-day collection period. Each of 20 bags received 15 eggs. The bags were kept together on a large table away from direct sunlight, their positions on the table were changed frequently. Each bag received a code number. Room temperature was recorded daily during mid-morning. Foodplant was changed every four days and body lengths of caterpillars were measured usually every two days. Head capsules were always collected and stored separately for

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Fig. 3. Second-growth habitat of Morpho peleides at Cuesta Angel in Costa Rica (montane tropical forest): (A) high infestations of the caterpillars are frequently encountered on second-growth leguminous genera such as Mucuna and Machaerium which are very abundant along the sides of the road cut; (B) fifth-instar caterpillar in its cryptic resting position on a dead grass stem next to a Machaerium plant (16

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Table 2. A summary of some records for caterpillar foodplants in the genus Morpho.

Foodplants

each bag. One half of the bags received Mucuna and the remaining ten received peanut. General day-to-day husbandry of the cultures also included removal of fecal material, dead caterpillars (recording the date of death), and periodic wiping of excess condensation. Three trained people performed the "sampling" of caterpillars and general husbandry, but the same person seldom sampled the same six or seven bags on two consecutive dates. Caterpillars were transferred as active prepupae to sturdy potted plants for pupation. Pupae were kept under the same room conditions as caterpillars and eclosion dates were recorded. Pupal size (length and width), but not weight, was recorded. Pupae of peanut-reared individuals were kept separate from those of Mucuna-reared individuals. The wing-span of all emerging adults was also recorded.

The same procedures were used for the subsequent study at Lawrence University, with the exception of a reduction in the number of caterpillars studied. There were 125 caterpillars reared on Mucuna and 100 caterpillars reared on peanut (seeds obtained from Olds Seed Co., Madison, Wisconsin). The cultures (Fig. 2) were kept in an air-conditioned laboratory whose mid-morning temperatures ranged from 21.8 to 24.0°C. The eggs used to establish the Lawrence cultures were obtained from four

August 1972). Note: As of late March 1973, this section of road cut has been drastically widened by bulldozers, destroying a great deal of available roadside food-plants for Morpho.

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females captured in Costa Rica and brought to Appleton within a few days; the eggs were laid over an eight-day period. Prior to this time, thriving cultures of both peanuts and Mucuna (seeds brought from Costa Rica) were established at Lawrence for the sole purpose of rearing peleides and other Morpho.

Results

In the original pilot study, all of the caterpillars of peleides completed development successfully, but all of the polyphemus caterpillars died during the late fifth instar. Developmental time was not followed carefully in this study.

In the two major studies, there were no differences in the performance of caterpillars of M. peleides on Mucuna and peanuts (Table 1). Caterpillars are apparently equally viable on both foodplants in the first generation. The various measurements given in Table 1 are adequate indicators of performance for caterpillars and pupae. The size range of adults reared on the two plants was very similar with no consistent trends towards increased (or decreased) wingspan on either plant. Very interesting is the similar success in rearing peleides in Costa Rica and Wisconsin (Table 1). Again, there were no consistent trends in the data supporting the view that rearing was more (or less) successful at either place. There was also no difference in the number of eggs in the bodies of virgin females reared on either foodplant: Mucuna-reared females less than two days old contained 61 ± 7.5 (N = 55) eggs and peanut-reared females contained 60 ± 5.8 (N = 46). Duration of older instars and the sizes of caterpillars and pupae were less variable for peanut-reared individuals (Table 1).

Wild-caught healthy females in captivity will not lay eggs on peanut leaves while the same females will readily lay many eggs on Mucuna leaves under the same conditions. An attempt to obtain oviposition on peanut from peanut-reared mated females has not been done since I have been unable to achieve successful mating of peleides in captivity.

In the pilot study on foodplant acceptance with Wisconsin legumes, it was found that second instar larvae readily accepted and survived on both Robinia and Gleditsia. This very interesting preliminary result will prompt me to conduct a large-scale controlled rearing study using several Wisconsin trees in the future.

Discussion

A representative portion of the known foodplants for the caterpillars of Central and South American (Brazilian) Morpho is given in Table 2. If we assume for the moment that Morpho and flowering plants evolved

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at about the same time, the caterpillar-foodplant radiation of the genus can be discussed in a speculative but interesting manner. Based on present fragmentary knowledge of foodplants used by Morpho (Table 2), I propose that there were several different adaptive radiations within the genus, but that one of these was far greater than the others. Borrowing from the recent phylogenetic scheme of flowering plant evolution discussed in Takhtajan (1969), the several "minor" foodplant radiations of Morpho included the families (in parentheses; see Table 2) in these orders: Ranunculales (Menispermaceae), Laurales (Lauraceae), Theales (Guttiferae), Urticales (Moraceae), Euphorbiales (Euphorbiaceae), and Poales (Gramineae). But it is the derivative orders of the Saxifragales that formed the major basis for foodplant radiation in Morpho. The following orders and families very close to, or derived from, the Saxifragales (according to Takhtajan, 1969) contain foodplants of several Morpho (Table 2): Fabales (Leguminosae), Sapindales (Sapindaceae), Mrytales (Mrytaceae), Geraniales (Erythroxylaceae), and Rhamnales (Rhamnaceae). No other clear pattern of foodplant exploitation exists for Morpho since the minor groups are scattered across the phylogenetic scheme. Of course, this may be an artifact of the scheme proposed by Takhtajan; but departures would be minor and the same general pattern should result. Also note that the Rutales (which contains Rutaceae) are also derived from Saxifragales; in March 1973,1 discovered several second instar larvae of peleides feeding on a vine in the Rutaceae in the under-story of a small semideciduous wet forest in Guanacaste, Costa Rica. Since the plant specimen was sterile, no further identification was made. These comments on foodplant radiation assume that the larval food-plant records of Morpho are accurate at the family level. It may be beneficial to re-check in the field some of the scattered records, especially ones like Moraceae and Euphorbiaceae (Table 2).

Thus it emerges that some species of Morpho, including members of the achielles complex (which includes peleides) not only feed on Leguminosae, but may in fact be preadapted to exploit other genera and species within this family. The data presented here for peleides on peanuts bear this out, if we assume that peanuts are not in fact used as foodplant in the wild. Such a preadaptation could result in species like M. peleides feeding on peanuts and other legumes. Being herbaceous, peanuts may, in fact, be an easier foodplant for digestion by caterpillars, as suggested by the reduction in the variability of developmental time and size during the ontogeny of M. peleides on this plant. This may be due to greater consistency of the leaves in this annual plant. In the wild, even very young caterpillars of M. peleides are found on very old and tougher leaves of foodplants (Young & Muyshondt, 1973). That M. peleides in

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particular may be especially preadapted for the exploitation of many different legumes is also suggested by the large number of foodplant species and genera that this species is found on locally in second-growth plant communities in Costa Rica. Here, the caterpillars are generally found on a variety of leguminous vines and small shrubs even along road sides where young second-growth is frequently encountered (Fig. 3). As with peanuts in the laboratory, the developmental time and size range of individuals reared on these different natural foodplants are very similar (Young & Muyshondt, 1973), indicating that the species performs equally well on all of these plants. If we assume that the deaths of the M. polyphemus caterpillars feeding on peanuts in the small pilot study was due to some metabolic or physiological incapacity to handle this food properly, it is possible that this species is less preadapted for generalized leguminous feeding than M. peleides. Partial support for this idea comes from the known foodplant data for M. polyphemus in El Salvador, and its close relative, M. catenarius, in Brazil (Table 2). The majority of foodplants are not legumes (Table 2) and these butterflies may have followed a different evolutionary path for foodplant exploitation from that of M. peleides and its close relatives. Of course, the data here for M. polyphemus are very preliminary and more extensive rearing tests on peanuts must be performed to demonstrate reduced performance on this plant. In light of these preliminary findings and their implications concerning evolutionary divergence in caterpillar foodplant exploitation, it could be very interesting to conduct similar rearing studies of other generally non-leguminous feeders of Brazilian Morpho (anaxibia, mena-laus, hercules, aega, etc.—Table 2) with peanuts.

Summary

(1)   Caterpillars of the neotropical butterfly, Morpho peleides were reared in Costa Rica and Appleton, Wisconsin on Mucuna urens (a known natural foodplant) and peanuts, Arachis hypogaea, under identical conditions. While both plants are in the Leguminosae, the assumption was made that peanuts would be a novel foodplant for this butterfly since no records of it feeding on peanuts in tropical America are known. Furthermore, all of the known leguminous foodplants of the butterfly are woody perennials and not herbaceous annuals.

(2)   Using various measures of performance such as egg-adult developmental time and body size, it was found that caterpillars were equally viable on either plant. There was less variability in performance among caterpillars reared on peanuts.

(3)   A pilot study of rearing caterpillars of Morpho polyphemus on peanuts showed that they succumb in the fifth instar. But since a very

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small number of caterpillars were studied, it could not be determined if these deaths were accidental or actually due to improper handling of the food by the digestive machinery of the caterpillars. This species in the wild feeds primarily on a variety of non-leguminous foodplants and it may eventually be shown that the caterpillars are less conducive to leguminous feeding.

(4)  Based on foodplant records and the phylogeny of flowering plants, it is speculated that the major adaptive radiation of Morpho occurred on plant families within various orders close to, or derived (in evolutionary time) from, the Saxifragales. Of these orders and families, the major array of foodplant exploitation is in the Leguminosae, a member of the Fabales.

(5)   The idea is advanced that M. peleides is preadapted to feed on many genera and species of legumes locally and there are some field data to support this view (Young & Muyshondt, 1973). Other legume-feeding species support this view (Young & Muyshondt, 1973). Other legume-feeding species of Morpho may show similar ecological flexibility while generally nonleguminous feeding species may not.

Acknowledgments This research was supported by a grant from the Bache Fund of the National Academy of Sciences (No. 120), and partially by National Science Foundation Grant GB-33060. Logistic support in Costa Rica was provided by the Costa Rican Field Studies Program of the Associated Colleges of the Midwest (A.C.M.). Roger Kimber and John Thomason (Lawrence University) assisted with the rearing studies. Keith S. Brown, Jr., and Woodruff W. Benson read a revised version of the manuscript and made several helpful suggestions.

Literature Cited

Barcant, M. 1971. The Butterflies of Trinidad and Tobago. Collins, London. d'Aranjo e Silva, A. G., C. R. Gonzalves, D. M. Galvao, A. J. L. Gonzalves, J.

Gomes, M. Nascimento Silva & L. de Simoni. 1968. Quarto catalogo dos

insectos que vivem nas plantas do Brasil; seus parasitas e predadores. Ministerio

de Agricultura, Rio de Janeiro. Leon, J. 1968. Fundamentos Botanicos de los Cultivos Tropicales. Inst. Inter-

Amer. Ciencias Agriculas de la OEA, San Jose, Costa Rica. Otero, L. S. 1971. Instrucoes para criacao da borboleta "Capitao-do-mato"

(Morpho achillaena) e outras especies do genero Morpho ("Azul-seda," "Boia,"

"Azulao-branco," "Praia-grande"). Inst. Brasileiro Desenvolv. Florestal (Rio

de Janeiro), 27 p. Takhtajan, A. 1969. Flowering Plants. Origin and Dispersal. Smithsonian Press

(English translation), Washington, D.C., 310 p. Young, A. M. & A. Muyshondt. 1972. Biology of Morpho polyphemus in El

Salvador. J.N.Y. Entomol. Soc. 80: 18-42. ----------. 1973. Notes on the biology of Morpho peleides in Central America.

Carib. J. Sci. 13: 1-49.