Swallowtails

Papilionidae.

Large (WS of most 7-11 cm), colorful, and graceful in flight, the swallowtail butterflies (so-called from the taillike extensions

Figure 10.15. SWALLOWTAIL BUTTERFLIES (PAPILIONIDAE). (a) Kite (Eurytides bellerophon). (b) Kite (Eurytides philolaus), larva, (c) Giant swallowtail, pupa, (d) Giant swallowtail (Papilio thaos) (e) Giant swallowtail, larva, (f) Aristolochia swallowtail (Parides iphidamas). (g) Aristolochia swallowtail, larva.

of the apices of the hind wings of some genera) adorn the Neotropics. Color patterns vary, but there is frequently a red-tinted, eyelike spot at the inner notch of the hind wing. Their caterpillars are all naked, without spines or visible hairs but sometimes with tubercles, and are somewhat club shaped, with the thorax enlarged. When disturbed, the larvae arch their backs and evert an odoriferous forked organ (osmeterium) from behind the head which is a deterrent device (Eisner et al. 1971, Lopez and Quesnel 1970, Young et al. 1986). The chrysalids mimic wood fragments with their angular form (two projecting points on the head) and rough brown or greenish integument. They rest upright, fastened to a terminal silk button and leaning back into a silken girdle.

There are three major types of swallowtails based on form and habits (Hancock 1983). The kites (pages, zebras, swordtails, Leptocircini, e.g., Eurytides; fig. 10.15a) are smaller than most (WS 7 cm) and have pale, thinly scaled, often white wings, with thin, transverse, black stripes; the tails are extra long and flexible. The larvae (fig. 10.15b) are usually green and smooth, and they feed on species of the custard apple family (Annonaceae). These are forest dwellers, and the males are common participants in the clouds of butterflies seen drinking from wet sand along watercourses.

The sun-loving true swallowtails (Papi-lionini, Papilio; fig. 10.15d) are the largest of the group (WS to 12 cm) and variously marked, although most are black with broad bright yellow bars through the middle of the wings and crescent-shaped spots bordering the outer margin of the hind wing. A few are "tiger marked" and mimic similarly colored heliconian and ithomiine models. Tails are lacking in the latter but are nearly always present in true swallowtails, although short. The rare Papilio ho-merus of Jamaica is the largest tailed swallowtail in the world (WS to 15 cm). The larvae (fig. 10.15e) are mottled brown and cream streaked, simulating bird droppings, and often congregate for mutual protection. Food plants are varied but often are of the pepper (Piperaceae) and citrus families (Rutaceae), the latter including orange, lemon, and lime. On citrus, those of certain species (Papilio cresphontes, P. andraemon, P. anchisiades) sometimes constitute pests and are known to fruit growers as "orange puppies" or "orange dogs" (Lawrence 1972). Papilio chrysalids often mimic broken twigs (fig. 10.15c).

Aristolochias ("poison eaters," pharma-cophagous swallowtails, Troidini) are moderate-sized (WS 7-9 cm), mostly without tails, and inky black with red or magenta color fields in the center of the hind wing and green (blue or yellow) areas near the base of the fore wing (Parides; fig. 10.150 or dull, greenish-black with splotches of vellow mostly on hind wings (Battus). These swallowtails are partial to shade and moisture and are consummate forest insects where the larvae (fig. 10.15g) feed on their pipe vine (Aristolochia, Aristolochia-ceae) hosts. These plants contain toxic alkaloids sequestered by the caterpillars gild transmitted to the adults, making them unpalatable. Many serve as models in Batesian and Miillerian mimicry complexes (Young 1971). The tuberculate larvae are also protected by these chemicals, a fact they seem to advertise with red-orange or yellow streaks, conspicuous against an otherwise completely black body. The pupae are flared out laterally along the edges of the wing cases (Young 1977).

There are more than ninety swallowtail species in Latin America (d'Abrera 1981, d'Almeida 1966); the family occurs as far south as central Chile and northern Patagonia (Slansky 1973). The biologies of most are still unknown in spite of the attention this attractive group has received from collectors and hobbyists. Some information is available on the several species, including Papilio homerus, above, considered possibly in danger of extinction by the International Union for the Conservation of Nature (Collins and Morris 1985).

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