] OURNAL OF

THE LEPIDOPTERISTS' SOCIETY

Volume 14 1960 Number 3

HARMONIZATION OF CONCEPTS OF HIGHER CLASSIFICATION OF THE PAPILIONIDJE

by EUGENE MUNROE and PAUL R. EHRLICH

Previous work carried out independently by us on the basis of largely different sets of characters (Ehrlich, 1958; Munroe, 1953, and in press) led to interpretations of papilionid classification that were in harmony in major outline, though they differed in several points. Consultation and joint examination of certain characters has permitted resolution of all the points of difference and of some points of uncertainty in our previous arrangements. The present paper can be considered a supple­ ment to and revision of our individual contributions on this subject. Our earlier classifications agreed in considering the BaroniimB, Parnassiinre and Papilioninre as subfamilies of Papilionidre, in considering the phyletic separation of Baroniinre as considerably antedating that of the Parnassiinre and Papilioninre, in considering the Zerynthia and Parnassius groups as not fundamentally distinct, and in associating Lamproptera with the Graphiini and Cressida and Euryades with the Parides complex. We differed mainly in that (1) EHRLICH classified Teinopalpus in a separate tribe of the Papilionill3~, whereas MUNROE placed this genus in the Graphiini; and (2) EHRLICH placed Battus and provisionally Troides and Ornithoptera in the Papilionini, whereas MUNROE placed them with Cressida, Euryades and Parides. Also, (3) although we are agreed that genera have been far too finely divided in recent work on several groups of butterflies, MUNROE divided the genera Parides and Graphium as understood by EHRLICH, who did not carry his work to the generic level. This division was based on genitalic and other characters. MUNROE attempted a more detailed phylogenetic classification than did EHRLICH, whose interests were in a broader field. Some points of major uncertainty remained, however, in MUNROE'S classification. The most important of these were: (1) the phylogenetic relationship of the

169 170 MUNROE & EHRLICH: Papilionid;e Vo1.l4: no.3

Parnassiime and the Troidini; (2) the relationship of the red-tuberculate Aristolochia-feeding larval type to the green, Lauracere-feeding type; and (3) the origin and internal phylogeny of the Papilionini.

POINTS OF PREVIOUS DIFFERENCE

The points of difference seem best resolved as follows:- (1) Teinopalpus appears to have real affinities wlith the most primi­ tive Graphiini, but it differs in the inflation of the frons and the associated hypertrophy of the palpus, in lacking sclerotized patagia, in having smaller tentorial crests, in the weak development of the cubito-vannal cross-vein, in the sexual dimorphism and specialization of the pattern and wing-shape, in the atypical wing-venation, and in the reduced antennal scaling. It appears to be a matter of individual preference whether the differences or the resemblances should be emphasized. Possibly the best solution is to recognize Teinopalpiti and Graphiiti as subtribes of Graphiini. Teinopalpus lacks the spine of the prodiscrimen, as do other Graphiini except Dabasa. The statement to the contrary in Ehrlich (1958) resulted from an error in proofreading. (2) Troides and Ornithoptera, as stated by MUNROE and hinted by EHRLICH, are typical members of the Cressida - Parides complex. The name Troidini is to be preferred over Cressidini for the union of the two tribes recognized by FORD, as names based on Troides are older in the literature and FORD's Troidini form by far the larger constituent of the combined group. Ornithoptera and Troides are undoubtedly derived from a common ancestor more like Troides than Ornithoptera, for Troides has no specialization of pattern or wing-shape that is not found or suggested in Ornithoptera, whereas Ornithoptera has greatly specialized pattern and strong sexual dimorphism and has lost the Parides-like sex-scaling on the anal margin of the hind wing, still evident in Troides, and has substituted a new set of sex-scaling on the upper surface of the fore wing. The retention of slight sclerotization of the patagia and the longer free course of Rl indicate a separation of the Troides-Ornithoptera complex from a position near or below the base of the present genus Parides, but this conclusion requires confirmation from examination of a wider range of species. Battus is far more widely different. The narrow spinasternum and the absence of definite sensory pits on the undler surface of the antenna indicate a separation of Battus from the remaining Troidini before the separation of the Cressida - Euryades and the Parides - Troides stocks. These four genera agree in having the two specializations, broad spinastemum and definite sensory pits. On the other hand, the detailed structurel correspondence of the Aristolochia-feeding, fleshy-tubercled 1960 Journal of the Lepidopterists' Society 171 larva, of the arcuate, flanged pupa, and of the male genitalia indicates beyond possibility of coincidence the direct relationship of Battus with the other Troidini. Battus is, however, by far the most distinctive genus of the tribe, and it is probably best here also to recognize two subtribes, Battiti and Troiditi. (3) The generic separations advocated by Munroe appear to be reason­ ably founded. In the Troidini, Pachlioptera, comprising P. hector, aristolochi:e, polydorus and allies, is a compact group, certainly closely related to Parides and presumably derived from it, but differing in the radical character of near-abortion of the valves and pseuduncus and enlargement and sclerotization of the socii apparently to take over a clasping function. These differences are supported by minor differences in the structure of the female genitalia and in the larvre and the pupre. Cressida and Euryades are not closely related to Pachlioptera as assumed by FORD on the basis of an observation copied from TALBOT and based in the first place on misinterpretation by the latter of an external examina­ tion of the male genitalia. In the Craphiini, division of the New World Kite Swallowtails (Eurytides), which, like the related Old World genus Lamproptera, retain the uncus and socii as a composite structure, from the main group of Old World species (Graphium), in which the uncus is aborted, appears to be satisfactory and to define homogeneous groups. The three groups of Old World Kite Swallowtails that retain the free Rl that is characteristic of most Eurytides also all have peculiar genitalia. The Australian species leosthenes retains the uncus weakly as a finger­ like structure; MUNROE has proposed the genus Protographium for this species. Protographium is apparently a relict connecting link between the large genera Graphium and Eurytides. The payeni - evan group i!> very distinct in genitalia from Graphium; it resembles it in having lost the uncus, but has large horny socii, articulated firmly with the eighth tergite; it also differs from Graphium in the short cell and distorted discocellulars, in the weak sclerotization of the patagia and in having a small spine on the prodiscrimen, lacking in Graphiu,rn. This group forms a very distinct genus for which the name Dabasa is available. The European species podalirius, together with its Tibetan representative podalirinus, constitute the third group with free R1 • In this group the male genitalic structure is fundamentally similar to that of Graphium, but the valve is very simple and unusually elongate. The larva is unusual in appearance and food plant and has segmental red spots. This com­ bination of characters would support separation of these two species as the genus Iphiclides. This separation has the advantage of making

Graphium homogeneous for anastomosis of Sc and R l . However, the separation is a weak one, and some students may prefer to unite these 172 MUNROE & EHRLICH: Papilionid;c Vo1.l4: no.3 two genera. To summarize, these separations represent either rather large phyletic cleavages (Eurytides, Graphium, Dabasa) or distinct and well-characterized side-lines or relics (Pachlioptera, lphiclides, Protographium). They are on a considerably coarser plane than the divisions currently fashionable in such groups as the Blues and Coppers. With the possible exception of the separation between lphiclides and Graphium, they should be retained.

POINTS OF PREVIOUS UNCERTAINTY

(1) Relationship of Troidini to Parnassiinx and to other Papilioninx. The key to this problem appears to be the cubito-vannal vein. This was previously considered by MUNROE to be a primitive character, but we now believe this interpretation to be erroneous. No similar vein is found in other families of butterflies, so far as our reading extends; it is certainly lacking in a variety of forms examined by us. No comparable vein is found in higher groups of moths, including Cossidre and Castniidre. The vein is also absent or rudimentary in the two other subfamilies of Papilionidre, Baroniinre and Parnassiinre. The nearest parallel we have found outside of Papilioninre is the sclerotized root of 1st V found in Limenitis and certain other Nymphalidre. It is possible that the vein present in Papilioninre is such a root stalked for a certain distance with Cu; alter­ natively it may be a I>tructure formed de novo. It is noteworthy that in Teinopalpus, which has perhaps the most primitive genitalia of any papilionine, the vein is weakly developed. At any rate it seems highly probable that this vein is an unusual specialization, characteristic of the Papilioninre, and that it indicates with great probability that this sub­ family is a natural and monophyletic group, as would be suggested by their considerable uniformity in wing-venation and palpal structure, and by the possibility of harmonizing the different larval and pupal types without undue stretching of the imagination. As the Graphiini have more primitive genitalia, legs and antennre than the Troidini, which resemble Parnassiinre mainly in the early stages and in the presence in certain species of a sphragis, we must conclude that the Troidini are derived from an ancestor which on the defining characters of scaled, legs, scaled antennre and free, complete male genitalia we would be forced to refer to the Graphiiti. There is therefore no question of direct relationship of the Parnassiinre and Troidini. There must have been a graphiine intermediary, though probably one more closely similar to generalized Troidini and Parnassiinre than are existing species of Graphiini. We may recall at this point that the existing troidine genus Battus has apparently never acquired two of the most prominent speciali- 1960 Journal of the Lepidopterists' Society 173 zations of the remaining Troidini. This involves the corollary conclusion that the Parnassiinre-like features of Euryades and Cressida are secondary; this applies particularly to the narrowed, Parnassius-like valve. The sphragis in these genera and in certain primitive Parides may indeed be derived from the same source as that of Parnass:[us, though perhaps only as a common tendency, rather than as an overt character in an un­ broken line. (2) Relationship of red-tuberculate, Aristolochia-feeding larva to green, sometimes brown, sometimes spinose, Lauracece - OT Rutacece - feeding larva. The solution of this problem is bound up with that of the previous one. If we assume, as we apparently must, that the Papilioninre are a homogeneous, monophyletic group, it is ascribing too much to coinci­ dence to suppose that the red-tuberculate, Aristolochia-feeding larva has been independently developed in the two groups Parnassiinre and Troidini from smooth, green, Lauracere-feeding, skipper-like or pierid­ like ancestors. On the other hand, it is not hard to imagine a reversion from Aristolochiacere to the lauraceous food-plant that characterizes several primitive hesperiids and pierids. The acquisition, perhaps several times, of a cryptic, green or brown, coloration would also be easy. It may be noted further that larvre of many species in Craphiini and Papilionini retain red spots and/or tubercles in the final instar, while all known species are tuberculate and many red-spotted in earlier instars. This permits a decision between the alternative hypotheses presented in MUNROE'S paper. The red-tuberculate, Aristolochia-feeding larva must be primitive, at least for the Parnassiinre and Papilioninre. It follows that the primitive Craphiini must have had red-tubercled larvre, probably somewhat Zerynthia-like in aspect, and feeding oUi Aristolochia. The hearsay reports of the larva of Lamproptera that were cited by MUNROE (in press) appeared to fill this need, but unfortunately Mr. KENT WILSON (in litt.) informs us that these reports were erroneous and can be dis­ regarded. Mr. WILSON'S description of the early stages of Lamproptera will be awaited with interest. Larvre of the Eurytides lysithous group have tuberculate and spotted larvre, but there is a possibility of mimicry of Parides larvre. In our present state of knowledge it cannot safely be assumed that all red spots and all tubercles are homologous. Comparative morphological study of a wide range of larvre is badly needed. It may be noted parenthetically that the larva of the primitive though aberrant Teinopalpus is described as being smooth and green. It may be repeated for good measure that we have no knowledge or incomplete knowledge of several of the really critical life histories for phylogenetic interpreta­ tion, viz.: Teinopalpus, Lamproptera, and Dabasa from Asia and Baronia from Mexico. MUNROE & EHRLICH PAPILIONIDJE

Parides Pachlioptera Dabasn PAPILIONINI

Iphiclides ~-----JI Graphium Protographium Troides Ornithoptera I

Eurytides Lamproptera Cress ida Euryades I

Battus Teinopalpus I I BATIITI TROIDITI GRAPHI II TI TEINOPALPITI I I I ~ TROIDINI GR,APHIINI I I PARNASSIINAE PAPILIONINAE

BARONIINAE

PAPILIONIDAE PIERIDAE IL--___,.--- __~

Apparent sequence of separation of papilionid lines. The significant feature of this diagram is the order of the bifurcations.

174 1960 Journal of the Lepidopterists' Society 175

(3) Origins and internal phylogeny of the Papilionini. This problem continues to present many points of uncertainty. The most probable origin of the tribe still appears to be from the higher Graphiini. The presence of the spine of the discrimen is a point of similarity between Papilionini and Troidini that can be added to the well-known ones. This spine is lacking, however, in Battu8, the troidine genus that has other Papilio-like characters. Dabasa, unlike other Graphiini, has the spine, though weakly. This would support the possibility that this genus arose close to the point of separation of Papilionini hom Graphiini. On the whole it seems likely that the spine has been acqUiired independently in the Papilionini and the Troidini. It is obvious that final answers on the precise ancestry of the Papilionini are not possible on the evidence available to us. Still less can the vexed questions of the internal phylogeny of the Papilionini be properly resolved. This must await the results of more comprehensive studies than time or material have permitted us to make.

References Ehrlich, Paul R., 1958. The comparative morphology, phylogeny and higher classification of the butterflies (Lepidoptera: Papilionoidea). Univ. Kansas sci. bull. 39: 305-370. Munroe, Eugene, 1953. The phylogeny of the Papilionid::e. l'roc. 7th Pacific sci. congr., Auckland, 1949 4: 83-87. . Munroe, Eugene, in press. The generic classification of the P.1pilionid::e. Canadian ent., supplement 17.

(EGM) Entomology Research Institute, Research Branch, Canada Agriculture, Ottawa, Ont., CANADA and (PRE) Dept. of Biological Sciences, Stanford University, Stanford, Calif., U. S. A.

A NEW ENTOMOLOGICAL SERIAL The Society Library has received the first two numbers of Esakia published by the Hikosan Biological Laboratory, Faculty of Agriculture, Kyushu University, Fukuoka, Japan. They include nine short papers by present or former members of the laboratory shaff; among these are two by HIROSHI KUROKO describing new microlepidoptera (Gracilariid.:e and Cosmopterygid.:e). The issues are well illustrated by photos and line drawings. Members desiring further information are advised to write to the Chief of the Laboratory, Professor KEIZQ YASUMATSU. P. F. BELLINGER