AMERICAN MUSEUM Novitates PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, N.Y. 10024 Number 301 1, 43 pp., 85 figures, 4 tables June 26, 1991 Cladistics and the Biogeography of Two Trans-Caribbean Hairstreak Butterfly Genera: Nesiostrymon and Terra (Lepidoptera, Lycaenidae) KURT JOHNSON' ABSTRACT Two sister genera composed of notably non- T. hispaniola Johnson and Matusik (southern His- vagile members distributed both in the Greater paniola); on the mainland, type species T. tera Antilles and mainland Neotropics are revised. (Hewitson) (central Mexico to Colombia); three Cladistic classification is employed from numer- species transferred from Thecla, T. calchinia ical analysis (PAUP, Swofford) ofthe ingroup and (Hewitson) (upper Amazon), T. cana (Hayward) three outgroups restricted to the mainland. Ne- (northwest Argentina), T. chilica (Schaus) (south- siostrymon includes five species: in the Antilles, east Brazil, Paraguay); and one new species, T. type species N. celida (Lucas) (with three interis- andevaga (Ecuador). Comparison of area clado- land subspecies-nominate [Cuba] N. c. aibonito grams of Nesiostrymon and Terra shows congru- (Comstock and Huntington) [Puerto Rico and ence of plesiotypic Antillean elements and apo- northern Hispaniola], N. c. baorucoensis, new sub- typic members occurring in Central America and species [southern Hispaniola]), and N. shoumatoffi South America, respectively. These are construed (Comstock and Huntington) (Jamaica); on the as more compatible with late-Cretaceous-Tertiary mainland, pan-Neotropical N. celona (Hewitson) vicariance of a proto-Greater Antilles from the (transferred from Thecla) and two new insular spe- Central and South American regions than a com- cies, N. milleri (cloud forests, Aragua, Venezuela) plex dispersal explanation requiring numerous and N. australivaga (scrub-steppe, Mendoza, Ar- concordant dispersals. gentina). Terra includes six species: in the Antilles, ' Research Associate, Department of Entomology, American Museum of Natural History. Copyright © American Museum of Natural History 1991 ISSN 0003-0082 / Price $5.00 2 AMERICAN MUSEUM NOVITATES NO. 3011 INTRODUCTION Nesiostrymon Clench (1964) and Terra tory (FMNH); Hope Entomological Collec- Johnson and Matusik (1988) are sister genera tion, Oxford University (HEC); Instituto of notably nonvagile "hairstreak butterflies" Miquel Lillo (Tucuman, Argentina) (IML); (Theclinae, Eumaeini) occurring both in the Los Angeles County Museum (LACM); Mil- Antilles and the mainland Neotropics. Nu- waukee Public Museum (MPM); Museum merical cladistic analyses associated with the National d'Histoire Naturelle (Paris, France) description of Terra indicated that it and Ne- (MNHN); Museo Nacional de Historia Nat- siostrymon are the sister group of three eu- ural (Santo Domingo, Dominican Republic) maeine assemblages restricted to the main- (MNDR); Zoologisches Museum der Hum- land (Johnson and Matusik, 1988). Observing boldt Universitiit zu Berlin (ZMH). Speci- the local habitat restriction and widely dis- mens were also examined from three private junct distributions ofNesiostrymon and Ter- collections with extensive Antillean or aus- ra taxa, Johnson and Matusik (1988) sug- tral South American holdings: Robert C. Ei- gested that Antillean species of these genera sele Collection (Jujuy, Argentina) (REC); Da- (along with two other recently discovered vid Matusik Collection (Skokie, Illinois) south Hispaniolan endemics) most likely "re- (DM); and Albert Schwartz Collection (Mi- flect a tectonic relationship between ... ami, Florida) (ASC). regions . on the northern edge of the Ca- ribbean plate." SYSTEMATICS Recent biogeographical studies (Shields and Phylogenetic Analyses ofNesiostrymon and Dvorak, 1979; Buskirk, 1985; Johnson and Terra: Johnson and Matusik (1988) used nu- Descimon, 1989; Miller and Miller, 1989) merical cladistic analysis (PAUP; Swofford, recognized a component of Antillean Rho- 1985) to establish the monophyly of Nesios- palocera more suggestive of an ancient vi- trymon, Terra, and certain outgroup taxa of cariant origin than the prominent waif-dis- the lycaenid grade "Thecla" (sensu Bridges, persal origin attributed to the fauna by early 1988) (fig. 1; tables 1, 2). Focusing primarily workers (Comstock and Huntington, 1949; on the Caribbean region, Johnson and Ma- Scott, 1972; Riley, 1975; Brown, 1978). Mil- tusik (1988) distinguished Antillean mem- ler and Miller (1989), summarizing a prob- bers of Nesiostrymon and Terra and listed able vicariance and dispersal model for mainland relatives from the "Thecla" grade. Antillean butterfly origins, included Nesio- Subsequently, Johnson (1991) published a strymon and Terra as one of nine butterfly nomenclature for outgroup taxa (figs. 84, 85). groups most probably arising from late Cre- The cladistic study of Johnson and Ma- taceous-Eocene vicariance. tusik (1988) indicated that Terra and Ne- This study reports a cladistic taxonomy of Neotropical Nesiostrymon and siostrymon form a monophyletic group Terra and distinguished from outgroups by six synapo- presents the ecological and ev- biogeographic morphies of the wings, genitalia, and termi- idence supporting a vicariant origin for An- tillean members of two nal abdominal morphology (table 1: charac- these hairstreak but- ters 2, 4-6, 12, and Terra terfly genera. 14). taxa share a salient apomorphy: the prominent sclero- tized bulb protruding ventrally between the MATERIALS AND METHODS cephalic and caudal elements of the ductus COLLECrIONS bursae (table 1, character 11). Nesiostrymon taxa share a specialized prominently pronged Specimens examined included samples tergite 8 in males (table 1, characters 1, 9). from the Allyn Museum of Entomology, High consistency values (fig. 1) for clado- Florida Museum of Natural History (AME); grams result from the various very distinctive American Museum of Natural History morphological characters which separate (AMNH); British Museum (Natural History) these taxa (e.g., the incised posterior cavity (BMNH); Carnegie Museum of Natural His- ofmale tergite 8, distribution ofmicrotrichia, tory (CMNH); Field Museum ofNatural His- etc.). "Outgroup" and "Lundberg outstate" 1991 JOHNSON: HAIRSTREAK BUTTERFLY GENERA 3 AB C D A B CD E F 5-' - 1 4 12 ' 2,4,5,6,12,1 4 1 , 9 T' caption, A caption, B caption, C (Tb. 1) 2,4,5,6,12,1l4 Fig. 1. Cladogram ofNesiostrymon (D), Terra (C), and relatives (A, B) (Johnson and Matusik, Fig. 2. Ingroup cladogram ofNesiostrymon (A, 1988). Four-taxon statement derived from parsi- B, C) and Terra (D, E, F). Six-taxon statement monious distribution ofunweighted characters and derived from parsimonious distribution of un- rooted using (1) outgroup[s] described in text (con- weighted characters and rooted using Lundberg sistency index = 0.923) and (2) Lundberg method outstates based on monophyly of Nesiostrymon (Swofford, 1985) based on presumed primitive and Terra, figure 1. Consistency index = 0.909. states listed at bottom oftable 2 (consistency index Apomorphies are specified by horizontal bars and = 0.889). Apomorphies for Nesiostrymon and Ter- represent characters enumerated in tables 3 and ra specified by horizontal bars enumerated from 4. Synapomorphies noted for Nesiostrymon/Terra 1 tables and 2. Outgroups and their apomorphies: are from figure 1, tables 1 and 2. Terminal groups A, B. Outgroup rooting preferred " Thecla uzza include A, N. celona/milleri/australivaga; B, N. complex" (fig. 84) as sister group ofNesiostrymon! celida; C, N. shoumatoffi; D, T. hispaniola; E, T. Terra based on characters 9, 10 with " Thecla cel- tera; F, T. andevaga/chilica/calchinia/cana. mus complex" (fig. 84) as the outgroup; Lundberg rooting preferred the opposite based on characters, 1, 3, 7, 13. C. "Thecla" outgroup (fig. 85), char- acters enumerated by Johnson and Matusik, 1988. demic T. hispaniola being the most primitive in character. Based on these results, species- level taxonomies for Nesiostrymon and Terra (Swofford, 1985) rootings (fig. 1) give iden- are enumerated below. tical results concerning the monophyly of Terra and Nesiostrymon. TAXONOMY OF NESIOSTRYMON and To determine a cladistic classification of TERRA species in Nesiostrymon and Terra, parsi- GENUS NESIOSTR YMON CLENCH monious distributions of characters were constructed for shared characters of species Figures 3-32, 57, 59-68 in each genus (fig. 2, tables 3, 4). Monophyly Nesiostrymon Clench, 1964: 248, 251. Brown and of the ingroup was assumed from Johnson Heineman, 1971: 4; 1972: 232. - Scott, 1986: and Matusik's (1988) results; species criteria 21. - Riley, 1975: 101. - Bridges, 1988: 1.74, were based on standard taxonomic proce- II.77. - Johnson and Matusik, 1988: 236. - dures involving consistent in Schwartz, 1989: 240. - Miller and Miller, 1989: differences 245. characters of the wings and genitalic and ter- gal morphology. Table 3 lists the apomorphic DIAGNOSIS: Compared to all Eumaeini: and plesiomorphic states ofcharacters delim- male tergite 8 modified to a "subcordate in- ited from the final rooted tree (fig. 2). This cised posterior cavity" (the "sipc" sensu Field, analysis indicates the following: Nesiostry- 1967a, 1967b; Johnson, 1988a, 1989a, 1989b; mon is a monophyletic group with two nested Johnson and Matusik, 1988) terminating in sets of taxa, the Jamaican endemic, N. shou- a dorsally produced lobe or prong, genital matoffi, being the most primitive in charac- valvae multiplanar with protruding, winglike ter; Terra is a monophyletic