Contribution to the Taxonomy of the Panamerican Genus Fallceon (Ephemeroptera: Baetidae)

-The baetid mayfly genus Falkceon is currently known from Central America, the Greater Antilles, Mexico, and the United States, and includes eleven nominal species: F. al carrazae, new combination, F. eatoni, F. fortipalpus, new species, F. garcianus, F. longifolius, new combination, F. nikitai, F. planifrons, new combination, F. poeyi, F.quilleri, F. sextus, new combination, and F. testudineus, new combination. Larvae belonging to the genus include species with consistent mouthpart morphology but variable with respect to development of a cephalic frontal keel and subapical tarsal claw setae. Caribaetis, originally considered a Cuban subgenus of Baetis, is shown to be a synonym of Fallceon. Baetis sonora is shown to be a synonym of Fallceon quilleri. Fallceonfortipalpus is described from the egg and larval stages. Larvae of F. longifolius, F. planifrons, and F. quilleri are redescribed, and the egg of F. quilleri is described for the first time. Fallceon longifolius is reported from continental North America (Mexico) for the first time. A key to the known larvae of Fallceon is provided. When originally described by Waltz and McCafferty (1987), the genus Fallceon included F. quilleri (Dodds) (type species) from Colorado (USA), F. eatoni (Kimmins) from Sonora (Mexico), F. buenoi (Allen) from San Luis Potosi (Mexico), and F. byblis (Allen and Murvosh) from Baja California Norte (Mexico). Later, McCafferty and Waltz (1990) added F. garcianus (Traver) from Puerto Rico and F. poeyi (Eaton) from Cuba, and synonymized F. buenoi, F. byblis, and F. eatoni with F. quilleri. All of the above species had been previously included in the genus Baetis Leach. McCaf ferty et al. (1992), in their study of the biogeography of the Panamerican mayfly genera, showed that the historical affinities of Fallceon were Neotropical. Kluge (1992a, b) described an additional five species from Cuba under the genus Baetis that have proven to be Fallceon (see below). More recently, McCafferty and Lugo Ortiz (1994) studied the syntypes ofF. poeyi, and reconfirmed McCafferty and Waltz's (1 990) placement of this species under Fallceon. In addition, McCafferty and Lugo Ortiz (1994) showed that Cuban material identified by Kluge (1992b) as F. poeyi was actually a distinct new species, F. nikitai McCafferty and Lugo-Ortiz, and they reinstated F. eatoni as a valid species. In the present study, we provide new information applicable to Fallceon resulting from our study of new collections of larvae from Central America, the Greater Antilles, Mexico, and the United States. Although not a comprehensive revision of Fallceon, we do include here a discussion of the genus, the description of a new species, and larval redescriptions of certain species, and synoptic discussions of all species known as larvae. In addition, we provide a first key to species based on larvae. Institutions housing the material examined in this study and their abbreviations are This content downloaded from 157.55. 39.231 on Thu, 06 Oct 2016 04:45:29 UTC All use subject to http://about.jstor. org/terms 1994 TAXONOMY OF FALLCEON 461 as follows: California Academy of Sciences, San Francisco (CAS); Colorado State University, Fort Collins (CSU); Cornell University, Ithaca, New York (CU); Florida AM Illinois Natural History Survey, Champaign (INHS); Instituto de Ecologia, A. C. , Veracruz, Mexico (IEAC); and the Purdue Entomological Research Collection, West Lafayette, Indiana (PERC).