Atlantic Flyingfishes of the Genus <I>Cypselurus</I>
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ATLANTIC FLYINGFISHES OF THE GENUS CYPSELURUS, WITH DESCRIPTIONS OF THE JUVENILES1 JON C. STAIGER Institu/e of Marine Science, University of Miami ABSTRACT The Atlantic species of the exocoetid genus Cypselurus are reviewed and six species recognized: Cypselurus coma/us, C. cyanopterus, C. exsiliens, C. furcatus, C. heterurus, and C. pinna/ibarba/us. A diagnosis and synonymy is presented for the genus, as well as dis- cussions of ontogeny and range. The splitting of Cypselurus and recogni- tion of the genus Cheilopogon by Parin (1961) is not accepted. Two keys to Atlantic species are presented; one for specimens under 100 mm standard length, the other for larger specimens. For each species distinctive characters, description, and synonymy are given, and ontogeny, range and reproductive biology are discussed. Particular attention is paid to the ontogenic changes in pectoral and pelvic fin coloration with regard to identification. The placement of C. luetkeni in the synonymy of C. heterurus and of C. lineatus in the synonymy of C. pinnatibarba/us is upheld. lNTRODUCTION AND ACKNOWLEDGMENTS The systematics of the flyingfishes (Exocoetidae) have been confused since the description of a second species in 1766. Though more than 60 names had been proposed for the Atlantic forms by 1935, investigators studying large series of specimens have recognized no more than 20 as valid. Bruun (1935: 5-8) listed the synonymy of the group and recognized 17 species. Breder (1938: 56) reduced this number to 16. Much of the difficulty encountered in describing exocoetids results from the presence of usually considerable growth changes, such that the adults of some species bear little resemblance to juveniles in color pattern and presence of mandibular barbels. Most early workers had so few specimens that no complete developmental series could be assembled, and many new species were named for the juvenile forms of existent species. Breder was the first to describe developmental series of many Atlantic species, but he did not have enough specimens to construct a key that would function for individuals of all sizes. This paper reviews in a comparative manner the Atlantic species of Cypselurus in the light of the large number of specimens at my disposal, describes in detail some of the ontogenic changes of each species, and pre- sents a key adequate to identify juvenile as well as adult specimens. IContribulion No. 639 from The Marine Laboratory, lnstitute of Marine Science University of Mia,mi, Florida, This paper is a modification and enlargement of a thesi~ submitted In partial fulfillment of the degree of Master of Arts, Boston University, Boston, Massa- chusetts. 1965] Staiger: Atlantic Flyingfishes 673 This work was undertaken at Boston University at the suggestion of Dr. Robert H. Gibbs, Jr., and I am very grateful to him for his continuing helpful criticism and valuable suggestions. The original study was enlarged and the manuscript considerably revised under the supervision of Dr. C. Richard Robins of the Marine Laboratory, Institute of Marine Science, University of Miami, and I express my gratitude to him for his patience, advice, and criticism. For the loan of specimens I am indebted to Mr. Jack W. Gehringer of the Bureau of Commercial Fisheries, Biological Labora- tory, Brunswick, Georgia, Dr. Giles W. Mead of the Museum of Compara- tive Zoology, Harvard University, and Dr. Carter R. Gilbert of the University of Florida. Specimens at the National Museum were examined through the courtesy of Dr. Leonard P. Schultz. Dr. Thomas W. McKenney advised me in the preparation of the fin dia- grams and Mr. William P. Davis assisted invaluably in the preparation of the photographs. This study was supported in part by a grant-in-aid from the National Science Foundation (NSF-G-19324). MATERIALS Specimens examined were from the following sources: Boston University (BU) (these specimens are now at the United States National Museum); Museum of Comparative Zoology, Harvard University (MCZ); Marine Laboratory, University of Miami (UMML); Bureau of Commercial Fisher- ies Biological Laboratory, Brunswick, Georgia (BLBG); United States National Museum (USNM); University of Florida (UP). METHODS All measurements were taken with dial calipers. The lengths were read to 0.1 mm and are presented as percentages of standard length. The methods of measurement are taken from Bruun (1935: 13), except for new ones used here. I. Standard length. Tip of snout to end of hypural plate. 2. Dorsal and anal-fin hei!lhts. Insertion of longest ray to its tip. 3. Pectoral and pelvic-fin lengths. Insertion of first ray to tip of longest ray. 4. Prepectorallength. Tip of snout to insertion of pectoral fin. 5. Interorbital width. Least clistance across the ossified portion of the or- bits, not including any soft parts. 6. Barbel length. Tip of barbel to point at which the posterior edge of the barbel meets the skin of the lower jaw. 7. Fir~t pectoral ray length. Tip of first well developed pectoral ray to its origin. 8. Di~tance between first and second pectoral rays. Measured at the distal end of the first ray. 9. Distance between the second and third pectoral rays. Measured along the same line as the measurement for the first-second ray distance. 674 Bulletin of Marine Science [15(3) Meristic characters were examined with a binocular dissecting micro- scope. Counts were made according to Hubbs & Lagler (1958: 19-24). 1. Dorsal and anal-fin rays. The last ray is frequently bifurcate to its base, but was always counted as one ray. All elements were counted. 2. Pectoral rays. The first pectoral ray is small and difficult to see and is omitted in counts, conforming with the practice of previous workers. 3. Vertebrae. Counts were taken from specimens stained with alizarin red-S and cleared in glycerin, or from X-rays. The hypural plate was counted as one vertebra. Caudal and precaudal vertebrae were not counted sepa- rately. 4. Predorsal scales. Counted along the mid-dorsal line from end of occiput to dorsal fin origin. 5. Postdorsal lateral scales. Counted mid-laterally from the first row of scales behind the dorsal origin to the hypural plate. 6. Scales above the lateral line. Counted along the diagonal scale row from beside the first dorsal ray to, but not including, the lateral line scale. Palatine teeth were exposed by cutting through the angle of the jaw, and were counted as present only when they could be seen as well as palpated. Strength of palatine dentition was based on the abundance of teeth. Genus Cypselurus Swainson, 1839 Cypsilurus Swainson, 1839: 187, 296 (original description; illustration; type- species Exocoetus appendiculatus Wood, 1825 = E. comatus Mitchill, 1815; misprint for Cypselurus according to Opinion no. 26 of the Inter- national Commission on Zoological Nomenclature).-Bruun, 1935: 11-13 (description; illustration; key)-Smith, 1950: 125 (description; illustration; key). Cypselurus. Lowe, 1840: 38 (description).-Agassiz, 1846: (correction of Cypsilurus Swainson, 1839 and Cyprilurus DeKay, 1842; fide Breder, 1938: 38).-Jordan & Gilbert, 1882: 380 (description).-Breder, 1928: 23 (synonymy) .-Jordan, Evermann, & Clark, 1930: 201 (listed).- Parr, 1930: 20-25 (description; illustration).-Fowler, 1936: 423, 1240 (description; key; synonymy).-Breder, 1938: 38 (description; illustra- tion; key; synonymy).-Hubbs & Kampa, 1946: 205 (description; key). -Lozano Rey, 1947: 619 (description; illustration; key).-Parin, 1960: 16-19 (description; key) .-Smith, 1961: 125 (description; illustration; key).-Parin, 1961: 163-165 (description; illustration). Cheilopogon Lowe, 1840: 38 (original description; type-species Cypselurus pulchellus Lowe, 1840 = Cypselurus pinnatibarbatus (Bennett, 1831); Madeira) .-Hubbs & Kampa, 1946: 207 (description as subgenus; key; illustration) .-Parin, 1961: 167 (description; key; illustration). Cyprilurus. DeKay, 1842: 231 (misprint for Cypselurus). Ptenichthys MUller, 1843: 312 (original description; type-species Exocoetus !urcatus Mitchill, 1815) .-Parin, 1961: 173-174 (description; key; illustra- tion) . Exonautes Jordan & Evermann, 1896a: 322 (original description; type- species Exocoetus exsiliens (Linnaeus, 1771) ). 1965] Staiger: Atlantic Flyingfishes 675 Ptenonotus Ogilby, 1908: 13 (original description; type-species Exocoetus cirl'iger Peters, 1877).-Ogilby, 1914: 13 (verbatim reprint of 1908 above). Eucypsilurus Bruun, 1935: 84 (original description; type-species Cypsilurus heterurus (Rafinesque, 1810)). Poecilocypsilurus Bruun, 1935: 84 (original description; type-species Cypsil- urus callopterus (GUnther, 1866)). Procypsilurus Bruun, 1935: 84 (original description; type-species Cypsilurus exsiliens (Linnaeus, 1771)). Maculocoetus Whitley & Colefax, 1938: 287 (original description; type- species M aculocoetus suttoni Whitely & Colefax, 1938; Gilbert Islands). -Parin, 1961: 168-170 (description; illustration; key). Abeichthys Parin, 1961: 171-173 (original description; type-species Exocoe- tus agoo (Temminck & Schlegel); key; illustration). Poecilocypselurus. Parin, 1961: 165-167 (description; key; illustration). Procypselurus. Parin, 1961: 168 (description; key; illustration). Diagnosis.-Pectoral fins greater than 45 per cent of standard length (except in very small juveniles, shorter than about 15 mm); reaching at least to the dorsal fin midpoint (except in very small juveniles). Pelvic fins longer than 26 per cent of standard length; reaching at least to anal fin midpoint. Anal fin with shorter base than dorsal fin; beginning well