2009 NORTHEASTERN NATURALIST 16(3):409–414 The First Records of Neocyema (Teleostei: Saccopharyngiformes) in the Western North Atlantic with Comments on its Relationship to Leptocephalus holti Schmidt 1909 Shannon C. DeVaney1,2,*, Karsten E. Hartel3, and Daphne E. Themelis4 Abstract - Two new specimens of the rare deep sea eel genus Neocyema were collected in the western North Atlantic in June 2006 and September 2008. Previously the genus was known only from the two type specimens, collected in the South Atlantic in 1971. External morphology and osteology indicate that the new specimens probably belong to the described species Neocyema erythrosoma. Their capture in the North Atlantic provides support for the hypothesis that Neocyema is the adult form of the enigmatic larva Leptocephalus holti. Introduction A bright orange leptocephalus-like eel (Fig. 1) was collected during a NOAA National Marine Fisheries Service deepwater biodiversity survey in the vicinity of Bear Seamount at 39°51'N, 67°02'W on 17 June 2006. Two years later, another small orange eel (Fig. 2) was collected during a Canadian Department of Fisheries and Oceans research cruise to the Gully Marine Protected Area at 43°45'N, 58°48'W on 5 September 2008. These two specimens (MCZ [Museum of Comparative Zoology, Harvard University] 165900, 91 mm SL; ARC [Atlantic Reference Centre, Huntsman Marine Science Center, St. Andrews, NB, Canada] 28117, 88 mm SL) are very similar to Neocyema erythrosoma Castle 1977 (Fig. 3), which was described and previously known from two specimens collected in the central and eastern South Atlantic in 1971. The current specimens represent the third and fourth confirmed records of the genus Neocyema, and the first records from the western North Atlantic. The family Cyematidae (Actinopterygii: Saccopharyngiformes) is composed of two species described from adult material: Cyema atrum Günther 1878, and Neocyema erythrosoma. Both Cyema and Neocyema adults are short-bodied and laterally compressed, with long, delicate jaws, small teeth, and small eyes. Cyematids were once placed in the family Nemichthyidae (snipe eels) leading to their common name, the “bobtail snipe eels.” However, several authors (Bertin 1937, Raju 1974, Robins 1989) have pointed out that cyematids are morphologically closest to saccopharyngiform (gulper) eels. 1Department of Ecology and Evolutionary Biology and Biodiversity Institute, Natural History Museum, University of Kansas, 1345 Jayhawk Boulevard, Lawrence, KS 66045. 2Current Address - Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007. 3Museum of Comparative Zoology, Harvard University, 26 Oxford Street, Cambridge, MA 02138. 4Department of Biology, Mount Saint Vincent University, Halifax, NS, B3M 2J6, Canada.*Corresponding author - sdevaney@nhm.org. 410 Northeastern Naturalist Vol. 16, No. 3 The genus Neocyema is particularly notable for its vibrant red-orange color and apparently paedomorphic condition. In the species description, Castle (1977) indicated that the holotype and paratype were originally thought to be leptocephali or metamorphic specimens, until his further analysis revealed them to be adults. Similarly, when the first of the new specimens (MCZ 165900) was originally collected, the general first impression of the scientific party (which included S.C. DeVaney and K.E. Hartel) before it was identified as a Neocyema, was that it was a transforming larva. Like Castle (1977), we note small eggs in long, paired ovaries in our specimens. The new specimens come from a relatively well-sampled region of deep ocean. Recent work (Hartel et al. 2008, Moore et al. 2003) documents 631 fish species known to occur below 200 m in an area off greater New England. These records are the result of thousands of trawls made principally by the Woods Hole Oceanographic Institution and by the National Marine Fisheries Service. The Canadian Department of Fisheries and Oceans has made several hundred midwater tows over the continental slope near the Scotian Shelf, capturing more than 260 mesopelagic species (D.C. Themelis, unpubl. data). The fact that these specimens are the first records of Neocyema in the western North Atlantic underscores the rarity of the genus. Figure 3. Holotype of Neocyema erythrosoma, reproduced from Castle (1977). Figure 1. New specimen of Neocyema (MCZ 165900). Stomach exposed due to net damage to ventral body wall. Figure 2. New specimen of Neocyema (ARC 28117). 2009 S.C. DeVaney, K.E. Hartel, and D.E. Themelis 411 Materials and Methods The first new specimen of Neocyema (MCZ 165900) was collected by the NOAA ship R/V Delaware II in an International Young Gadoid Pelagic Trawl (IYGPT) midwater trawl fished open to 2284 m over an average bottom depth of 3424 m. The second new specimen (ARC 28117) was collected by CCGS Wilfred Templeman in an IYGPT midwater trawl fished open to 1620 m over an average bottom depth of 2500 m. Both specimens were photographed and fixed in formalin shortly after capture. In order to preserve the integrity of these rare specimens, they were not cleared and stained; instead, osteology was examined via X-ray imaging. Digital images and X-rays of the intact holotype and the cleared and stained paratype of Neocyema erythrosoma, as well as specimens and images of Cyema atrum, were examined for comparison to the new specimens. Specimens Examined: were Cyema atrum - MCZ 47843, MCZ 52122, MCZ 60589, MCZ 60592, MCZ 100870, MCZ 144806, MCZ 148419, MCZ 165935. Neocyema sp. - MCZ 165900, ARC 28117. Neocyema erythrosoma - ISH (Institut für Seefischerei Hamburg collection, now at Universität Hamburg ) 1194-1971 (holotype), ISH 956-1971 (paratype; cleared). Discussion Identification of the specimens Castle (1977) provided a thorough diagnosis of Neocyema erythrosoma (Table 1). Like the type specimens, the new specimens were bright red-orange at the time of capture, fading to white in alcohol. Myomeres are easily visible through the transparent skin. The new specimens also have the same extreme skeletal reductions known from the type specimens. In these fishes, both the opercular series and the pectoral girdle are absent, and only a single branchial Table 1. Neocyema data from Castle (1977), ARC 28117, and MCZ 165900. Leptocephalus holti data from Smith and Miller (1996). Neocyema Leptocephalus holti Holotype Paratype MCZ ARC Species 1 Species 2 Species 3 Total myomeres 108 101 105 105 99–117 108–130 104–115 Pre-vent myomeres 50 47 50 46 45–65 65–75 54–57 Standard length (mm) 140 160 91 88 Branchial arch 1 1 1 1 Dorsal rays 111 114 115 115 Anal rays 75 85 79 77 %SL Head 16.2 19.4 21 20.2 Snout 5.8 4.4 8.1 8.2 Eye 0.4 0.5 0.4 1.3 Mouth 9.3 7.5 13 13.5 Pectoral 2.9 1.9 Damaged 2.9 Predorsal 64.9 66.5 64.3 61.4 Snout–Anus 64.2 63.9 62.7 63.1 P1 depth 6.1 6.6 10.1 8.4 Anus depth 8.0 10.8 11.3 12.4 412 Northeastern Naturalist Vol. 16, No. 3 arch is present. The long upper jaws are formed by the maxillae (interpreted as the pterygoid by Robins [1989]), and the lower jaws by the dentaries; neither premaxillae nor articular bones are present. Among the differences between the new specimens and the types are a relatively longer head, snout, and mouth; however, these and other differences may be because the new specimens are 35–45% smaller than Castle's specimens. The eyes of the Canadian specimen seem more oval than the other specimens and are angled at about 45° relative to the upper jaw. The longest measurement of the eye in this specimen is 0.9% SL, and the shortest measurement is 0.5% SL. Leptocephalus holti connection Schmidt (1909) described a distinctive leptocephalus from the northeastern Atlantic as Leptocephalus holti, but he did not link it to any known adult. Sixty-five years later, Raju (1974) described a similar larva from the Pacific, noting its similarity to, yet distinctness from the known larva of Cyema atrum. Both L. holti and the larva of C. atrum have the v-shaped myomeres, elongate suspensorium, and looped intestines typical of saccopharygiform leptocephali; however, L. holti and the C. atrum larva share several characters that distinguish them from other saccopharyngiform larvae, including an elongate snout, only 2–4 intestinal loops, large eyes, and distinctive lateral pigment patterns (Raju 1974, Smith and Miller 1996). Given the morphological evidence, Raju (1974) was "compelled to relate [L. holti] to an unknown species of the family Cyemidae." Four years later, when Castle (1977) described the second cyematid species, Neocyema erythrosoma, he discussed the possibility that it might be the adult form of L. holti. Smith (1989) expressed the same idea, but both authors considered the link inconclusive, largely because adult Neocyema specimens lack the lateral pigment seen in L. holti. Furthermore, the known distribution of Castle's Neocyema specimens was from 37°S to 39°S in the Atlantic, which was over 5000 km from the closest known L. holti in the Pacific and northern Atlantic. Smith and Miller (1996) reviewed new material of Leptocephalus holti, adding 47 additional specimens. They concluded that there were three species or species groups within the material and described each in some detail. The new specimens revealed that most Atlantic L. holti lack lateral pigment, thereby removing one of the obstacles to linking this leptocephalus to Neocyema. The other major obstacle can be surmounted based on the Neocyema specimens presented herein, as they were collected close to the known localities of all three forms of L. holti (Fig. 4). There is now little doubt that Leptocephalus holti are the larvae of Neocyema. However, the question that remains is which of the three larval forms can be linked to any of the four adult specimens of Neocyema. Smith and Miller's species 2, which includes Schmidt's (1909) holotype, seems to be the most highly pigmented form, and therefore, the least likely. Smith and Miller’s L. holti species 1 seems to be the closest to the known Neocyema specimens based on myomeres (Table 1); however, myomere counts overlap, and we cannot be sure which of the species currently included under the name L. holti should be linked to known adults of Neocyema. 2009 S.C. DeVaney, K.E. Hartel, and D.E. Themelis 413 Summary It is clear that the new specimens are Neocyema, making them the third and fourth known records of the genus and the first from the North Atlantic. A possible fifth specimen is discussed by Mead (1964), who noted "the capture of a leptocephalus or larval stage of a deep sea eel, which is bright orange-red in color" during a 1964 Indian Ocean expedition. The description strongly resembles a Neocyema; however, no catalog number for the specimen is given, and to date the specimen has not been found. Given the small number of Neocyema specimens and the relatively minor differences between the new specimens and the types of N. erythrosoma, we do not presently consider the new specimen to be a new species of Neocyema. However, as Smith and Miller (1996) identified three species or species groups of L. holti, which we now assert should be recognized as a larval form of Neocyema, we might expect that there are at least two additional species Figure 4. Known localities of Neocyema and Leptocephalus holti in the Atlantic: type specimens of N. erythrosoma (triangles), Neocyema new records (stars), and Leptocephalus holti (circles). Localities based on ARC and MCZ specimen data and literature. 414 Northeastern Naturalist Vol. 16, No. 3 of Neocyema waiting to be described. Finally, it should be noted that, if we are correct in linking Neocyema with L. holti, the species Neocyema erythrosoma Castle 1977 may more correctly be called Neocyema holti (Schmidt 1909), depending on which of the species of L. holti is definitively associated with this adult. Acknowledgments We wish to thank James E. Craddock, David G. Smith, C. Richard Robins, and two anonymous reviewers for useful comments on the manuscript. Ralf Thiel and Irina Eidus generously provided digital images and X-rays of the type specimens of Neocyema erythrosoma from the fish collection at Universität Hamburg. Andrew Williston (MCZ) produced Figure 1 and 4; Andrew Cogswell (BIO) produced Figure 2. This work was supported in part by a grant from the W.M. Keck Foundation to the program in Molecular Systematics and Evolution at the Natural History Museum of Los Angeles County. Finally, we thank Chief Scientists Michael Vecchione and Trevor Kenchington, the scientific parties, and the officers and crews of the R/V Delaware II during the 2006 Deepwater Biodiversity Survey and the CCGS Wilfred Templeman during the 2008 Survey of the Gully MPA. Literature Cited Bertin, L. 1937. Les poissons abyssaux du genre Cyema Günther (anatomie, embryologie, bionomie). Dana Report 10:1–30. Castle, P.H.J. 1977. A new genus and species of bobtail eel (Anguilliformes, Cyemidae) from the South Atlantic. Archiv für Fischereiwissenschaft 28(2/3):69–76. Günther, A. 1878. Preliminary notices of deep-sea fishes collected during the voyage of the H.M.S. “Challenger.” Annals and Magazine of Natural History 5(2):17–28, 179–187, 248–251. Hartel, K.E., C.P. Kenaley, J.K. Galbraith, and T.T. Sutton. 2008. Additional records of deep-sea fishes from off greater New England. Northeastern Naturalist 15(3):317–334. Mead, G.W. 1964. Narrative report: Anton Bruun Cruise 6. US Program in Biology. 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