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Telopathes gen. nov. MacIsaac & Best, 2013 Diagnosis. Observed attached to the side of a vertical cliff by a large, flat, adhesive, circular base. Corallum sparsely branched to the second order, branching not restricted to one plane, with branches directed distally. Stem and branches pinnulate. All pinnules simple, directed distally at an angle from the axis of the branch, in two anterolateral rows, arranged in either subopposite or alternate order. Pinnules long, maximum size estimated at up to 30 cm, the longest found on the stem and primary branches, with pinnules decreasing notably in length at branch tips. Spines are simple, conical, smooth, and compressed laterally. Polyps are elongate and arranged uniserially on branches and pinnules, and are comprised of three distinct sections separated by deep involutions. Preserved polyps range from 4.0– 7.1 mm in transverse diameter. Type species. Telopathes magna MacIsaac & Best 2013 herein designated. Remarks. The genus is distinguished by the sparsely branched corallum, with branching not restricted to one plane (Fig. 2 A–F), the long, simple, anterolateral pinnules in two rows (Fig. 3 A–F), largely pinnulated stem, and adhesive base. Although only one fragment of the holotype colony was collected, diagnostic features observed between the fragment and in situ video and photographs define the monospecific genus Telopathes gen. nov. as new for the family Schizopathidae. It is possible that additional features diagnostic for the species are not reported because the entire colony was not collected. Species descriptions of antipatharians based solely on fragments exist, including the recent example of Dendrobathypathes boutillieri. In the past some such descriptions have proven incomplete and historically contributed to taxonomic confusion (Molodtsova 2006), but the description of Telopathes also includes information on the entire colony from in situ video and photographs, and includes several paratypes. The molecular data presented should also mitigate any issues surrounding the identification of additional specimens of T. magna, which may include unobserved or otherwise novel morphological features. The description and occurrence of T. magna brings the number of new genera added to family Schizopathidae over the past decade to three (Opresko 2002, 2005) and the number of nominal species of Antipatharia reported to occur off eastern Canada to at least 12. Species assigned to Telopathes . One species: T. magna MacIsaac & Best, 2013 Etymology. Derived from the Latin telum (dart), in reference to the shaft and flights of a dart and the general shape of the corallum, and the commonly used suffix pathes. Distribution. One species of this genus is known, from the western North Atlantic. Telopathes magna new species (Figs. 2–7) Holotype. NSMC 17671, Western North Atlantic, Nova Scotia continental slope, near the mouth of the Laurentian Channel, 44.428098 N, 57.173328 W, depth 1073 m. Video, high resolution photographs, and a 16.7 cm fragment collected by ROPOS, Dive 1063, aboard CCGS Hudson, mission 2007 -025. Fragment initially fixed in formaldehyde, transferred to ethanol; subsamples preserved in ethanol for molecular analysis. Holotype with subsamples archived in the Nova Scotia Museum Collection, Halifax, Nova Scotia, Canada. Other material. Paratype YPM- 35975: R/V Delaware II, cruise DE 02-06, July 16 –August 2, 2002, New England Seamounts (NES), Bear Seamount (Smnt), 39.88333 N, 67.46666 W, 1195–1402 m (one specimen trawled). Paratype BAL 103 - 1: R/V Ronald H. Brown and IFE ROVs Argus and Hercules, cruise RB 04-04, May 9 – 24, 2004, NES, Balanus Smnt, 39.35608 N, 65.35958 W, 1865 m (one specimen). Paratype YPM- 35498: cruise RB04-04, NES, Retriever Smnt, 39.80965 N, 66.24922 W, 1983 m (one specimen). Paratype MIL 112 - 1: R/V Ronald H. Brown and IFE ROVs Argus and Hercules, cruise RB 05-03, August 10 – September 3, 2005, Corner Rise Seamounts, Caloosahatchee Smnt, Milne-Edwards Peak, 34.8123 N, 50.5038 W, 1310 m (one specimen, small/juvenile). Paratype REH 103 - 1: cruise RB05-03, NES, Rehoboth Smnt, 37.46066 N, 59.95133 W, 1909 m (one specimen). Diagnosis. Stem largely pinnulate, colony sparsely branched to the second order, primary branches not restricted to one plane, branches directed distally and curving outward. Pinnules arranged in two anterolateral rows, in alternate or subopposite arrangement, but occasionally with two pinnules in a row on one side. Internal angle of approximately 70 º between opposite pairs of pinnules on the primary branch collected. Pinnules directed distally at an angle from the axis of the branch. Pinnules long, up to approximately 30 cm on the stem, 18 cm on primary branches, and 9 cm on secondary branches, decreasing notably in length near branch tips. Primary branch has an average 2.8 pinnules per cm, spaced 0.8 –1.0 cm apart in each row. Secondary branches have 2–3 pinnules per cm, spaced 0.7–0.8 cm apart in each row. Proximal sections on both secondary branches without pinnules, or very sparsely pinnulated. Primary branch sparsely populated with polyps, with some spaces between pinnules devoid of polyps. In contrast, secondary branches have 1–2 polyps between pinnules. Polyps arranged uniserially, with densities of 0–1 polyps per cm on the primary branches, and 1–2 polyps per cm on the secondary branches and pinnules. Polyps are 4.0– 7.1 mm in transverse diameter on the fragment. Skeletal spines simple, smooth, compressed laterally, conical or sometimes curved, in which case they are generally directed proximally (Fig. 5 A– C, Fig. 7 A–C). Spines are 0.019–0.068 mm tall; 0.012–0.041 mm in transverse diameter at their base. Spines on the polypar sides of the pinnules are slightly larger than on the abpolypar side: 0.029–0.068 mm and 0.019–0.061 mm, respectively. This characteristic is difficult to observe with a dissecting scope, though the discrepancy is more pronounced in the juvenile specimen (Fig. 7 C). Number of spines in each row 2–6 per mm. Description of the holotype. Telopathes magna spec. nov. was observed attached to a vertical cliff with a prominent stem and large, circular basal plate approaching 30 cm in diameter (Fig. 2 A–F). Orientation of the colony horizontal in the water, at a right angle to the vertical substrate. The type specimen is described from photos, video, and a fragment of one primary branch 16.7 cm in length, 36.0 cm wide. Fragment bearing two secondary branches 18.6 and 20.0 cm in length, 18.9 and 17.0 cm in width respectively (Fig. 3 A–B). Total colony size large, estimated at over 80 cm tall, greatest width approximately 85 cm. Stem mostly pinnulate, proximal few centimetres sparsely pinnulated or lacking pinnules. Stem thick near base, with an estimated basal stem diameter approaching 1 cm. Corallum branched to the second order, the longest branch approximately 39 cm long. Branches not restricted to one plane, directed distally. Pinnules long, 9–30 cm, shortening near branch tips, in two anterolateral rows, forming an acute angle between opposite pairs (Fig. 3 E). Pinnules directed distally. Branches more rigid while pinnules more flexible. One abnormally recurved pinnule observed in proximity to a deformed or bent secondary branch (Fig. 3 C–D), possibly indicating earlier damage to the colony. Living colony with bright orange polyps, tissue covering stem and branches more yellowish (Fig. 2 & 3). After preservation polyps brown, tissue lighter on the stems and branches. Tentacles long in living colony, up to an estimated 1 cm or more (Fig. 3 F), shorter after preservation. Polyps after preservation up to 7.1 mm in transverse diameter (Fig. 4 A–C). Skeletal spine morphology as described above, seven to nine longitudinal rows visible on pinnules in lateral view (Fig. 5 A–B), six to seven rows on branches. Rows on pinnules separated by 0.047–0.157 mm, spines within each row an average of 0.395 mm apart, not always uniformly spaced; occasionally sections in rows lack spines completely (indicated in Fig. 5 A), particularly in the distal sections. Occasionally spines are paired (Fig. 5 C)—a characteristic observed only on the pinnules, not on primary branches examined. Description of the Paratypes. Specimens from New England Seamounts similar morphologically to each other and holotype, but not identical, with branching to the first and second order in more than one plane (Fig. 6 A– D). All paratypes with relatively smaller basal plates compared to holotype, and basal plate not concentric on one large colony, indicating some intraspecific variation in this character, possibly due to the nature of the substrate on which the planula settles. Colony from Rehoboth Seamount (Fig. 6 D) appears to be the largest observed based on lasers on in-situ photographs, with conservative estimates of maximum height and width of approximately 133 cm and 150 cm respectively. The largest pinnules were estimated to be slightly smaller than the holotype at 24 cm in length. Colony branching was more dense than in smaller and probably younger colonies. Skeletal spines on pinnules collected from paratypes similar but not identical to holotype, are small and conical, with a size ranging from 0.019 mm (Rehoboth Seamount specimen) to 0.065 mm (Retriever Seamount specimen); smaller than those observed in the holotype. Distribution of spine sizes measured reveals a typically small difference between polypar and abpolypar sides. FIGURE 4. Polyps of Telopathes magna. (A–C) Arrangement of polyps along a pinnule; M = Mouth, ST = Sagittal tentacle, LT = Lateral tentacle. (A) Oral view. (B) Side view; P 1 & P 2 = individual polyps. (C) Close-up view of a typical polyp. (D) Arrangement of polyps along the primary branch. Scale 0.5 cm. The juvenile/small colony from Milne-Edwards Peak (Fig. 6 B–C) measured 27 cm in length, 13 cm in width, with the largest pinnule 7 cm in length. This specimen superficially resembles the genus Bathypathes. Primary pinnules large and simple, but are deflected anteriorly from the lateral plane. With one primary branch off main stem, this is distinguished by limited pinnulation and/or secondary branching. Skeletal spines on pinnules similar but not identical to holotype, small and conical, with a size ranging from 0.037–0.056 mm (Fig. 7 C). Distribution of spine sizes distinctly different on the juvenile colony, with notably larger spines on the polypar side, a range of 0.048–0.062 mm, and smaller spines on the abpolypar side, 0.037–0.047 mm with a mean of 0.048 mm (Fig. 7 C). All paratypes indistinguishable genetically from each other and the holotype. Comparisons. Telopathes appears morphologically most similar to the monopodial genus Bathypathes, especially smaller colonies, both possessing very long, simple pinnules in two rows, arranged in alternate or subopposite order. The polyps of both Telopathes and Bathypathes are large, the only two genera of Schizopathidae with polyps that may be in excess of 6 mm (Table 2). Differences include the branched corallum of Telopathes, though this branching may be slight, and the pinnules deflected from the lateral, observable even in the small colony (Fig 7 B–C). Schizopathes and Abyssopathes also possess large polyps and long, simple pinnules in two rows, but like Bathypathes, both are monopodial. In Schizopathes the pinnules are also lateral, not deflected, and the colony anchors in soft sediments, lacking a basal plate. Abyssopathes may have pinnules deflected from the lateral axis, like Telopathes, but also possesses the curious schizopathinid feature of one or more rows of anterior pinnules. Stauropathes is another large polyp genus, but the pinnules are short, and may be densely branched. The largest colony of Telopathes from Rehoboth Seamount was more densely branched than small and medium sized colonies observed, more similar to Stauropathes in this regard. It is possible that even larger/older colonies of Telopathes may be more densely branched, more closely resembling Stauropathes. All other genera of Schizopathidae belong to the subfamily Parantipathinae, with complex patterns of pinnulation (some combination of subpinnulation and/ or additional rows of pinnules beyond two), and small polyps typically less than 3 mm in diameter. Etymology. The specific name is derived from the Latin magnus (large), referring to the relatively large pinnules. Distribution. Known from the western North Atlantic, continental slope off Nova Scotia, New England Seamounts and Corner Rise Seamounts. At a depth of 1073 m on the continental slope to 1983 m on the seamounts (shallowest depth on seamounts 1195–1402 m). |
