Yıldız et al. Helgol Mar Res (2016) 70:24 DOI 10.1186/s10152-016-0476-5 Helgoland Marine Research ORIGINAL ARTICLE Open Access A new species of Cephalorhyncha Adrianov, 1999 (Kinorhyncha: Cyclorhagida) from the Aegean Coast of Turkey Nuran Özlem Yıldız1*, Martin Vinther Sørensen2 and Süphan Karaytuğ3 Abstract Kinorhynchs are marine, microscopic ecdysozoan animals that are found throughout the world’s ocean. Cephalorhyn- cha flosculosa sp. nov. is described from the Aegean Coast of Turkey. Samples were collected from intertidal zones at two localities. The new species is distinguished from its congeners by having flosculi in midventral positions on segment 3–8, and by differences in its general spine and sensory spot positions. Until now, species of Cephalorhyn- cha were only known from the Pacific Ocean, hence, this record of the genus at the Aegean Sea not only expands its geographic distribution to Turkey, but is likely to expand it throughout the Mediterranean Sea and much of south- ern Europe. The new species of Cephalorhyncha represents the fifth kinorhynch species recorded from Turkey, and increases also the number of known Cephalorhyncha species to four. Keywords: Kinorhynchs, Flosculi, Meiofauna, Mediterranean Sea, Taxonomy Background sternal plates, i.e., fissures of the tergosternal junctions The phylum Kinorhyncha is classified within the inver- are fully developed whereas the midsternal junction is tebrate animals. They are microscopic marine worms incomplete. Segments 3–10 consist of one tergal and two generally not longer than 1 mm. Kinorhynchs live sternal plates [3, 13, 14]. throughout the world’s ocean, from intertidal areas to Effective management and conservation of biodiver- 8000 m in depth. They are most common in subtidal sity and ecosystems depends largely on the taxonomic muddy sediments, but some have been found in algal determination of species composition. Unfortunately, holdfasts, sponges, or other invertebrates. [1–3]. The insufficient taxonomic information intercepts our abil- phylum currently comprises about 239 species distrib- ity to make informed decisions about conservation and uted across 29 genera [4–11]. Cephalorhyncha is a small sustainable management of biodiversity and ecosystems. genus accommodating only three species. The genus Turkey has numerous sandy beaches distributed along (type species Cephalorhyncha asiatica [12] was proposed its coastline, but the marine meiofauna has been poorly by Adrianov [13]. Later, Neuhaus and Blasche [14] reas- explored despite the fact that the country has a vast signed the Californian species Echinoderes nybakkeni coastline of about 8300 km. From a taxonomic perspec- Higgins, 1986 [15] to Cephalorhyncha. The third species, tive, mostly the Copepoda have been studied to a large C. liticola Sørensen, 2008 [16] was described from Hawaii extent [17, 18]. Oppositely, the marine and meiobenthic by Sørensen [16]. Species of Cephalorhyncha are charac- Kinorhyncha have been very poorly explored. Băcescu terized by possessing a sternal plate of segment 2 that is [19] reported the first kinorhynch species, Pycnophyes only incompletely differentiated into one tergal and two communis Zelinka, 1908, from the Black Sea. Later, Sön- mez et al. [20] reported Echinoderes gerardi Higgins, 1978 and a species resembling Echinoderes bispinosus *Correspondence: [email protected] Higgins, 1982 from the Aegean coast of Turkey, and Ürk- 1 Silifke Vocational School Aquaculture Program, Mersin University, 33940 Mersin, Turkey mez et al. [21] found Echinoderes dujardinii Claparède, Full list of author information is available at the end of the article 1863 from subtidal sediments of Sinop Bay, Black Sea. In © The Authors 2016. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Yıldız et al. Helgol Mar Res (2016) 70:24 Page 2 of 13 the present paper, a new species of Cephalorhyncha col- and examined with a JEOL JSM-6335F Field emission lected at two intertidal localities from the Aegean Coast scanning electron microscope. of Turkey is described. Terminology follows Sørensen and Pardos [3] and Neu- haus [2]. Specimens used for morphological comparison Methods include type material of Cephalorhyncha liticola (Natu- Samples were collected from two intertidal localities ral History Museum of Denmark, Cat. Nos. KIN-205 to (Fig. 1): the north coast of Kara Island, ca. 5 km south- KIN-207) and topotype specimens of C. asiatica, kept in east of Bodrum on the Turkish mainland (36°59′08″N, the personal collection of MVS. 27°27′13″E), and at Çalış on the beach of Fethiye (36°39′33″N, 29°06′35″E) using the Karaman–Chappius Results method [22]. This method consists of a funnel-shaped Systematics excavation into the sediment down to the groundwater Phylum Kinorhyncha Dujardin, 1851 [23] level, allowing sea water to fill the bottom of the pit, and Class Cyclorhagida Zelinka, 1928 then collecting that water with a suitable cup and filtering Order Echinorhagata Sørensen et al., 2015 it through plankton net. The filtered samples were fixed in FamilyEchinoderidae Zelinka, 1894 [24] 70% alcohol and kinorhynch specimens picked up using Genus Cephalorhyncha Adrianov, 1999 an Olympus SZ-16 stereomicroscope. Specimens for light microscopic examination were dehydrated through Cephalorhyncha flosculosa sp. nov a graded glycerin series, and mounted in Fluoromount- Material examined G between two cover slips, and attached to a plastic H–S Holotype, adult female, collected on May 16, 2011 from slide mount which enables from viewing from both sides. intertidal sand at Çalış (Fig. 1), Aegean Coast of Turkey The specimens were examined with an Olympus BX51 (36°39′33″N, 29°06′35″E) by Dr. Serdar Sönmez and Dr. compound microscope equipped with DIC optics. Pho- Serdar Sak, mounted in Fluoromount-G and deposited tos were taken with an Olympus DP27 camera, and line at the Natural History Museum of Denmark under cata- art illustrations were made in Adobe Illustrator CS6. logue numbers ZMUC KIN-1005. Paratypes include one Specimens for scanning electron microscopy were dehy- female and two males collected on the same date and drated through a graded alcohol-acetone series, and were locality as the holotype, mounted in Fluoromount-G and subsequently critical point dried, mounted on aluminium deposited at the Natural History Museum of Denmark stubs, sputter coated with a platinum–palladium mix, under catalogue numbers ZMUC KIN-1006 to KIN-1008. Fig. 1 The sampling localities of C. flosculosa sp. nov Yıldız et al. Helgol Mar Res (2016) 70:24 Page 3 of 13 Additional material from same date and locality as holo- in subdorsal and laterodorsal positions (Figs. 2a, 6a, 7a); type includes two specimens mounted in Fluoromount- sensory spots large, with a central pore, numerous short G and stored in the personal reference collection of the micropapillae, and a few considerably longer ones along first author, and three specimens, mounted for SEM, and the posterior margin. Cuticular hairs lightly scattered on stored in the personal reference collection of the second the dorsal and lateral sides (Fig. 6a); ventral side com- author. In addition, three specimens were collected on pletely devoid of hairs. Posterior segment margin ter- June 29, 2011 from intertidal sand at Kara Island (Fig. 1), minates into a well-defined pectinate fringe with short 36°59′08″N, 27°27′13″E by Nuran Özlem Yıldız, mounted fringe tips. for SEM, and stored in the personal reference collection Segment 2 consists of one tergal and one sternal plate. of the second author. Sternal plate partially differentiated into two plates by an epicuticular midsternal junction that, opposed to the Diagnosis midsternal junctions on the following segments, does not Segment 1 forming complete ring; segment 2 with one divide the ventral side into two articulating sternal plates tergal and one sternal plate, with complete tergosternal (Figs. 2b, 3b, d). Tergosternal lines well-developed. Long junctions, but only partially developed midsternal junc- tubes (23 µm from SEM) present in ventrolateral posi- tion; segments 3–11 with one tergal and two sternal tions (Figs. 2b, 5a). Sensory spots present in middorsal, plates. Middorsal spines present on segments 4–8; vent- laterodorsal (Figs. 2a, 6a, 7a) and ventromedial (Figs. 2b, rolateral tubes present on segments 2, lateroventral tubes 5a) positions; sensory spots more droplet-shaped on segment 5, lateroventral spines on segments 6–9, lat- than those on the preceding segment, and without the eral accessory tubes on segment 8, and midlateral tubes extended marginal hairs. Cuticular hairs lightly scattered on segment 10. Flosculum-shaped sensory spots present on the dorsal and lateral sides; ventral side with very few at posterior segment margins in midventral positions of hairs only, near the tergosternal junctions; ventromedial segments 3–8. and paraventral areas devoid of hairs but with longitu- dinal wrinkles in the cuticle. Posterior segment margin Etymology extend into midventral tip; pectinate fringe well-devel- The species is named flosculosa (L.), meaning “having oped, with conspicuously long and flexible fringe tips, or bearing little flowers”. The name was inspired by the