Helgol Mar Res (2007) 61:167–182 DOI 10.1007/s10152-007-0064-9 ORIGINAL ARTICLE Loricifera from the deep sea at the Galápagos Spreading Center, with a description of Spinoloricus turbatio gen. et sp. nov. (Nanaloricidae) Iben Heiner · Birger Neuhaus Received: 1 August 2006 / Revised: 26 January 2007 / Accepted: 29 January 2007 / Published online: 10 March 2007 © Springer-Verlag and AWI 2007 Abstract Specimens of a new species of Loricifera, nov. are characterized by six rectangular plates in the Spinoloricus turbatio gen. et sp. nov., have been col- seventh row with two teeth, an indistinct honeycomb lected at the Galápagos Spreading Center (GSC) dur- sculpture and long toes with little mucrones. The SO ing the cruise SO 158, which is a part of the 158 cruise has yielded a minimum of ten new species of MEGAPRINT project. The new genus is positioned in Loricifera out of only 42 specimens. These new species the family Nanaloricidae together with the three belong to two diVerent orders, where one being new to already described genera Nanaloricus, Armorloricus science, and three diVerent families. This result indi- and Phoeniciloricus. The postlarvae and adults of Spi- cates a high diversity of loriciferans at the GSC. Nearly noloricus turbatio gen. et sp. nov. are characterized by all the collected loriciferans are in a moulting stage, a mouth cone with eight oral ridges and basally with a hence there is a new stage inside the present stage. This cuticular reinforcement named mouth cone pleat; prolongation of life stages and the occurrence of multi- eighth row with 30 whip-like spinoscalids and 30 “alter- ple life stages inside each other are typical of deep-sea nating” plates; thorax with eight single and seven dou- loriciferans. Here exempliWed by the two postlarvae ble trichoscalids, where the single trichoscalids are with adults inside, which is observed for the Wrst time twice the length of the double ones, and the secondary in Nanaloricidae. appendage on the double trichoscalid is smooth whereas the others are serrated; lorica with eight cutic- Keywords Loricifera · Nanaloricidae · Spinoloricus ular plates with additional spikes in the anterior cor- turbatio gen. et sp. nov. · Galápagos · SO 158 ners and intercalary plicae between the plates. Some of these genus-speciWc characters such as the mouth cone pleat, the “alternating” plates and the intercalary pli- Introduction cae have not been observed in Nanaloricidae before. The Higgins-larvae of Spinoloricus turbatio gen. et sp. The coastal interstitial fauna of the Galápagos Islands has been extensively studied by Prof. Peter Ax and a Communicated by H.-D. Franke. large team of co-workers and was published in about 40 articles mainly in the series Mikrofauna des Meer- I. Heiner (&) esbodens and the successor Microfauna Marina starting Zoological Museum, with the introductory article by Ax and Schmidt The Natural History Museum of Denmark, University of Copenhagen, (1973). Westheide (1991) summarized this mostly Ger- Universitetsparken 15, man information in an English review, which included 2100 Copenhagen, Denmark more than 390 species of the Galápagos meiofauna and e-mail: [email protected] several new records. Otherwise, the meiofauna of the W B. Neuhaus Central American East Paci c is poorly known. Mielke Museum für Naturkunde der Humboldt-Universität zu (1995) described six species of Copepoda from the Berlin, Invalidenstr. 43, 10115 Berlin, Germany coast of Costa Rica and provided evidence for the 123 168 Helgol Mar Res (2007) 61:167–182 repeated colonization of the Galápagos Islands and described from the Faroe Bank, North Atlantic possible speciation events in this taxon (Mielke 2003). (Heiner 2004). It was assumed for long that species of Guzmán et al. (1987) investigated coral reef meiofa- Nanaloricidae prefer shallow sandy waters (Gad 2004). una; Cruz and Vargas (1987) and Vargas (1988) However, this was recently disproved when a new reported meiofauna from mudXats at the Golf of genus and species, Phoeniciloricus simplidigitatus Gad, Nicoya in Costa Rica. All these studies mention meio- 2004 belonging to Nanaloricidae was described from fauna at group level. The kinorhynchs mentioned in the deep sea near the Kilinailau Trench close to Papua Cruz and Vargas (1987) and Vargas (1988) from the New Guinea (Gad 2004). Presently, only three other PaciWc coast of Costa Rica were assigned to Echino- Loricifera species are known from the deep sea; Plicil- deres and Kinorhynchus by the junior author (own oricus hadalis Kristensen and Shirayama, 1988 from unpublished results). Recently, a new genus of Kin- the Izu-Ogasawara Trench, Western PaciWc (Kristen- orhyncha, Fissuroderes has been collected and sen and Shirayama 1988), and Titaniloricus inexpecta- described from the continental shelf of Costa Rica and tovus Gad, 2005 as well as Pliciloricus pedicularis Gad, New Zealand (Neuhaus and Blasche 2006). 2005, both from the Angola Basin, Southeast Atlantic Concerning the deep-sea meiofauna in the Central (Gad 2005a, b). Very little is known about the life American East PaciWc area only one kinorhynch spe- cycles of deep-sea loriciferans, since most of the spe- cies has been identiWed to species level, Campyloderes cies are known from only a few specimens and com- cf. vanhoeVeni Zelinka, 1913 (Neuhaus 2004). The only plete series of instars are lacking. Hence, investigations other description of a deep-sea kinorhynch from the of these animals are highly desirable. American East PaciWc Deep Sea is Antygomonas oreas During the geological deep-sea expedition SO 158 Bauer-Nebelsick 1996 from a seamount at 500–700 m (MEGAPRINT = Multidisciplinary Examination of depth (Bauer-Nebelsick 1996). However, this record is Galápagos Plume Ridge Interaction), Dr Peter Götz from the northern, and not the central, part of the and the junior author had the opportunity to collect all American East PaciWc. Unpublished observations by biological material brought on board of R/V Sonne by the junior author based on material from the two Ger- petrological sampling and from Wve biological stations man deep-sea expeditions SO 144-3 and SO 158 with (Werner 2002). This paper is the third in a series about R/V Sonne in the Central American East PaciWc sug- the biological results of SO 144-3 and SO 158 to the gest a high diversity of Kinorhyncha and other meiofa- Galápagos area. una, such as Tardigrada and Gastrotricha in the deep sea, nearly all species being new to science. The phylum Loricifera consists of exclusively bilat- Materials and methods eral microscopic marine metazoans living either in the interstices of diVerent types of sand or in mud. The All specimens were collected with R/V Sonne during phylum including the type species Nanaloricus mysti- cruise SO 158 on and near the Galápagos Spreading cus Kristensen, 1983 was described in 1983 from shell Center (GSC) and in a transform fault zone in the Cen- gravel (Dentalium sand) oV the coast of RoscoV, tral American East PaciWc (Fig. 1; Werner 2002). Bio- France (Kristensen 1983). The type species belongs to logical material was obtained either by two sediment the family Nanaloricidae, which presently comprises traps (tube diameter 4 cm, tube length 21 cm) in a geo- three genera Nanaloricus, Phoeniciloricus and Armorl- logical chain sack dredge or by a meiofauna dredge. oricus (see Kristensen 1983; Gad 2004; Kristensen and Meiofauna was extracted by density gravity centrifuga- Gad 2004). In the genus Nanaloricus only two species tion with Levasil (Werner 2002). Sediment was imme- N. mysticus and Nanaloricus khaitatus Todaro and diately Wxed in 6–8% formaldehyde buVered with Kristensen, 1998 have been described (Kristensen buVer tablets for haematology at pH = 7.0 (Merck 1983; Todaro and Kristensen 1998), however, several 109468), carefully washed with plenty of tap water on a species are currently under description, e.g., a new spe- 40 m sieve about one day after Wxation, mixed with cies from Fort Pierce, USA (Kristensen et al. 2007) and Kaolin (Riedel de Haën 18616) centrifuged in a large- two new species from RoscoV, France (unpublished volume centrifuge Thermo Heraeus megafuge 3s with results by senior author). The genus Armorloricus, three times the amount of Levasil 200 A/40% (Bayer), including the two species Armorloricus elegans Kris- three times at 4,000 rpm, rinsed with tap water, stored tensen and Gad, 2004 and Armorloricus davidi Kris- in 75% ethanol, later transferred to an ethanol–glycer- tensen and Gad 2004 was described from RoscoV, ine mixture for 1–2 h, and the ethanol allowed to evap- France and shortly thereafter another species of this orate overnight. Individuals were placed in a tiny drop genus, Armorloricus kristenseni Heiner, 2004 was of pure glycerine on a cover slip, surrounded by paraYn, 123 Helgol Mar Res (2007) 61:167–182 169 Fig. 1 Map of study area of the deep-sea expedition SO 158. Land masses in dark grey, submarine ridges marked in light grey. Numbers next to black dots refer to sample sta- tions mentioned in the text. Map designed by courtesy of Reinhard Werner, IfM-GEO- MAR Kiel and carefully manipulated with a second coverslip after Table 1 Species list of the loriciferan fauna around Galápagos melting of the paraYne. Finally the coverslips were Spreading Center sealed with Glyceel prepared according to the recipe Nanaloricida by Bates (1997) and placed in a Cobb-aluminium slide Nanaloricidae for microscopic observation from both sides. For more Spinoloricus turbatio gen. et sp. nov. information concerning the density gravity centrifuga- Pliciloricidae Pliciloricus nov. sp. 1 tion method with Levasil (see Werner 2002; Neuhaus Pliciloricus nov. sp. 2 2004; Neuhaus and Blasche 2006). Pliciloricus nov. sp. 3 Rugiloricus nov. sp. 1 (cauliculus-type) Rugiloricus nov. sp. 2 (carolinensis-type) nov. gen. 1 et nov. sp. 1 Results nov. gen. 1 et nov. sp. 2 nov. gen.