Styela

Styela sp. Material examined. St. B 2 -6, 1705m, many specimens. Remarks. Small, 3–6mm, flattened specimens which were probably attached by the wide area on the ventral side to a solid object are now in a too poor condition with the internal organs torn away. They appear to have one gonad on each side. Several features resemble S. coriacea (Alder et Hancock, 1848), however the recorded depth is too large for this species and due to the condition of the material the species cannot be identified.Published as part of Sanamyan, Karen & Sanamyan, Nadya, 2012, Deep-water Ascidiacea from the Sea of Japan, pp. 63-68 in Zootaxa 3245 on page 67, DOI: 10.5281/zenodo.28053

Pelonaia bursaria Redikorzev 1941

Pelonaia bursaria Redikorzev, 1941 (Figure 2) Pelonaia corrugata forma bursaria Redikorzev, 1941: 188. Pelonaia corrugata bursaria: Nishikawa, 1991: 129. Material examined. St. B 7-8, 532m, 1 specimen. Description. The single specimen is about 2.5 cm long and 1 cm diameter. The posterior end is rounded and an anterior extremity of the body has an abrupt narrowing where branchial and atrial orifices are set close together. The test is thin and firm. Hair-like processes with few attached sand grains are present only around the posterior end of the body and form a wide ring around it (Figure 2 A). Otherwise the test is smooth and not wrinkled (as in typical P. corrugata) and almost free from foreign matter with only occasional minute grains of sediment attached. Thick crowded circular muscles are present only on siphons while on the whole rest part of the body wall only occasional thin transverse muscle fibers can be detected after staining. In contrast the longitudinal muscles are well developed and continue to the end of the body, although muscle fibers are much thicker on its anterior half. About 18–20 branchial tentacles arise from the branchial velum. Prepharyngeal band runs close to the velum and draws a circular line with shallow dorsal V around large oval dorsal tubercle which has C-shaped opening. Dorsal lamina is a high plain-edged membrane. The branchial sac has one shallow but distinct fold on each side running on some distance from the dorsal lamina, otherwise its wall is quite smooth. Internal longitudinal vessels are very numerous and closely set, with no more than one stigmata between two adjacent vessels. The gut forms a deeply curved loop along postero-ventral end of the body, the secondary loop widely open and long rectum curves anteriorly at a right angle to the descending part of the loop. The stomach occupies about half of the length of the ascending limb of the gut loop, it has 22 prominent internal longitudinal folds and a small straight caecum on distal end. One gonad is on each side of the posterior half of the body wall. Long tubular ovary makes a widely open arc so that in most its way it runs more or less transversely in relation to the body axis. The ovary is surrounded by numerous crowded small oval testis follicles. The endocarps are rather large and present only on posterior half of the body: one endocarp is within the arc forming by each ovary, and several are on the body wall below (posterior) to gonads, including one endocarp in the gut loop. Remarks. The taxon was originally established by Redikorzev (1941) as a forma bursaria of Pelonaia corrugata Goodsir et Forbes, 1841 and then raised to a subspecies status by Nishikawa (1991). Original description is based on several specimens from the Sea of Okhotsk and Sea of Japan and no other specimens referable to this taxon were recorded until now. Redikorzev (1941) distinguished his 'forma' by several features which he thought are connected with the less elongated body in comparison with the typical P. corrugata, e.g. position of the gut loop and L-shaped instead of U-shaped gonads. However, as it become clear after examining of newly collected specimen, the differences appear to be more pronounced and Redikorzev's taxon probably deserves a rank of a separate species. The differences in the general shape of gonads in P. corrugata and P. bursaria are too prominent to be explained by different proportions of the body wall, and gonads differ not only in the shape but also in the form of male follicles, these are small, rounded or oval in P. bursaria and long sausage-shaped, mostly parallel to each other in P. corrugata. The stomach of P. bursaria is much shorter than in P. corrugata where it occupies almost entire ascending limb of the gut loop (see, for example Monniot, 2011, Fig. 6). Pelonaia corrugata has perfectly flat wall of the branchial sac, while P. bursaria has low but quite distinct branchial fold on each side. We reexamined several available small and large (2–8 cm) specimens of P. corrugata from the Sea of Japan and the mentioned features (flat branchial sac, very long stomach, the shape of gonads and endocarps) appear to be stable and not depending on the size of the specimens.Published as part of Sanamyan, Karen & Sanamyan, Nadya, 2012, Deep-water Ascidiacea from the Sea of Japan, pp. 63-68 in Zootaxa 3245 on pages 66-67, DOI: 10.5281/zenodo.28053

FIGURE 12. Distaplia alaidi. A in Shallow-water Ascidians from Matua Island (central Kuril Islands, NW Pacific)

FIGURE 12. Distaplia alaidi. A, preserved colonies; B, colony underwater; C and D, the same colony, enlarged to show details of cloacal opening and orientation of branchial siphons; E, zooids.Published as part of Sanamyan, Karen & Sanamyan, Nadya, 2017, Shallow-water Ascidians from Matua Island (central Kuril Islands, NW Pacific), pp. 301-321 in Zootaxa 4232 (3) on page 317, DOI: 10.11646/zootaxa.4232.3.1, http://zenodo.org/record/29368

Styela squamosa Herdman 1881

Styela squamosa Herdman, 1881 (Figure 3) Styela squamosa Herdman 1881, p 66. Sanamyan, Sanamyan, 2006: 321 (synonymy). Material examined. St. B 5 -11, 2651m, 6 specimens; St. B 5 -10, 2676m, 1 specimen; St. D 2 -8, 2653– 2683m, 1 specimen. Remarks. Oval, dark brown or almost black specimens are up to 2cm in greatest diameter. Thick short rhizoids are on the proximal end. The tunic is firm, warty, often covered by bryozoans and hydroids. External appearance and internal features correspond well to previous descriptions. Styela squamosa has wide range of distribution and is known from many deep-water localities in Pacific and around Antarctic. There are several records of this species from North Pacific, although the species has not been known from the Sea of Japan until the present record.Published as part of Sanamyan, Karen & Sanamyan, Nadya, 2012, Deep-water Ascidiacea from the Sea of Japan, pp. 63-68 in Zootaxa 3245 on page 67, DOI: 10.5281/zenodo.28053

Aplidium eborinum Sanamyan & Sanamyan, 2011, n. sp.

Aplidium eborinum n. sp. (Figures 4,5) Aplidium glabrum: Sanamyan, 1998: 119; 2000: 213 (part, specimens from Kamchatka); Sanamyan, Sanamyan, 2010: 242. Material examined. Kamchatka, Avacha Bay: Bezimanny Point, 6–8m, 7.08. 2004 (Holotype KBPIG 1442 / 1); Kekkurny Point, 19m, 26.07. 2006 (Paratype KBPIG 1443 /2, 2006-07- 26 -02); Piramidny Point, 18m, 14.02. 2007, several large colonies; Starichkov Island, 10–11m, 18.10. 2008, one colony (Paratype KBPIG 1444 / 3). Description. The colonies are thick encrusting masses with the surface raised into large domes or rounded stumpy lobes with large common cloacal apertures on the top. Sometimes the lobes are more separated and connected to each other only by thick anastomoses of the basal test (Figure 5 A). The largest collected colony is about 10 cm in extent and up to 5 cm thick. The colour is rather constant and varies in a limited degree from light yellowgrayish to white, sometimes with a light bluish opalescence on the underwater photographs. In preservative (formaline) all colonies are light grayish or brownish. The test is gelatinous and rather opaque, zooids are not visible well through it. The surface is always clear from foreign particles but sparse sand grains may present internally. Zooids are arranged along rather thick branching cloacal canals converging to sessile common cloacal apertures. In preservative the surface of the lobes is smooth, without depressions or ridges indicating systems. Zooids are rather short and in most preserved specimens strongly contracted, being no more than 7 mm long. They are almost parallel to each other and open at angle to the surface of the colony lobes. Branchial siphon has six lobes. Small atrial aperture has always simple and usually short atrial languet. Numerous closely set thin longitudinal muscles are on each side of the thorax. The branchial sac has 14 rows of stigmata. Cylindrical stomach has 13– 15 wide and usually very regular and prominent folds. Post pyloric part of the gut loop has usual duodenum, midintestine, posterior stomach and short wide rectal valves. Ovary consisting of one or two large ova is in the middle of postabdomen and testis follicles are confined to the posterior half or third of postabdomen. Up to six larvae incubated in the atrial cavity of some zooids in holotype. The trunk is 0.9mm long. There are three adhesive organs on long thin stalks and an arch of rather large and closely set epidermal vesicles arranged in a single row around each side of the anterior half of the larval trunk, but no median or lateral ampullae. Remarks. Colonies of this species from Avacha Bay were identified previously as A. glabrum (Verrill, 1971) described originally from Atlantic coast of North America. Indeed, they have similar zooids with almost the same number of rows of stigmata and stomach folds, although atrial languet in A. glabrum usually has additional lateral lobes completely absent in the specimens from Kamchatka. Colonies of A. glabrum are described as consisting of club-shaped flat-topped heads with abrupt sides which in larger colonies may have wide bases. We had a chance to examine colonies referable to A. glabrum from Norway, they consist of low flat-topped lobes with parallel vertical zooids open perpendicularly to the upper surface. These colonies correspond exactly to a schematic but quite precise figure provided by Millar (1966, Figure 14 a) and differ substantially from the colonies of the present species. It seems that A. glabrum is restricted to North Atlantic and European seas and probably not occurs in Pacific. Specimens from South Kurile Islands identified by Sanamyan (2000) as A. glabrum appear to be distinct from the present species, the structure of systems is not recognizable, the larva is very similar but smaller, and zooids have only 9 or rarely 10 rows of stigmata. However, the specimens from Kamchatka described in the same paper belong to A. eborinum n. sp., although Sanamyan (2000, Figure 2 D) misinterpreted the shape of systems in preserved colony and figured them as irregularly oval or circular.Published as part of Sanamyan, Karen & Sanamyan, Nadya, 2011, Shallow-water species of the genus Aplidium (Ascidiacea) from Kamchatka and Commander Islands, pp. 41-50 in Zootaxa 2922 on pages 46-47, DOI: 10.5281/zenodo.20800

Aplidium peruvianum Sanamyan & Schories 2004

Aplidium peruvianum Sanamyan & Schories, 2004 (Figure 5 E,F) Aplidium peruvianum Sanamyan, Schories, 2004: 193. Material examined: Chile, 4. region: Punta de Choros, Rhodymenia, 10m, two colonies; La gruta, 10m, one colony; Bajo tiburon, 17m, one colony; Las Tacas (Coquimbo), several colonies. Remarks. Originally described from the coasts of Peru the species is now recorded from Central Chile. It is characterized by hard massive colonies with distinctive circular, oval, or somewhat irregular systems of zooids separated by ridges of the test. The colonies and zooids resemble Atlantic species A. stellatum (Verrill, 1871), see Sanamyan & Schories (2004) and Sanamyan & Gleason (2009) for details.Published as part of Sanamyan, Karen, Schories, Dirk & Sanamyan, Nadya, 2010, New records of aplousobranch ascidians from Central Chile, pp. 58-68 in Zootaxa 2537 on page 61, DOI: 10.5281/zenodo.19666

Aplidium fuegiense Cunningham 1871

Aplidium fuegiense Cunningham, 1871 (Figures 5 C,D) Material examined: Chile, 10. region: Caleta Yerbas Buenas, 18m, one colony; 4. region: Punta de Choros, Bajo tiburon, 15m, one colony; La gruta, 30m, one colony. Remarks. Zooids of the present specimens agree with previous descriptions and colonies have small crowded oval bodies in the superficial layer of the tunic, a very characteristic feature allowing easy identification. In previous accounts, based on preserved material, the shape of colonies was described as extremely variable, and generally no obvious system of zooids could be recognized (Millar, 1960). Indeed, all examined preserved colonies are thick irregular masses without any recognizable systems. However, underwater photographs of the same specimens show that the shape of living colonies is rather characteristic: the surface is raised into several to numerous large conical lobes with a single cloacal siphon on the top of each lobe. Zooids open on the sides of these lobes and arranged along rather wide anastomosing cloacal canals converging to the top of the lobe (Figures 5 C,D). The material described by Van Name (1954) from Chile is certainly wrongly identified and consists of several species: reported number of stomach folds (12–24) is too high for A. fuegiense and range is too wide for one species.Published as part of Sanamyan, Karen, Schories, Dirk & Sanamyan, Nadya, 2010, New records of aplousobranch ascidians from Central Chile, pp. 58-68 in Zootaxa 2537 on pages 60-61, DOI: 10.5281/zenodo.19666

Aplidium falklandicum Millar 1960

Aplidium falklandicum Millar, 1960 (Figures 2 A, 5 A,B) Aplidium falklandicum Millar, 1960: 33; 1970: 100; Monniot & Monniot, 1983: 15 (synonymy). Material examined: Chile, 4. region: Punta de Choros, Rhodymenia, 10m, two colonies; La gruta, 25m, one colony. Remarks. Examined specimens have solid oval colonies with a rather small area of attachment. Zooids are in small circular or oval systems (Figure 5 A). The test is soft, gelatinous, transparent and colourless; the living specimens are whitish or colourless. Thread-like zooids are up to 10 mm long. Stomach wall has five longitudinal folds. According to Millar (1960) the number of rows of stigmata may vary from 12 to 23, a much wider range than occur in most Aplidium species. In the present specimens zooids have 12–14 rows of stigmata. Monniot & Monniot (1983) reported that the number of rows of stigmata is variable but rarely attain 16. Unusual white "thoracic triangles" described for this species by Millar (1960: 35) were not found in the present material. Other features of zooid agree well with the original description, and larva (Figure 2 A) is identical to those illustrated by Millar (1960).Published as part of Sanamyan, Karen, Schories, Dirk & Sanamyan, Nadya, 2010, New records of aplousobranch ascidians from Central Chile, pp. 58-68 in Zootaxa 2537 on pages 59-60, DOI: 10.5281/zenodo.19666

A new Culeolus species (Ascidiacea) from the NE Pacific, California

Sanamyan, Karen, Sanamyan, Nadya, Kuhnz, Linda (2018): A new Culeolus species (Ascidiacea) from the NE Pacific, California. Zootaxa 4420 (2): 270-278, DOI: https://doi.org/10.11646/zootaxa.4420.2.