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'Morphology.'Holotype: ZIHU 3926, intact specimen, fixed in 10% seawater formalin, preserved in 70% ethanol, among botryllid ascidian colonies, 42°16'N, 142°27'E, Higashi-shizunai, Hokkaido, Japan, 10 June 2010. Paratypes: ZIHU 3927, among botryllid ascidian colonies, 42°18'N, 140°59'E, Muroran, Hokkaido, Japan, 16 April 2010; ZIHU 3928, 3929, among laminarian holdfasts, 42°33'N, 141°55'E, Mukawa, Hokkaido, Japan, 9 June 2010; ZIHU 3930, 3931, among botryllid ascidian colonies, 43°01'N, 144°50'E, Akkeshi, Hokkaido, Japan, 23 June 2009; ZIHU 3932, 3933, same data as for holotype; ZIHU 3934–3937, among laminarian holdfasts, 42°33'N, 141°55'E, Mukawa, Hokkaido, Japan, 9 June 2010 [ZIHU 3927, 3933–3937, intact specimens, fixed in 10% seawater formalin, preserved in 70% ethanol; ZIHU 3928, dissected, with half of branchial crown removed; ZIHU 3929, 3930, whole mounts on slides; ZIHU 3931, serial sagittal sections on slide; ZIHU 3932, mounted on SEM stub].
One specimen, among algae, 42°18'N, 140°59'E, Muroran, Hokkaido, Japan, 19 April 2011.
ption. Body with eight thoracic and six abdominal chaetigers (Fig. 1A). Total length 2.8 mm, crown length 0.7 mm, maximum body width 0.3 mm. Three pairs of radioles, with lateral flanges; proximal 1/7 of radioles connected by palmate membrane; each radiole with six pairs of pinnules ending with terminal pinnule; all pinnules ending at same height as terminal pinnule (Fig. 1A). Each radiole with two longitudinal internal cellular supporting axes; each pinnule with one internal cellular supporting axis. One pair of ventral radiolar appendages present, with one internal cellular supporting axis, nearly 1/2 radiole length (Fig. 1A). One pair of elongate dorsal lips present, with neither pinnular nor radiolar appendages; one pair of triangular ventral lips present (Fig. 1B). Distal end of ventral lobe on anterior peristomial ring bifurcate (Fig. 2B). Posterior peristomial ring collar absent; border between anterior and posterior peristomial ring obscure (Figs 1B, 2A, 2B). Small ciliated patch on posterior peristomial ring (Figs 1B, 2A, 2B). One pair of red eyes present on peristomium (not visible in preserved specimens). Glandular ridge absent.
Superior thoracic notochaetae elongate, narrowly hooded, 3–5 per fascicle (Fig. 2C). Inferior thoracic notochaetae bayonet type, five per fascicle in first thoracic chaetiger; second to eighth thoracic chaetigers with 3–4 narrowly hooded and 5 bayonet-type inferior thoracic notochaetae (Fig. 2C). Thoracic acicular uncini 5–7 per torus; each uncinus with three rows of irregular-sized teeth above main fang (Figs 1C, 2D). Abdominal uncini quadrangular, with eight rows of teeth above large basal tooth (Figs 1D, 2E), 5–15 uncini per torus. Abdominal neurochaetae needle-like capillaries in form, three per fascicle (Fig. 2F).
Pygidium rounded, with one pair of red eyes; color of eyes faded in preserved specimens.
One pair of statocysts in first thoracic chaetiger evident in living state. Oocytes found in sixth to eighth thoracic chaetigers.
We obtained sequences for two of the three target gene fragments for this species (GenBank accession numbers AB646764, 18S, 1677 bp; AB646765, 28S-D1, 377 bp); we were unable to sequence 28S-D3–D7. Both strands were sequenced for 28S-D1; part of the 18S sequence is based on only one strand. Among species of Amphicorina, DNA sequence data were available only for Amphicorina mobilis (Rousset et al. 2004; Kupriyanova and Rouse 2008). In a 1687 bp alignment of 18S sequences, Amphicorina ascidicola differed in sequence from the Australian (GenBank accession number EF116206, Kupriyanova and Rouse 2008) and Japanese specimens (AB646764) of Amphicorina mobilis by 15 indels and 17 substitutions in each case. In a 321 bp alignment of the 28S-D1 region, Amphicorina ascidicola differed in sequence fromthe Australian (EF116217, Kupriyanova and Rouse 2008) and Japanese (AB646765) specimens of Amphicorina mobilis by five substitutions and one indel in each case.
The specific name, a noun, is a combination of ascidia (sea squirt) and -cola (dweller), referring to the fact that the species was frequently found among botryllid ascidian colonies.
Among the 38 congeners, the following eight species have been reported to exhibit a reduction in the collar [= absence of posterior peristomial ring collar] as in Amphicorina ascidicola: Amphicorina alata (Ehlers, 1897), Amphicorina brevicollaris (Rouse, 1990), Amphicorina gracilis (Hartman, 1969), Amphicorina grahamensis Giangrande, Montanaro & Castelli, 1999, Amphicorina minuta (Berkeley & Berkeley, 1932), Amphicorina neglecta (Banse, 1957), Amphicorina pectinata (Banse, 1957), and Amphicorina triangulata López & Tena, 1999. However, the present new species can be distinguished from those by the combination of characters and their states summarized in Table 2.
|Number of pairs of radioles||Number of pairs of ventral radiolar appendages||Ventral lobe on anterior peristomial ring||Number of abdominal chaetigers||Inferior tooth of abdominal uncini|
|Amphicorina alata (Ehlers, 1897)||4||1||absent||6||small||Ehlers (1897), Giangrande et al. (1999), López and Tena (1999)|
|Amphicorina brevicollaris (Rouse, 1990)||4||2||bifurcate||7||small||Rouse (1990), Giangrande et al. (1999), López and Tena (1999)|
|Amphicorina gracilis (Hartman, 1969)||3||0||absent||8||small||Hartman (1969), Giangrande et al. (1999), López and Tena (1999)|
|Amphicorina grahamensis Giangrande, Montanaro & Castelli, 1999||3||1||absent||5||large||Giangrande et al. (1999), López and Tena (1999)|
|Amphicorina minuta (Berkeley & Berkeley, 1932)||2||?||absent||5||large||Berkeley and Berkeley (1932), Giangrande et al. (1999), López and Tena (1999)|
|Amphicorina neglecta (Banse, 1957)||4||1||absent||6||large||Banse (1957), Giangrande et al. (1999), López and Tena (1999)|
|Amphicorina pectinata (Banse, 1957)||4||2||bifurcate||6||large||Banse (1957), Giangrande et al. (1999), López and Tena (1999)|
|Amphicorina triangulata López & Tena, 1999||4||1||bifurcate||6||large||López and Tena (1999)|
|Amphicorina ascidicola sp. n||3||1||bifurcate||6||large||Present study|
- Yoshihara, T; Hiruta, S; Katoh, T; Kajihara, H; 2012: Three species of Amphicorina (Annelida, Sabellida, Sabellidae) from Japan, with descriptions of two new species ZooKeys, 187: 45-62. doi
- Rousset V, Rouse G, Siddall M, Tillier A, Pleijel F (2004) The phylogenetic position of Siboglinidae (Annelida) inferred from 18S rRNA, 28S rRNA and morphological data. Cladistics 20: 518-533. doi: 10.1111/j.1096-0031.2004.00039.x
- Kupriyanova E, Rouse G (2008) Yet another example of paraphyly in Annelida: molecular evidence that Sabellidae contains Serpulidae. Molecular Phylogenetics and Evolution 46: 1174-1181. doi: 10.1016/j.ympev.2007.10.025
- ICZN (1999) International Code of Zoological Nomenclature. International Trust for Zoological Nomenclature, London, 306 pp.
- Ehlers E (1897) Polychaeten der Hamburger magalhaenischen Sammelreise. Ergebnisse der Hamburger magalhaensischen Sammelreise Liefersung 2: 1-147.
- Giangrande A, Montanaro P, Castelli A (1999) On some Amphicorina (Polychaeta, Sabellidae) species from the Mediterranean coast, with the description of A. grahamensis. Italian Journal of Zoology 66: 195-203. doi: 10.1080/11250009909356255
- López E, Tena J (1999) A new species of Amphicorina (Polychaeta: Sabellidae: Sabellinae) from the Chafarinas Islands (Western Mediterranean). Cahiers de Biologie Marine 40: 329-335.
- Rouse G (1990) New species of Oriopsis and a new record for Augeneriella cf. dubia Hartmann-Schröder, 1965 from eastern Australia (Polychaeta: Sabellidae). Records of the Australian Museum 42: 221-235. doi: 10.3853/j.0067-1975.42.1990.116
- Hartman O (1969) Atlas of the Errantiate and Sedentariate Polychaetous Annelids from California. Allan Hancock Foundation, Los Angeles, 812 pp.
- Berkeley E, Berkeley C (1932) On a collection of littoral Polychaeta from the West Coast of Vancouver Island. Contributions to Canadian Biology and Fisheries 7: 311-318. doi: 10.1139/f32-024
- Banse K (1957) Die Gattungen Oriopsis, Desdemona und Augeneriella (Sabellidae, Polychaeta). Videnskabelige Meddelelser fra Dansk Naturhistorisk Förening i Kjöbenhavn 119: 67-105.