Jasmineira kikuchii, Nishi, Eijiroh, Tanaka, Katsuhiko, Tovar-Hernández, María Ana & Giangrande, Adriana, 2009

Nishi, Eijiroh, Tanaka, Katsuhiko, Tovar-Hernández, María Ana & Giangrande, Adriana, 2009, Dialychone, Jasmineira and Paradialychone (Annelida: Polychaeta: Sabellidae) from Japan and adjacent waters, including four new species descriptions, Zootaxa 2167, pp. 1-24 : 18-21

Jasmineira kikuchii new species

Figures 10–11

Material examined. Type material: HOLOTYPE — CBM –ZW 1015, Ariake Sound, St. AF7D, sandy mud, 17 m, N32.56959, E130.20054, dredge, 12 November, 2005, by K. Mori. PARATYPES — CBM-ZW 1016, Ariake Sound, St. AF7D, sandy mud, 17 m, N32.56959, E130.20054, dredge, 12 November, 2005, by K. Mori. CBM-ZW 1017, Ariake Sound, St. AF7D, sandy mud, 17 m, N32.56959, E130.20054, dredge, 12 November, 2005, by K. Mori. KMNH-IvR- 500.419, Ariake Sound, St. AF7D, sandy mud, 17 m, N32.56959, E130.20054, dredge, 12 November, 2005, by K. Mori. KMNH.Iv.R-500.420, Ariake Sound, St. AF7D, sandy mud, 17 m, N32.56959, E130.20054, dredge, 12 November, 2005, by K. Mori. OMNH-Iv5028, Ariake Sound, St. AF7D, sandy mud, 17 m, N32.56959, E130.20054, dredge, 12 November, 2005, by K. Mori. MNHN TYPE 1495 - Ariake Sound, St. AD20D, N32.31070, E130.14037, 20m, sandy bottom, 17 September, 2005, by dredge, by K. Mori. MNHN TYPE 1495 - Ariake Sound, St. AD20D, N32.31070, E130.14037, 20m, sandy bottom, 17 September, 2005, by dredge, by K. Mori. NHM-ANEA.2009.16, Ariake Sound, St. AG13D, N32.45080, E130.23005, 16m, 13 November, 2005, by dredge, by K. Mori. USNM 1123951, Ariake Sound, St. AG7D, N32.57023, E130.23052, 20m, sandy mud, 24 July, 2005, by dredge, by K. Mori. SAMA E 3726, Ariake Sound, St. AD20D, N32.31070, E130.14037, 20m, sandy bottom, 17 September, 2005, by dredge, by K. Mori. SMF 18134, St. AD20D, N32.31070, E130.14037, 20m, sandy bottom, 17 September, 2005, by dredge, by K. Mori. BPBM-R3393, St. AD20D, N32.31070, E130.14037, 20m, sandy bottom, 17 September, 2005, by dredge, by K. Mori. ZIHU-3806,St. AD20D, N32.31070, E130.14037, 20m, sandy bottom, 17 September, 2005, by dredge, by K. Mori. ZMB Vermes 11371, St. AD20D, N32.31070, E130.14037, 20m, sandy bottom, 17 September, 2005, by dredge, by K. Mori. MBM119723, St. AF8D, N32.56119, E130.20093, 27m, sandy mud, 12 November, 2005, by dredge, by K. Mori. MBM119724, St. AF8D, N32.56119, E130.20093, 27m, sandy mud, 12 November, 2005, by dredge, by K. Mori.

Description. Body cream colored, cylindrical. Body length 12 mm in holotype, 8.0–14.0 in paratypes, width 1.2 mm in holotype, 0.8–1.2 mm in paratypes. Tubes thin, membranous. Insertion of branchial lobes not exposed beyond collar. Branchial crown length 2.5 mm in holotype, 2.0–3.0 mm in paratypes. Radioles 10 pairs in holotype, 10–12 pairs in paratypes. Pinnules short, uniform length along radioles. Radiolar skeleton with two rows of cells. Radiolar tips 0.7–0.9 mm length ( Figure 11 D). Palmate membrane absent. Lateral flanges narrow. Dorsal lips triangular ( Figure 11 C). Ventral radiolar appendages 6 pairs in holotype, 4–6 in paratypes; longest similar to length of branchial crown ( Figure 11 C). Ventral lips rounded, light brown. Anterior peristomial ring lobe not exposed beyond collar, distally entire. Posterior peristomial ring collar cone-shaped, fused dorsally, with the epithelium from the anterior half semi-transparent, forming two well developed pockets; mid-dorsal collar margins forms narrow gap; lateral margins entire; ventral margin incised forming two well short ventral lappets ( Figures 10 A, 11A). Ventral margin slightly higher than dorsal ( Figure 10 B). A pair of white triangular glandular pads in both sides of bilobed margin of collar ( Figures 10 A, 11A). Ventral shield of collar extending to second thoracic segment, rectangular to trapezoidal shaped ( Figures 10 A, 11A). Ratio of posterior peristomial ring collar length versus chaetiger 2 length, in lateral view: 2.5:1. Narrow glandular girdle on chaetiger 2 ( Figure 11 A–B). Chaetiger 1: two groups of elongate, narrowly hooded chaetae. Chaetigers 2–8: notopodia – two irregular rows of elongate, narrowly hooded chaetae: one anterior row with bayonet chaetae; two posterior rows with paleate chaetae with very long tips ( Figures 10 D, 11G); neuropodia – one row acicular uncini with main fang surmounted by 3–4 rows of equal-size teeth, occupying proximal half of main fang ( Figures 10 E–F, 11H). Thoracic chaetigers uncini with long handles. Abdominal segments 28 in holotype, 25–34 in paratypes. Anterior segments with two rows of 6–7 elongate, narrowly hooded chaetae, chaetae from upper half as long as chaetae in lower row; 15–18 uncini per torus with the main fang surmounted by three rows of teeth, occupying half length of main fang ( Figure 10 G–H), older (dorsal most) uncini smaller than younger uncini (ventral-most), breast reduced to narrow swelling; handles long as thoracic uncini ( Figure 11 I). Posterior segments with one or two elongate, narrowly hooded chaetae, 50% longer than in anterior segments; 10 to 15 uncini per torus, similar to anterior abdomen and smaller ( Figure 10 I). Pygidium with triangular posterior margin with pygidial cirrus ( Figure 11 E).

Glandular pattern: After staining with methyl green, thorax stained only ventral and laterally. Anterior abdomen stained dorsally and ventrally, posterior abdomen not colored. Collar colored only in the basal half in lateral and ventral sides, dorsal parts not colored ( Figure 10 A–C). Anterior end of the ventral shield of collar not colored, posterior end dark.

Remarks: Jasmineira kikuchii is unique among the Jasmineira species in having (1) a pair of white triangular glandular pads in the ventral side of collar, as lung-shaped; (2) a long collar, cone-shaped with the epithelium from the anterior half semi-transparent; (3) a short pygidial cirrus; (4) a tiny glandular girdle on chaetiger 2.

On the pygidial cirrus, Jasmineira kikuchii is similar to J. analis Ehlers, 1908 , but the new species lacks lateral incisions of the collar (present in J. analis ) and has 10–12 pairs of radioles (3 pairs in J. analis ). On the ventral lobes of the collar, J. kikuchii , J. caducibranchiata Willey, 1905 , J. elegans Saint-Joseph, 1984 , J. filiformis Hartman, 1965 , J. pacifica Annenkova, 1937 and J. regularis Hartman, 1978 , have low and rounded mid-ventral collar lobes. Among them, J. filiformis and J. regularis have 4 and 5 pairs of radioles, respectively; J. kikuchii n. sp., have 10–12 pair of radioles; 8–12 pairs in J. elegans , 12 in J. caducibranchiata and 14–16 in J. pacifica . Additionally, the number of pairs of ventral radiolar appendages are also similar; 3 in J. caducibranchiata , 4–6 in J. elegans , 6–8 in J. pacifica , 4–6 in J. kikuchii n. sp., Jasmineira kikuchii n. sp., is distinguished from other species by the presence of mid-ventral white pads in collar.

TABLE I. Selected features of chonid sabellids from Japan.

Etymology: The specific epithet is given in honor of Dr. Taiji Kikuchi, a former director of the Amakusa Marine Biological Laboratory, Kyushu University, for his great contributions to marine biological research of the Ariake Sound and adjacent areas.

Figures

FIGURE 10. Jasmineira kikuchii sp. nov. A – C, ventral, lateral, and dorsal views, respectively, anterior end of methyl green stained holotype. D – I, SEM micrographs of chaetae and uncini. D, thoracic paleate chaetae from chaetiger 3. E – F, thoracicuncini from chaetigers 3 and 4. G – H, abdominal uncini from the anterior abdominal chaetigers. I, abdominal uncini from the posterior chaetiger. Scale: 1 mm in A – C.

FIGURE 11. Jasmineira kikuchii sp. nov. A – B, ventral (A) and dorsal (B) views of the holotype. C, inner view of crown of the holotype. D, radiolar tip of the holotype. E, posterior chaetigers and anal segment, showing anal cirri, holotype. F – I, chaetae and unicini from the paratype CBM-ZW 1016. F, thoracic narrowly hooded chaeta. G, paleate chaeta. H, thoracic uncinus. I, abdominal uncinus. Abbreviations: gg, glandular girdle; dl, dorsal lip; vl, ventral lip; vra, ventral radiolar appendage. Scale: 1 mm in A - E, 20 µm in F – I.