Chone costulata ( Grube, 1877 ), Grube, 1877

Tovar-Hernández, María Ana, 2007, On some species of Chone Krøyer, 1856 (Polychaeta: Sabellidae) from world-wide localities, Zootaxa 1518, pp. 31-68: 39-42

publication ID

http://doi.org/ 10.5281/zenodo.177378

publication LSID

lsid:zoobank.org:pub:B0C3B3D8-4806-4C6D-A6B9-4670C919EDDB

DOI

http://doi.org/10.5281/zenodo.5697310

persistent identifier

http://treatment.plazi.org/id/03CE472C-FFBC-FF9A-FF7A-F8DAFDE098A0

treatment provided by

Plazi

scientific name

Chone costulata ( Grube, 1877 )
status

new combination

Chone costulata ( Grube, 1877)   new combination

Figure 5 View FIGURE 5

Sabella costulata Grube, 1877: 548   –549.

Material examined. Type material. K ē rgu ē len [ ZMB 894, holotype], Great Whale Bay, 24.1 m, Expedition Gazelle.

Additional material. Chone gracilis Moore, 1906   [ USNM 5513, holotype], [ ANSP 1–24, paratype]. Description. Colour, body shape, and size. Body cream coloured. Holotype incomplete (no posterior abdomen). Body length 25 mm, width 6 mm. Tube unknown.

Branchial lobes and branchial crown. Insertion of the branchial crown not exposed beyond collar ( Fig. 5 View FIGURE 5 A). Branchial crown length 24 mm. Radioles: 19 pairs. Radioles with median pinnules three times longer than more proximal pinnules. Radiolar tips medium-sized ( Fig. 5 View FIGURE 5 D). The palmate membrane extends about three quarters the length of the branchial crown. Lateral flanges narrow ( Fig. 5 View FIGURE 5 D). Dorsal lips broadly rounded, as long as wide, without mid-rib. Dorsal pinnular appendages: one short pair. Ventral lips rounded, as long as wide, about one quarter the length of the dorsal lips. Ventral radiolar appendages: 8 short pairs (less than one quarter the length of the branchial crown length).

Peristomium   . Anterior peristomial ring lobe not exposed beyond collar, distally entire, triangular. Posterior peristomial ring collar: antero-dorsal ( Fig. 5 View FIGURE 5 A) and lateral margins entire ( Fig. 5 View FIGURE 5 C), ventral margin higher than dorsal, incised ( Fig. 5 View FIGURE 5 B); longitudinal grooves on ventral side of collar; entire length of mid-dorsal collar margin forms a broad gap ( Fig. 5 View FIGURE 5 A). Dorsal pockets well developed ( Fig. 5 View FIGURE 5 A). Ventral shield of collar swollen, horseshoe-shaped, three times wider than long ( Fig. 5 View FIGURE 5 B). Ratio of posterior peristomial ring collar length versus chaetiger 2 length, in lateral view: 1.5: 1.

Thorax. Chaetigers 2 to 8: notopodia– two irregular rows of elongate, narrowly hooded chaetae; one anterior row with bayonet chaetae; two posterior rows with symmetrical; paleate chaetae with a medium-sized mucro; neuropodia– two irregular rows of acicular uncini per torus, main fang surmounted by three rows of teeth ( Fig. 5 View FIGURE 5 F), second tooth enlarged, located in the midline, dentition covering one quarter of the main fang length (not illustrated). Glandular ridge on chaetiger 2: narrow.

Abdomen. Abdominal segments: 7. Anterior uncini with the main fang surmounted by four rows of teeth equal in size, occupying less than half the length of main fang, main fang not extending beyond breast, breast rectangular ( Fig. 5 View FIGURE 5 G). Posterior uncini similar but with three rows of teeth ( Figs 5 View FIGURE 5 H). Pygidium unknown.

Gametes. Holotype mature male, spermatozoa with barrel-shaped nucleus, triangular, elongate acrosome and two rounded mitochondria ( Fig. 5 View FIGURE 5 E).

Methyl green staining. Ventral shield of collar stains uniformly, except for a transversal, M-shaped median line ( Fig. 5 View FIGURE 5 B); lateral and dorsal sides of collar darker than following segments ( Fig. 5 View FIGURE 5 C). Thorax and anterior abdomen with epidermis completely glandular, stains uniformly, dorsal and ventrally ( Figs 5 View FIGURE 5 A–C), except for the faecal groove ( Fig. 5 View FIGURE 5 A).

Remarks. Sabella costulata   is transferred to Chone   because it has branchial lobes fused dorsally; palmate membrane and radiolar flanges present; dorsal lips broadly rounded, as long as wide, without mid-rib; ventral lips present, broadly rounded; dorsal pinnular appendages present; ventral radiolar appendages present; glandular ridge on chaetiger 2; elongate, narrowly hooded chaetae, bayonet and paleate chaetae, acicular uncini with second tooth enlarged, located in the midline; anterior and posterior abdominal uncini with well developed rectangular breast, handles absent, main fang well developed, few rows of small teeth covering one half (or less) of the main fang length.

The unique distinctive features of C. costulata   are: anterior margin of collar incised ventrally; entire length of mid-dorsal collar margin forms a broad gap; dorsal pockets well developed; and ventral collar shield is horseshoe-shaped with a median, transversal M-shaped line. Other species with the ventral margin of collar incised is C. gracilis   , however, the holotype of this species has the incision probably due to a regeneration process; in the paratype it is entire.

ZMB

Museum für Naturkunde Berlin (Zoological Collections)

USNM

Smithsonian Institution, National Museum of Natural History

ANSP

Academy of Natural Sciences of Philadelphia

Kingdom

Animalia

Phylum

Annelida

Class

Polychaeta

Order

Sabellida

Family

Sabellidae

Genus

Chone

Loc

Chone costulata ( Grube, 1877 )

Tovar-Hernández, María Ana 2007
2007
Loc

Sabella costulata

Grube 1877: 548
1877