Chone kroyerii Sars 1862
Creators: name: Tovar-Hernández, María Ana
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Sabellida
Sabellidae
Chone
Chone kroyerii

description: Chone kroyerii Sars, 1862
Figure 8
Chone kr ø yerii Sars, 1862: 35 –37.— Cochrane, 2000: 144 –145.
Material examined. Non-type material. Bogestr Ø mmen [ZMO] (1).
Additional material. Chone duneri Malmgren, 1867 [ZMUC POL –1755, Norway]. Chone infundibuliformis Kr ø yer, 1856 [ZMUC POL –1749, paralectotype].
Description. Colour, body shape, and size. Body cream-coloured, no branchial crown. Trunk cylindrical. Body length 24 mm, width 0.4 mm. Tube unknown.
Branchial lobes and branchial crown. Insertion of the branchial crown not exposed beyond collar (Fig. 8 B).
Peristomium. Anterior peristomial ring lobe (aprl) not exposed beyond collar, distally entire, triangular (Fig. 8 B). Posterior peristomial ring collar: antero-dorsal, ventral and lateral margins entire, ventral margin higher than dorsal (Fig. 8 D); longitudinal grooves on dorsal side of collar; entire length of mid-dorsal collar margins forms a broad gap (Fig. 8 B). Dorsal pockets well developed. Ventral shield of collar rectangular (not easily discernible). Ratio of posterior peristomial ring collar length versus chaetiger 2 length, in lateral view: 2:1.
Thorax. Chaetigers 2 to 8: notopodia– two irregular rows of elongate, narrowly hooded chaetae; one anterior row with narrow bayonet chaetae (Fig. 8 H); two posterior rows with symmetrical; paleate chaetae with a medium-sized mucro (Figs 8 E–G); neuropodia– two irregular rows of acicular uncini per torus, main fang surmounted by three rows of teeth (Fig. 8 J), second tooth enlarged, located in the midline, dentition covering one quarter of the main fang length. Glandular ridge on chaetiger 2: narrow.
Abdomen. Abdominal segments: 51. Anterior abdominal uncini with the main fang surmounted by five rows of teeth equal in size (Fig. 8 K), occupying less than half the length of main fang, main fang not extending beyond breast, breast rectangular. Posterior abdominal uncini with four rows of teeth equal in size (Fig. 8 L). Very long, narrowly hooded chaetae (Fig. 8 I). Pygidium with triangular posterior margin (Fig. 8 D).
Gametes. Male with spermatozoa in thorax and abdomen: acrosome elongate, triangular, nucleus barrelshaped, two rounded mitochondria (Fig. 8 C).
Methyl green staining. Collar dorsal and lateral surfaces completely stained (Figs 8 B, D), collar ventral surface coloured only the base of the ventral collar shield (Fig. 8 A), other areas with small dark points. Thorax dorsally less stained than ventrally (Fig. 8 B).
Remarks. Sars (1862) stated that the specimens resembled Chone paucibranchiata (Kr ø yer, 1856) to such an extent that he was long predisposed to assume that taxon; however, the number of radioles is not a character to differentiate species and the biannulate condition in thoracic segments is a common pattern in Chone. Chone kroyerii was referred to C. infundibuliformis by Malmgren (1866) and Fauvel (1927), but Cochrane (2000) recognized this taxon as valid. Chone kroyerii, C. duneri and C. infundibuliformis have anterior and posterior abdominal uncini with similar shape (not modified); C. kroyerii and C. infundibuliformis have the branchial lobes not exposed beyond collar (exposed in C. duneri); C. kroyerii has a broad collar gap (narrow in C. infundibuliformis), and the ventral margin of collar higher than C. infundibuliformis. Among species of Chone included in this revision, C. kroyerii is unique by having a rectangular ventral shield of collar (Table 2).
description: Published as part of Tovar-Hernández, María Ana, 2007, On some species of Chone Krøyer, 1856 (Polychaeta: Sabellidae) from world-wide localities, pp. 31-68 in Zootaxa 1518 on pages 45-46, DOI: 10.5281/zenodo.177378