Chone ungavana Chamberlin, 1920

Tovar-Hernández, María Ana, 2007, Revision of Chone Krøyer, 1856 (Polychaeta: Sabellidae) from North America and descriptions of four new species, Journal of Natural History 41 (9 - 12), pp. 511-566 : 561-563

Chone ungavana Chamberlin, 1920 incertae sedis

( Figure 18H–N )

Chone ungavana Chamberlin 1920, p 26 –27, Plate 4, Figures 1–4 .

Material examined

Type material. North West Territories [ CMN 1900-8369 (holotype) Hudson Strait, King George’s Sound, 62 ° N, 73 ° W, 64.3 m, coll. Low and Wakeham, Diana Expedition, September 1897] .

Additional material. Chone infundibuliformis KrØyer, 1856 [ ZMUC POL-1749 , lectotype; USNM-376, paralectotype; BMNH 82.5 .12.33, paralectotype] .

Description

Holotype dried out, complete but torn in thorax and abdomen. Branchial crown as long as half of the body length. Insertion of the branchial lobes exposed beyond collar, anterior peristomial ring lobe triangular, exposed beyond collar. Ventral margin of collar higher than dorsal. Dorsal margins forming two deep pockets. Radioles with broad flanges, radiolar tips short. Ventral shield of collar swollen. Thoracic uncini distributed as irregular double rows in tori, four rows of teeth above the main fang, hood present ( Figure 18I ). Bayonet chaetae ( Figure 18H ). Anterior abdominal uncini with four to five rows of teeth above the main fang, occupying half the length of main fang, main fang not extending beyond breast, breast rectangular ( Figure 18J, K ), posterior abdominal uncini similar to the anterior ones, but smaller ( Figure 18L, M ). Pygidium rounded ( Figure 18N ). Holotype female with oocytes in thorax.

Remarks

Holotype is dried out, no additional material is available, and there are no new records of this species since its description in 1920. From the holotype, only a few characters were recognized, two of them also being present in C. infundibuliformis . Chone ungavana and C. infundibuliformis have short radiolar tips, broad flanges and thoracic uncini distributed in two irregular rows in each torus. However, in C. ungavana the anterior peristomial ring lobe is exposed beyond the collar (not exposed in C. infundibuliformis ), and branchial lobes exposed beyond the collar (not exposed in C. infundibuliformis ). At this time it is not possible to recognize the validity of C. ungavana due to the dehydration of the only available material.

Figures

Figure 1. Chone albocincta. (A) Anterior end, dorsal view; (B) same, ventral view; (C) same, lateral view; (D) posterior end, latero-dorsal view; (E) anterior abdominal uncinus; (F) posterior abdominal uncinus; (G) radiolar tip; (H) thoracic uncinus; (I, J) paleate chaetae. [LACM-AHF 0455, paratype].

Figure 2. Chone aurantiaca. (A, D) Anterior end, dorsal view; (B, E) same, ventral view; (C) same, lateral view; (F) posterior abdomen; (G) thoracic segments; (H, J) radiolar tips; (I) dorsal pinnular appendages; (K) thoracic uncinus from chaetiger 5; (L–N) paleate chaetae; (O) elongate, hooded chaeta, median region; (P) anterior abdominal uncinus; (Q) posterior abdominal uncinus. (A–C, F, J, K, P, Q) [MCZ 1933, holotype]; (D, E, G–I, N, O) [USNM 43637]; (L, M) [FHL 1700].

Figure 3. Chone bimaculata. (A) Anterior end, dorsal view; (B) same, ventral view; (C) posterior end; (D, E) radiolar tips; (F, G) paleate chaetae; (H) bayonet chaeta; (I) thoracic, elongate, narrowly hooded chaeta; (J) thoracic uncinus; (K) anterior abdominal uncinus; (L) abdominal, elongate, narrowly hooded chaeta; (M–P) posterior abdominal uncini. (A–C, E–P) [USNM 36281, paratype]; (D) [RBCM 973-187-21].

Figure 4. Chone ecaudata (with methyl green staining). (A) Whole worm, ventro-lateral view; (B) anterior end, lateral view; (C) posterior thorax, lateral view showing oocytes; (D) anterior end, dorsal view; (E–G) same, ventral view. (A–C, F) [LACM-AHF 0183, paratype C. minuta]; (D, G) [USNM 17319, holotype C. ecaudata]; (E) [LACM-AHF 2472-53, 003213].

Figure 18. Jasmineira princei, Chone ungavana, and Euchone analis. (A) Anterior end, ventral view; (B) same, lateral view; (C) radiolar tip; (D) bayonet chaeta; (E) paleate chaeta; (F) thoracic uncinus; (G) abdominal uncinus; (H) bayonet chaeta; (I) thoracic uncinus; (J, K) anterior abdominal uncini; (L, M) posterior abdominal uncini; (N) posterior end; (O) vascular loops. (A–G) [BMNH 1921.5.1.4373, lectotype] Jasmineira princei; (H–N) [CMN 1900-8369, holotype] Chone ungavana; (O) [USNM 333] Euchone analis.