Capitella jonesi ( Hartman, 1959 )

Magalhães, Wagner F. & Bailey-Brock, Julie H., 2012, Capitellidae Grube, 1862 (Annelida: Polychaeta) from the Hawaiian Islands with description of two new species, Zootaxa 3581, pp. 1-52 : 7-10

Capitella jonesi ( Hartman, 1959)

Figures 4 A–C, 5 A–F, 6 A

Capitellides jonesi Hartman, 1959: 156 –158, pl. 2, figs 1–3. Capitella jonesi - Warren 1976: 207. Blake 2009: 73–74. Capitella sp. III: Eckelbarger & Grassle 1987: 62 –76.

Material examined. Oahu Island: Maunalua Bay, Kawainui Beach Park near Niu Valley, 21°16ʹ43.3ʺ N, 157°44ʹ41.5ʺ W, Sept. 1992, coll. S.A. McCarthy and W.A. Estabrooks (reported in Dreyer et al. 2005), Sta. 1 post Hurricane Iniki (18, BPBM R3589); Sta. 4 post Hurricane Iniki (12, BPBM R3587); Sta. 7 post Hurricane Iniki (8); Sta. 10 post Hurricane Iniki (10, BPBM R3588).

Description. All specimens females; complete mature females 5.5–17 mm long, 0.1–0.15 mm wide for 59–85 chaetigers. Body elongate, slender, wider on mid-thoracic chaetigers, narrowing on abdomen; body rounded dorsally and with deep ventral groove beginning from chaetigers 6–7 and present throughout. Color in alcohol pale yellow.

Prostomium as long as peristomium, conical with rounded tip ( Figs 4 A, B, 5A, B); nuchal organs or eyes not observed. Peristomium distinct from prostomium, as long as prostomium and chaetiger 1, not forming complete ring ( Figs 4 A, B, 5A, B). Proboscis not observed.

Thorax with nine segments; females with chaetigers 1–3 with 4–5 unilimbate capillaries per fascicle ( Figs 4 A, B, 5A). Thoracic segments slightly enlarged after chaetiger 5, tapering after chaetiger 7 to beginning of abdomen ( Fig. 4 B). Thoracic chaetigers 4–9 with hooded hooks only; chaetigers 8–9 longer than anterior thoracic segments, biannulate ( Figs 4 A, B, 5A).

Abdominal segments not distinctly multiannulated anteriorly, at least twice as long as thoracic segments, with short hooded hooks throughout ( Fig. 5 A). Noto- and neuropodia with well separated glandular tori on posterior half of segment. Abdomen with 6–8 hooded hooks in anterior segments, reducing to 1–2 hooks posteriorly. Hooded hooks similar on thorax and abdomen—with moderate shaft, hoods not extending beyond main fang, with distinct node on shaft and, single row of teeth above main fang composed of enlarged middle tooth and two small lateral teeth ( Fig. 5 D–F).

Pygidium simple, anus terminal ( Figs 4 C, 5C).

Methyl green staining pattern. Thorax and abdomen staining with solid light green ( Fig. 6 A); chaetiger 6 staining slightly darker than rest of body ( Fig. 6 A); posterior end and pygidium not stained.

Distribution. Florida ( Hartman 1959); Massachusetts (Blake 2009) and newly recorded to Hawaii.

Remarks. Several preserved specimens had inflated thoracic segments and stretched abdominal segments without well-defined segmental grooves. These specimens also had an enlarged prostomium/peristomium and no distinct MGSP but were present at the same stations as the others and had the same chaetal arrangement.

The Hawaiian material was identified as Capitella jonesi by the unique chaetal arrangement of mature individuals. However, males and females of C. jonesi are known to possess genital hooks and only females without genital spines were encountered herein. Hartman (1959) described complete mature individuals with about 28 abdominal segments but the Hawaiian specimens had over 70 abdominal chaetigers. The arrangement of the teeth on the hook is identical to what is illustrated in Hartman (1959).

Biology. Mature females filled with eggs of 55–60 µm in diameter; see also Eckelbarger & Grassle (1987) and (Blake 2009).

Figures

FIGURE 4. Capitella jonesi: A, anterior end in lateral view; B, anterior end in dorsal view; C, posterior end with pygidium.

FIGURE 5. SEM of Capitella jonesi: A, anterior end in lateral view; B, anterior end in lateral view showing delimitations between prostomium, peristomium and chaetiger 1; C, posterior end with pygidium in ventro-lateral view; D – F, abdominal hooded hooks with a single row of 3 teeth above main fang.

FIGURE 6. Capitella jonesi: A, MGSP of anterior end in lateral view. Capitella minima: B, MGSP of anterior end in lateral view. Capitella sp.: C, MGSP of female individual; D, MGSP of male individual. Capitella teleta: E, MGSP of female individual; F, MGSP of male individual.