Clavadoce dorsolobata (Hartmann-Schröder, 1987) Hartmann-Schroder, 1987

Wilson, Robin S. & Greaves, Elizabeth, 2016, Clavadoce (Annelida: Phyllodocidae) from Australia, Zootaxa 4061 (1), pp. 61-67 : 62-65

Clavadoce dorsolobata (Hartmann-Schröder, 1987) comb. nov.

Figures 1 A–D, 2 A–D

Eumida (Sige) dorsolobata Hartmann-Schröder, 1987: 31 , figs 2–6.—1989: 15.—1990: 43.

Material examined. Type material: Australia: Victoria: Warrnambool, Breakwater Rock erosion terrace, at Aquarium, 22 Dec 1975, 38° 24.23´S 142° 28.53´E, 0–1m, G. Hartmann-Schröder, ZMH P18837, holotype.

Victoria: as for holotype, ZMH P18838, 1 paratype; Victoria: Point Lonsdale rock platform at lighthouse, 38° 17.48´S, 144° 36.92´E, 0–1 m, 24 Dec 1975, G. Hartmann-Schröder, ZMH P18839, 1 paratype.

Non-types: Australia: Victoria: Portland, Yellow Rock, Stn MRG 750, 38 º 23.33´S, 141º 35.1´E, 2 Feb 2012, 0–1 m, Marine Research Group of FNCV, MV F166892, 1; Portland Bay, Dutton Way, Stn MRG 755, 38 º 15´S, 141º 35´E, 2 Feb 2012, 0–1 m, Marine Research Group of FNCV, MV F166893, 1; Dutton Way, Portland north, Stn MRG 773, 38 º 19´S, 141º 35´E, Mar 2013, 0–1 m, MV F166895, 1; Port Campbell, west side of Harbour, Stn VNPMS 59, 38 º 37.5´S, 142º 59.5´E, 3 Mar 1996, 3.5 m, T.D. O'Hara, MV F90789 , 1; Cheviot Beach, Point Nepean, Stn WV 5, 38 º 18´S, 144º 40´E, 3 Mar 1998, 3.5– 5 m, T.D. O'Hara, MV F90787 , 2; Cheviot Beach, Point Nepean, Stn WV 5, 38 º 18´S, 144º 40´E, 3 Mar 1998, 3.5– 5 m, T.D. O'Hara, MV F166898, 2; Sorrento Back Beach, 38°20´S, 144° 45´E, 0–1 m, T. Costa, 2010, MV F109566, 1; Harmers Haven, south of Wonthaggi, 38º 39´S, 145º 35´E, 11 Mar 2015, 0–1 m, T.J. Hales, MV F166888, 1; Harmers Haven, south of Wonthaggi, 38º 39´S, 145º 35´E, 3 Jan 2012, 0–1 m, T.J. Hales, MV F166890, 1; Shack Bay, Cape Paterson, 38º 41´S, 145º 37´E, Apr 2012, 0–1 m, T.J. Hales, MV F183076, 1; Honeysuckle Point, Shoreham, Stn MRG 763, 38 º 26´S, 145º 4´E, 4 Apr 2012, 0–1 m, Marine Research Group of FNCV, MV F166891, 1; McHaffies Point, Phillip Island., Stn MRG 779, 38 º 28´S, 145º 14´E, 3 Apr 2013, 0–1 m, MV F166896, 1; Shoreham Beach, Stn MRG 783, 38 º 26´S, 145º 3´E, 24 Aug 2013, 0–1m, Falconer Audrey, MV F166897, 1; Shoreham Beach, Stn MRG 786, 38 º 26´S, 145º 3´E, 21 Sep 2013, 0–1 m, Falconer Audrey, MV F166894, 1; Gabo Island, Stn MRG 732, 37 º 30´S, 149º 50´E, 1 Jan 2011, 0–1 m, Marine Research Group of FNCVMV F166889, 1.

Other material, not examined. From Hartmann-Schröder (1989; 1990): New South Wales: Lake Macquarie, south headland at entrance, 33° 5.25´S, 151° 39.88´E, 0–1 m, ZMH, G. Hartmann-Schröder, 15 Jan 1976, 1; New South Wales: Maclean, Yamba, 29° 26´S, 153° 22´E, 0–1 m, G. Hartmann-Schröder, 18 Jan 1976, ZMH, 1 specimen.

Description. Holotype (ZMH P18837) 22 segments (complete but possibly regenerating posteriorly), 2.6 mm long. The new material reported here, all MV specimens, are larger, 27 chaetigers, 6.4 mm long, 0.7 mm maximum width to 50 chaetigers, 9.8 mm long, 0.45 mm maximum width. Two specimens (MV F109566, F166898) have pharynx fully everted: in both specimens basal two-thirds of pharynx is covered with evenly dispersed small rounded papillae, with about distal one-third of pharynx bare ( Figure 2 D). No terminal papillae visible. Prostomium ( Figure 2 B) 1.2 x wider than long, roughly rectangular but with rounded corners and narrowing slightly at posterior margin. One pair of oval red eyes, long axis oriented longitudinally, located slightly posterior to the middle of prostomium and are about half as long as prostomium. Frontal antennae and palps ( Figure 1 B) are located slightly back from the anterior margin of the prostomium, frontal and median antennae with distinctly narrowed tip section delineated by a constriction, bulbous with widest point at about first quarter of length, tapering basally and distally. Palps similar to frontal antennae but lack narrowed tip section. Median antennae ( Figure 1 B) similar in form and length to frontal antennae, inserted at midpoint of prostomium approximately level with anterior margin of eyes. Segment 1 reduced and not visible dorsally so that first pair of tentacular cirri appear to insert at posterior margin of prostomium, in total 4 pairs of tentacular cirri (1+2+1). Tentacular cirri (TC) similar in shape to antennae but slightly less bulbous at widest point and without sharply narrowed tip section ( Figure 2 B). Tentacular cirri of segment 1 and ventral TC on segment 2 twice as long as width of prostomium, dorsal TC of segments 2 and 3 longer, about 3 times width of prostomium. Dorsal cirri oval, symmetrical, about 1.6 x as long as maximum width. Neuropodium a simple symmetrical lobe, ventral cirri slightly asymmetrical, about as long as wide and with small but distinct point at distal end, long axis oriented obliquely dorsal relative to aciculum ( Figure 2 C). Body wall dorsally with distinct raised skin fold causing pair of raised areas dorsally near base of dorsal cirri, visible on most chaetigers on most specimens from about chaetiger 6–8 ( Figure 2 B, arrow). Anus a simple circle, oriented dorsally, with slightly raised and orange-pigmented margin. One pair of anal cirri, inserted ventral to anus, spherical in smallest specimens or oval in larger specimens, 1.6 x as long as maximum width ( Figure 2 C). Chaetae present from segment 2, compound and with shaft strongly serrated at articulation, blade short, evenly tapering and finely serrated at margin ( Figure 2 D).

Colour: Live specimens with one broad pale yellow dorsal band on each segment, prostomium and distal half of antennae, palps and tentacular cirri with brown pigmentation, dorsal cirri and anal cirri most strongly pigmented, varying from yellow to brown, ventral cirri similar but more pale ( Figure 2 A). Preserved specimens lose pigment but the same patterns are faintly visible, especially in dorsal and anal cirri.

Distribution and habitat. Southeastern Australia from western Victoria to northern New South Wales. Intertidal to 3.5 m, from algal turfs ( Figure 1 A).

Remarks. There is no doubt that this species belongs to Clavadoce as first recognised by Banse (1973): obliquely oriented ventral cirri, 3 fusiform antennae and uniramous parapodia are sufficient to confirm the generic placement. Clavadoce and Notophyllum are similar in having obliquely oriented ventral cirri, 3 fusiform antennae. Clavadoce is distinguished by having uniramous parapodia but the absence of a notopodial aciculum (and the presence of the structure in Notophyllum ) is difficult to observe, especially without damage to the specimens which have fragile parapodial appendages. Notophyllum , however, is also distinguished by the nuchal lobes, lateral rows of enlarged papillae on the pharynx and much larger dorsal cirri covering much of the dorsum (Kato and Pleijel 2002).

Our material agrees closely with the figures and description of Hartmann-Schröder (1987) and with the type material. The availability of colour photographs and two specimens with everted pharynx has allowed us to provide a more complete description of the species. The dorsal raised areas on dorsum near the base of the dorsal cirri were observed by Hartmann-Schröder (“… treten oberhalb der Parapodien längliche Lappen auf”) Hartmann-Schröder (1987, p.31) and is visible in most of our specimens ( Figure 2 B, arrows). This structure is easiest to see in photographs of living material where brown pigment helps to distinguish the raised patch.

The neurochaetae of our material ( Figure 2 D) are as figured by Hartmann-Schröder (1987, p.64, figure 6). However the neurochaetae are also similar to other described species of Clavadoce , for example Blake (1997, Figure 4.13C, C, splendida ; Figure 4.14C, C. nigrimaculata ). Chaetal morphology apparently does not provide characters for distinguishing species of Clavadoce .

We have not re-examined the specimens reported by Hartmann-Schröder (1989; 1990) from northern NSW, but it is not plausible that Hartmann-Schröder would have misidentified this distinctive species so we do not doubt this northern extent of the range. Clavadoce dorsolobata is now known to be widespread in shallow water algal turfs of southeastern Australia and is probably more common than the current limited records indicate. Even though Clavadoce dorsolobata is a small species and is easily overlooked, it is apparently absent from large MV collections of Phyllodocidae from southeastern Australia from shallow (5 m plus) and shelf depths, so it seems this species is confined to intertidal and shallow subtidal depths as indicated by the known specimens ( Figure 1 A).

Figures

FIGURE 1. Clavadoce dorsolobata (Hartmann-Schöder, 1987): A, locations where Clavadoce dorsolobata specimens are known; B, SEM anterior end, MV F 166895; C: SEM parapodia, chaetigers 26 – 28, MV F 166897; D, neurochaetae, chaetiger 17, MV F 166897.

FIGURE 2. Clavadoce dorsolobata (Hartmann-Schöder, 1987): A, dorsal view, live specimen, MV F 166896; B, dorsal view, anterior end, live specimen, MV F 166896; C, dorsal view, pygidium and anal cirri, live specimen, MV F 166894; D, lateral view, everted pharynx, fixed specimen, F 166898; A, B, C: photographs Leon Altoff; D: photograph David Paul.