Naineris laevigata ( Grube, 1855 )

Zhadan, Anna, 2020, Review of Orbiniidae (Annelida, Sedentaria) from Australia, Zootaxa 4860 (4), pp. 451-502 : 480

Naineris laevigata ( Grube, 1855)

Figure 16

Aricia laevgata Grube, 1855: 112–113 , plate IV, fig. 6–8.

Naineris laevigata: Hartman, 1957: 297–298 , plate 35, figs. 1–8; Day 1967: 539–540, fig. 23.2 a–f; Day 1977: 237.

Material examined. Western Australia: Cottesloe Beach, 9.5 km west of Perth, 31°59’S, 115°45’E, 14.02.1970, depth 0.5 m, coll. H. Paxton, in calcaerous algae and Idanthyrsus (Sabellariidae) tubes, AM W.4365, 4 specimens.

Type locality. Mediterranean Sea.

Description. Body moderately long, cylindrical, thorax swollen in anterior part, slightly flattened in posterior; thoracic width 0.7–2.8 mm ( Fig. 16A, B ). Prostomium round or conical-round, flattened dorso-ventrally ( Fig. 16B, C ). Thoracic chaetigers numbering 11–18 ( Fig. 16B ). Branchiae from chaetiger 5–8, small triangular in thoracic chaetigers; in abdomen rapidly increasing in size, becoming long and wide, triangular with tapering tips, longer than notopodia ( Fig. 16C, E, F, H ). Thoracic notopodial postchaetal lobes developed from first chaetiger, wide foliaceous; in abdomen of same size and shape ( Fig. 16 B–F, H). Thoracic neuropodial postchaetal lobes triangular with wide bases and tips forming round papillae in upper part; in abdomen becoming smaller, triangular ( Fig. 16B , D–H). No subpodal, stomach or flange papillae, subpodal flange, interramal cirrus. Pygidium with papillate margin and four short cirri ( Fig. 16E ). Notopodial chaetae crenulate capillaries, in abdominal notopodia forked chaetae present ( Fig. 16F, H, I ). Thoracic neuropodia bearing three kinds of chaetae: crenulate capillaries, uncini, which can be thick smooth or thin curved and serrated, and thick curved subuluncini with long pointed tips ( Fig. 16F, G ). Abdominal neuropodia bearing thin capillaries and 3–4 projecting slightly curved aciculae ( Fig. 16H ).

Distribution. Tropical waters in Atlantic, Pacific and Indian oceans; Australia, Western Australia, New South Wales, Victoria, New Zealand.

Habitat. Intertidal, muddy sand, algae, sabellariid tubes.

Remarks. Naineris laevigata was described from the Mediterranean Sea. This species has a large morphological variability and wide distribution in tropical waters (Hartman 1957). Whether all populations belong to one species needs to be confirmed by thorough investigations of material from different localities. The specimens stud- ied here are in agreement with previous descriptions: Hartman (1957) based on material from Florida, Galapagos Islands, Hawaiian Islands and Peru; Day (1967) on material from South Africa.

Figures

FIGURE 16. Naineris laevigata, AM W.4365. A–E: stereomicroscope, methylene blue staining; F–I: compound microscope. A. General view; B. Anterior end, lateral view; C. Anterior end, dorsal view; D. Posterior thoracic chaetigers, lateral view; E. Pygidium, latero-posterior view; F. Parapodium of chaetiger 15; G. Neuropodium of chaetiger 15; H. Posterior abdominal parapodium; I. Abdominal notochaetae. a, acicula; br, branchia; cc, crenulated capillaries; fc, forked chaeta; ne, neuropodium; no, notopodium; su, subuluncini; u, uncini.