FIGURE 5. Spionid adult morphology. A in Spionidae (Annelida) from shallow waters around the British Islands: an identification guide for the NMBAQC Scheme with an overview of spionid morphology and biology

FIGURE 5. Spionid adult morphology. A, Prionospio sp., anterior end, left lateral view, long pinnate branchiae on segments 2 and 5, smooth robust branchiae on segments 3 and 4, and dorsal crests on postbranchiate segments, palps missing. B, Laonice cirrata, anterior end, left lateral view, left palp missing, deep longitudinal frontal groove on right palp sided by undulating edges and lined with short cilia. C, Microspio sp., anterior end, ventral view, bifurcated prostomium, dorsal and dorso-lateral ciliated folds of foregut, and large ventral lip of peristomium fused to the first segment. D, Spiophanes sp., middle segments, dorsal view, metameric nuchal organs, dorsal ridges bearing long and dense nototroch cilia on top, and subulate notopodial postchaetal lamellae. E, Scolelepis sp., basal parts of palps, basal sheath with papillae on edge. F, Scolelepis sp., fragment of head and palp bases, frontal view, indistinct sheaths tightly fused to basal parts of palps. bs—basal sheath on palp; dc—dorsal crest; dl—dorso-lateral ciliated fold of foregut; do—dorsal ciliated fold of foregut; gr—longitudinal frontal groove on palp; lc—intersegmental lateral longitudinal ciliation; lo—lateral ciliated organ; no—notopodial postchaetal lamella; nt—nototroch; nu—nuchal organ; pa—palp; pb—proboscis; pr—prostomium; ps—papilla on basal sheath on palp; s1—segment 1; vp— ventral lip of peristomium. Scales: A, C–E—100 µm. B—200 µm. F—50 µm.