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Related to Peristomium: pygidium, Epitoky


n.1.Same as Peristome.
References in periodicals archive ?
the tentacular cirri longer; the peristomium as long as the following two segments .
Cerebral ocelli are defined here as being located in close association with the brain, within the peristomium or prostomium (excluding the radioles).
The peristomium consists of one or two achaetous rings (Blake, 1996; Glasby, 2000; SolisWeiss et al.
purpuratus immediately after they were stranded, and a week later they still scavenged desiccated remains of the sea urchins, usually by removing tissue through the peristomium (Ralston, pets.
Pigmentation: prostomium, caruncle, peristomium and chaetigers 1-3 with yellow-brown spots; in holotype last three chaetigers without pigmentation, preceding 17 chaetigers spotted with yellow-brown pigment, but decreasing in intensity anteriorly (Figs 5A, 5B).
number of anterior asetigerous segments, Laubier (1963) reported two for Cossura soyeri Laubier, 1963, naming the anterior one as the buccal segment or peristomium.
He described a pair of exocrine glands embedded in the subepithelial connective tissue of the ventro-lateral peristomium under the fold of the collar in Ficopomatus enigmaticus (Fauvel, 1923) (as Mercierella).
adventitium crawled anteriorly on the earthworm and "capped" the prey's prostomium, peristomium and anterior segments with its own head and anterior body.
Diagnosis: The caruncle is small and hidden by the overlying peristomium and 7 pairs of branchiae are present first occurring on the second setiger.
Biomineralization in the serpulids occurs at the first thoracic segment, where two tubular glands are located along lateral sides on the ventral shield of the peristomium (Fig.
The operculum (Figure 1a) is a thick muscular plate which forms the anterodorsal surface of the (fused) prostomium and peristomium.