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Taxon
Tasmanaria aegis Watson & Vervoort, 2001
Nomenclature
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Family: SertulariidaeGenus: Tasmanaria
SUMMARY
Hydrorhizae a thick plug of perisarc up to 25 mm wide or ramified, the stolons wound tightly around the host substrate.
Colonies heavily fascicled throughout; stems of large colony up to 8 mm thick at base, irregularly and arborescently branched more or less in one plane from just above base. Hydrocladia pinnate on branches, alternate, up to 50 mm in length, standing out stiffly at an angle of about 70° to branch from a short, tumid apophysis, a cauline hydrotheca on each side of hydrocladium and one opposite; hydrocladium athecate proximally, internodes few, but where present, nodes passing obliquely between pairs of hydrothecae.
Hydrothecae biseriate, immersed in internode, sub-alternate, laterally separate, tubular, narrowing almost imperceptibly from base to margin. Walls smooth, perisarc very thick, adcauline wall smoothly convex, almost entirely adnate. Some hydrothecae with a short free wall. Base of hydrotheca recurved into a terminal plug of perisarc, abcauline wall almost straight, sometimes a faint bulge opposite floor, usually a small internal peg of perisarc on abcauline wall opposite floor; an elliptical scar of varying size, infilled with thin perisarc, below some hydrothecae. Hydrothecal margin tilted upwards at an angle of 30°-40° to hydrocladial axis; margin circular, edentulate, with a thickened, slightly everted rim. Some hydrothecae with up to six close, submarginal replications; margin closed by a low operculum of one saucer-shaped valve, much torn and usually collapsed inward, a ring of minute internal opercular fragments usually adhering to the submarginal ring.
Hydranths with about 20 tentacles.
Gonothecae large, shield-shaped, perisarc very thick, borne without pedicel below a hydrotheca on distal half to third of hydrocladium, narrow at base, expanding distally, proximally lightly adpressed to hydrotheca then standing free, adcauline wall strongly convex, abcauline wall faintly convex to almost straight, produced into two large bluntly pointed spines, body of gonotheca narrowing between and above spines into a long tubular neck with broadly bilobate orifice, an embayment facing downwards to abcauline spines. No operculum visible. Gonophore spherical, occupying about half gonotheca, containing several large ova.
Colour: Honey brown.