Cryptolaria prima Busk, 1857

Cantero, Álvaro Luis Peña, 2023, On some benthic hydroids from New Zealand deep waters, with the description of a new species, Zootaxa 5389 (2), pp. 241-252 : 250

Cryptolaria prima Busk, 1857

( Fig. 4e–h )

Cryptolaria prima Busk 1857: 173 , pl. XVI; Vervoort & Watson, 2003: 55–57 (synonymy).

Material examined. TRIP 5582/42, at least two colonies up to 180 mm high, with coppiniae ( NIWA 131516).

Description. Stems up to 180 mm high, completely polysiphonic. Stems giving rise to unbranched pinnae, up to 47 mm long, arranged in one plane in sub-opposite pairs. Pinnae with approximately constant diameter for most of their length, then tapering very gently distally, ending in a quite rounded tip. A few pinnae developing into branches or lower-order stems and giving rise in turn to pinnae.

Hydrothecae forming four longitudinal rows with an X arrangement. Hydrothecae not protruding far from peripheral tubes. Hydrotheca approximately cylindrical, distally bent outwards, adnate for about two-thirds of its adcauline wall. Free part of adcauline wall convex; adnate part straight or slightly convex. Abcauline wall roughly straight basally but concave distally. Aperture circular, directed upwards and outwards; rim even, often with renovations.

Nematothecae cylindrical, resting on a short pedicel; aperture circular.

Measurements (in µm). Hydrotheca: abcauline length 280–300, free adcauline length 140–170, adnate adcauline length 270–280, adcauline length 420–440, diameter at aperture 120–130, diameter at diaphragm 90. Nematotheca: height 80, diameter at aperture 25, maximum diameter 30, pedicel length 20.

Remarks. I refer this material to C. prima because of the presence of four longitudinal rows of hydrothecae with an X-arrangement, i.e. there are two alternating series on opposite sides of the pinnae. Present material also agrees with Busk’s species in the shape of the gonothecae, with the aperture laterally placed on a dome-shaped, hood-like structure, without the sharp projection typical of Cryptolaria pectinata ( Allman, 1888) .

Ecology and distribution. The material studied was collected at a depth of 175−206 m, off Snares Islands. Coppiniae present in March. The species is widely distributed in New Zealand waters ( Vervoort & Watson 2003).

Figures

FIGURE 4. (a–b) Clytia gigantea (Hincks, 1866): a, hydrotheca; b, cusps of hydrothecal aperture. (c–d) Sertularella valdiviae Stechow, 1923: c, part of stem showing hydrotheca and incipient branch; d, hydrotheca. (e–h) Cryptolaria prima Busk, 1857: e, part of stem showing hydrothecal arrangement; f–g, hydrothecae; h, nematotheca. Scale bar: 100 µm (b, h), 200 µm (a, c−g).