Halecium brevithecum Watson 2008

Halecium brevithecum Watson, 2008 (Fig. 4 A–C) Halecium brevithecum Watson, 2008: 168 –169, fig. 4 A–C. Material examined. Holotype, BANZARE Stn 41, 65° 48 'S 53 ° 16 'E (Enderby Land), 209 m, NMV F 147457, one microslide with a few stem fragments (longest c. 15 mm long). Diagnosis. Large,...

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Bibliographic Details
Main Author: Peña Cantero, Álvaro L.
Format: Other/Unknown Material
Language:unknown
Published: 2014
Subjects:
Online Access:https://zenodo.org/record/4630875
https://doi.org/10.5281/zenodo.4630875
Description
Summary:Halecium brevithecum Watson, 2008 (Fig. 4 A–C) Halecium brevithecum Watson, 2008: 168 –169, fig. 4 A–C. Material examined. Holotype, BANZARE Stn 41, 65° 48 'S 53 ° 16 'E (Enderby Land), 209 m, NMV F 147457, one microslide with a few stem fragments (longest c. 15 mm long). Diagnosis. Large, reddish, polysiphonic, irregularly branched stems. Branches originating either from abcauline side of hydrophore of primary hydrotheca or from inside hydrotheca. Usually, with ahydrothecate intermediate internode after apophysis. First hydrothecate branch internode distinctly longer. Hydrothecae alternately arranged in one plane. Hydrotheca at the end of short, adnate hydrophore. Hydrotheca very slightly widening distally; rim not everted. Adcauline hydrothecal wall adnate to internode. Hydrothecal aperture slightly directed downwards. No secondary hydrothecae present. Gonothecae unknown. Cnidome consisting at least of microbasic euryteles? Description. Thick, reddish stems. “Stem or branch fragments of a presumably larger colony. Stem (branch) fascicled, polysiphonic tubes varying from knotted to parallel. Branching irregular, ultimate branches monosiphonic” (Watson 2008: 169). Stem and branches divided into relatively short and thick internodes by alternately arranged, slightly oblique nodes (Fig. 4 B, C). Branches originating either just below hydrotheca on abcauline side (secondary branch more or less perpendicular to old one) or, more frequently, from inside hydrotheca. Usually, with ahydrothecate intermediate internode following apophysis (Fig. 4 A). First hydrothecate internode of branch distinctly longer (Fig. 4 A). Hydrothecae alternately arranged in approximately one plane. Hydrothecae low (Fig. 4 A–C), placed at end of adnate hydrophores; ratio between adcauline length of hydrophore and diameter at diaphragm 0.7 –1.0. Hydrotheca very slightly widening distally. Adcauline wall much higher than abcauline one, extending upwards on internode (Fig. 4 A–C). Adcauline hydrothecal wall adnate to internode. Hydrothecal ...