Hydroids of the BANZARE expeditions, 1929 – 1931: the family Haleciidae (Hydrozoa, Leptothecata) from the Australian Antarctic Territory
Author
Watson, Jeanette E.
text
Memoirs of Museum Victoria
2008
2008-12-31
65
165
178
http://dx.doi.org/10.24199/j.mmv.2008.65.9
journal article
7636
10.24199/j.mmv.2008.65.9
b20b7b3d-7fa7-4de7-87dd-9e00d48a6fa3
1447-2554
4630462
Halecium tubatum
sp. nov.
Figure 10A, B
Holotype
,
NMV
F147470,
Station
105, three microslides displaying several stems.
Paratypes
NMV
F147471,
Station
105, four microslides displaying colony.
NMV
F147472, one microslide displaying colony.
NMVF
147477,
Station
98, one microslide displaying colony.
NMV
F147480,
Station
90, one microslide displaying colony.
NMV
F147481,
Station 107
, one microslide displaying colony
.
Diagnosis.
Hydrorhiza reptant on hydroid host, stolons thin, tubular, rugose to smooth. Hydrocauli fragile, variable in length, to
4 mm
, unbranched; hydrocaulus above hydrorhiza weakly rugoseor with up to fourdeep annulations; hydrocaulus (pedicel) thereafter cylindrical, straight or weakly curved, walls smooth.
Pedicel bearing a single terminal hydrotheca; hydrotheca wide, bowl-shaped, walls flaring markedly from diaphragm to rim; rim circular, smooth, strongly outrolled, a row of desmocytes about halfway between diaphragm and rim. Afew secondary and succeeding hydrophores in linear row from diaphragm of hydrothecae; hydrophores widening to hydrotheca, a tumescence in perisarc above base.
Hydranths too few and too poorly preserved for description but possibly c. 20 tentacles.
Perisarc moderately thin throughout.
Gonotheca absent.
Measurements
(μm)
Remarks.
Although the sample is infertile, and most of the microslide preparations heavily stained green,
Halecium tubatum
can nevertheless be seen to differ widely from all other known species of
Halecium
.
It somewhat resembles
Halecium tenellum
Hincks, 1861
but that species is branched and the critical dimensions of the hydrotheca given by authors (
Ritchie 1907
, Cornelius 1995, Vervoort 1966,
Millard 1975
) are much smaller than those of
H. tubatum
.
Etymology.
The species is named for the trumpet-like hydrotheca