86 
J.E. Watson 
Male and female gonothecae large, one to several borne 
near base of stem, inserted on a short indistinct pedicel beside 
apophysis; body narrowly conical, facing upwards, walls 
smooth to weakly undulated, distally truncate, closed by a 
sheet of tissue, immature female gonophore with many ova. 
Perisarc of stem and gonotheca moderately thick, thin on 
hydrothecal margin. Colonies colourless to white. 
Monotheca spinulosa, measurements, (p m) 
Hydrorhiza, width 
96-120 
Stem 
internode length 
228-320 
diameter at node 
30-50 
length of apophysis (adcauline wall) 
30-40 
Hydrocladium 
length of athecate internode 
32-56 
width at distal node (shoulder) 
40-60 
length of base of thecate internode 
(excluding spine) 
160-192 
length of subhydrothecal chamber 
199-200 
length of terminal spine 
18-64 
Hydrotheca 
length of abcauline wall (measured 
diagonally from base) 
156-200 
width of margin 
136-168 
Gonotheca 
length (excluding pedicel) 
1200-1560 
maximum width (at margin) 
640-740 
Nematotheca 
length of base 
22-32 
diameter of cup 
22-36 
Remarks. A microslide (NMV F59053) in the Bale collection 
of Museum Victoria labelled ‘ Plumularia spinulosa Bale 1882, 
Queenscliff’ was nominated as a probable syntype by Stranks 
(1993). As this is the only known specimen, by monotypy it is 
the holotype of the species. 
The position of the cauline nematotheca varies between 
colonies, typically being about halfway along the internode 
but sometimes only one-third the distance up from the 
proximal node. The position of the cauline apophysis is also 
somewhat variable, ranging from well below to close to the 
distal node. The axillar hydrostatic pore is very small and is 
only seen with careful searching. 
Stechow (1923) erected the var. obtusa for morphotypes 
with a blunt terminal hydrocladial spine and Ralph (1961b) 
erected the var. spinulosa for material from New Zealand with 
a long terminal spine. Later studies, including the present one, 
suggest the length of the spine is very variable. Watson (2005) 
suggested it may be a response to environmental conditions 
and evidence from this study supports this conclusion, 
specimens with the longest spines being from deeper, less 
turbulent habitat. 
M. spinulosa is a very small species with a preference for 
a substrate of flabellate red algae. 
Type locality. Queenscliff, Victoria, Australia. 
Known distribution. Temperate southern Australia to southeast 
Queensland, Lord Howe Island, New Zealand, Japan, South 
Africa, south Atlantic. Littoral to 100 m. 
Monotheca togata (Watson, 1973) 
Fig. 6 A-I 
Plumularia togata Watson, 1973: 191, figs 65-67.— Bouillon et 
al„ 2006: 371.- Stranks, 1993: 14. 
IMonotheca togata — Vervoort and Watson, 2003: 374, fig. 91A- 
E. 
Material examined. NMV F42060, holotype, microslide (malinol 
mounted), Pearson Island, South Australia, on red alga Metagoniolithon 
charoides, depth 33 m, coll: S. Shepherd 8 January 1969. Paratypes: 
microslides NMV F42061, F42062, F42063, F4G2064, F42065, 
F42066,F42105;SAMH40, Pearson Island onred algaMetagoniolithon 
charoides , coll: S. Shepherd, 8 January 1969. 
Description. Hydrorhiza a network of broad, flat stolonal tubes 
with internal flexion joints. Stems short, to 4 mm long, 
monosiphonic, with one to three short basal internodes, nodes 
transverse, succeeding internodes moderately long and slender, 
expanding distally to a broad shoulder at apophysis, a strong 
transverse septum above and below node at level of apophysis, 
distal node V-shaped, sometimes a weak transverse septum 
about halfway up internode near level of cauline nematotheca. 
Apophysis short, robust, just below distal cauline node, 
slightly frontal on stem, upwardly directed, abcauline wall a 
continuation of internode, adcauline wall set close to internode, 
distal end wide, thickened, node transverse, a weak oblique 
internal septum below node. 
Hydrocladia alternate, one on cauline internode, slightly 
forwardly directed, athecate internode very short, corrugated, 
a strong transverse internal septum, distal node transverse. 
Hydrothecate internode much longer than athecate internode, 
inserted into shoulder of athecate internode with a slender 
V-shaped joint; internode downwardly curved below 
hydrotheca. 
Hydrotheca cowl shaped (lateral view), scoop shaped 
(anterior view), with a distinctly peaked adcauline margin (i.e. 
opposite base of hydrotheca), prehydrothecal chamber short, 
inflated, upper (adcauline) wall strongly convex, sometimes a 
faint septum passing from internode into base, hydrothecal 
margin hemispherical to triangular (anterior view), in lateral 
view adcauline wall extending in a peak over margin; rim 
thickened and outrolled. 
Nematothecae bithalamic, moveable, all similar in shape 
but differing slightly in length of base, cup robust, wide and 
fairly shallow, adcaudally excavated almost to base; one 
cauline, about halfway along internode on same side as 
apophysis, one axillar beside apophysis, one median inferior 
on hump of prehydrothecal chamber, just reaching base of 
hydrotheca, twin laterals standing close together at either side 
of a low distal protuberance of internode, bases short, sides 
facing inwards to hydrothecal margin; in lateral view, 
nematothecae appear to be almost inside hydrothecal margin. 
Male gonotheca large, inserted on a short, straight pedicel 
