130 
Records of the Australian Museum (2009) Vol. 61 
0.02mm 
Figure 23. A-J, Hydroides spiratubus n.sp. (A) tube of paratype AM 
W202955. B-J, fromholotypeAMW21392: (B-G) bayonet-shaped 
special collar chaetae; (. H) thoracic uncini; (/) anterior abdominal 
uncini; (7) tip of posterior abdominal chaeta. 
(1923: 50, 1953: 641) from French Polynesia. Fauvel 
distinguished it from H. exaltatus (Marenzeller, 1884) on 
the basis that its modified coronal process is “a large hollow 
vesicle” which “takes the place of the great unpaired hook.” 
Fauvel (1923) adds that H. exaltatus var. vesiculosus “is a 
connecting link between H. exaltatus (Marenzeller) and 
H. albiceps (Ehrenberg).” However, Fauvel’s specimens 
from French Polynesia differ from both H. spiratubus and 
H. trivesiculosus in having a significantly higher numbers 
of coronal processes. According to Fauvel (1923: 49), they 
number about a dozen “Les dents du calice superieur, au 
nombre d’une douzaine, sont subegales recourbees en dehors 
et ter min ees croc emousse sans pointes laterales.” 
The third species that needs to be compared with is H. 
trivesiculosus Straughan, 1967. The corona of the former 
(Fig. 22B-E) consists of 9 processes (in both holotype 
and paratype). Its modified dorsal process is small, short, 
vesicular, and has a dorsolateral extension on each side as 
