186 
Records of the Australian Museum (2009) Vol. 61 
Spirobranchus zelandicus n.sp. 
Fig. 62A-F 
Spirobranchus latiscapus .—Monro (1939: 152); non 
Marenzeller, 1885. 
Material examined. Holotype and paratype: 2 specimens, of which one 
is an adult (holotype) and the other, a juvenile found located on the latter 
(paratype), New Zealand, BMNH 1936.2.8.3047-3048, coll, from Discovery 
station 941, 40°51.4'S 174°48.2'E^1 0 55.8'S 174°46.7'E, dredge, 128-0 
m, 20 Aug 1932. Determined as Spirobranchus latiscapus (Marenzeller, 
1885): by Monro, Discovery Report, 1936: 192, and according to the label 
on the jar. Their registration numbers: holotype, NHM ANEA 2009.20, and 
paratype, NHM ANEA 2009.21. 
Description 
Measurements. (Holotype) tube 9.7 mm high at aperture, 
including MLR; latter alone 3.0 mm high; maximum width 
at its base, 5.7 mm; and 5.5 mm at its sides. Total length 
of worm 26.9 mm, its thoracic width 2.6 mm; length of 
operculum and peduncle 8.0 mm; operculum only, 1.6 mm, 
and its diameter 3.5 mm; length of abdomen 12.8 mm; 
number of abdominal segments 93. 
Tube. Tube surface of adult (holotype) and juvenile 
(paratype) covered over by a calcareous encrusting organism, 
with more or less transversely arranged apertures (Fig. 
62A). Upon removal of encrustation, tube colour beneath, 
white, with a faint caramel colour along MLR and fainter 
colour along transverse ridges and flanks. Height of tube, 
greater than its width; MLR high, continuous, sinuous, partly 
divided into triangular fin-shaped sections, some with nearly 
pointed tips, and projects anteriorly over tube aperture as 
a thick, prominent, forwardly directed process (Fig. 62A). 
Ventrolateral parts of tube chambered in places where not 
attached to the substratum. 
Worm. Operculum on left side; no rudimentary operculum on 
right. Opercular plate may either be tiered (4 plates) as in the 
holotype (Fig. 62B,C), or possess a single plate as in paratype 
(Fig. 62D,E). Viewed dorsally, opercular base and wings of 
juvenile broad and rounded laterally, and attached to the thorax 
by a comparatively narrow stalk (Fig. 62D,E). Peduncular 
wings unfringed (Fig. 62B,D). Radioles in holotype number 
37 on the left and 36 on the right; apparently in one and a 
half spirals in their contracted condition, but actually in a 
circle. Inter-radiolar membranes unfringed. Collar: broad 
(Fig. 62B,D). Thorax has 7 chaetigers; apron present (Fig. 
62B). Abdominal chaetae possess long shafts protruding from 
abdomen commencing about two segments from the anterior 
end; abdominal uncinal tori lateral (Fig. 62B). 
Chaetae. Special collar chaetae bayonet-shaped; a long part 
of shaft serrated distally; boss elongated, with curved outline; 
blade narrower than shaft, tapering, its serrations extending 
to its tip, its length shorter than combined length of serrated 
distal part of chaetal shaft and boss (Fig. 62F). Thoracic 
uncini bear 12 or 13 teeth, and anterior abdominal uncini 
9-11, in addition to the anterior serrated gouge. Anterior 
gouge characteristic: its sides pointed and directed outwards, 
while part in between is serrated (Fig. 621,J). Abdominal 
chaetae like flattened trumpets distally, with one side drawn 
out into tapering process (Fig. 62G,H). 
Remarks. Spirobranchus zelandicus n.sp., as shown in the 
present paper, is among a group of species belonging to the 
genus Spirobranchus that possess stacked opercula, although, 
according to several identifications in the literature, it was 
hitherto thought that there was only a single such species, 
namely, S. latiscapus (Marenzeller, 1885). 
Evidently, a number of species similar to S. latiscapus 
have been identified as such merely on the basis of their 
stacked opercular plates. Among them is S. zelandicus 
n.sp., from New Zealand. It is similar to S. zibrowii from 
the Kimberleys in possessing a many-tiered operculum (Fig. 
63E-J). However, the two species differ in the following 
respects. The tube of S. zibrowii is white to faintly bluish, and 
faint to darker-grey along the flanks. It has a high, thick, wavy 
MFR, which projects conspicuously beyond the aperture 
(Fig. 63A-D), and on either side of the MFR there is a very 
low, FFR. At the base of the MFR, as well as of each FFR, 
one either side of them, is a row small obliquely elongated 
foramina. On the other hand, the tube of S. zelandicus is 
white to faintly caramel coloured; and although it has a high, 
thick, MFR which projects conspicuously over the aperture 
as in S. zibrowii, it lacks FFRs and the rows of foramina 
characteristic of the latter (Fig, 62A). The operculum in 
S. zibrowii bears 2 to about 4 irregularly or incompletely 
formed and eccentrically laid plates, which may be on a short 
cylindrical column (Fig. 63E-J), and its opercular peduncle 
is fringed. On the other hand, the opercular plates in S. 
zelandicus are more regularly formed, and its peduncular 
wings are unfringed (Fig. 62B-E). The special collar chaetae 
of S. zibrowii are not bayonet-shaped, the distal part of the 
chaetal shaft is unserrated and a boss is absent (Fig. 63K), 
whereas, those of S. zelandicus are bayonet-shaped, possess 
a long serrated area, about as long as the blade itself, and 
prominent boss (Fig. 62F). Both S. zibrowii and S. zelandicus 
are different from Spirobranchus latiscapus (Marenzeller, 
1885) and other species described in this paper in several 
respects, including tube colour and form and chaetae. 
According to ten Hove (1994: 113), S. latiscapus has 
a wide Indo-West Pacific distribution, including New 
Zealand, and generally occurs below a depth of 50 m. Smith 
(unpublished thesis, 1985), deals with the S. latiscapus 
(Marenzeller, 1885) complex. The type locality of S. 
latiscapus is in Japan, near Eno-shima, Naze, Oshima 
(Marenzeller, 1885: 218-219). It was described under 
the genus Pomatostegus Schmarda, 1861. Benham (1916: 
158-159) transferred Pomatostegus latiscapus Marenzeller, 
1885 to the genus Spirobranchus mentioning among 
others, that its operculum “is calcareous instead of being 
of horny material.” Takahasi (1938: 215) also deals with 
it as Pomatostegus latiscapus, but earlier Benham (1916) 
showed it to be a Spirobranchus. 
Based on the original description of S. latiscapus by 
Marenzeller (1885: 218-219), its tube colour is pinkish- 
red; slightly triangular in cross-section, and has a median 
longitudinal ridge and one to several lateral longitudinal 
ridges bearing pointed processes or lamellae. Median 
longitudinal ridge is the most prominent. Sometimes only 
faint ridges present, or only a single lateral longitudinal 
ridge on each side, frequently only fine small spines or 
small pointed lamellae. Although Marenzeller had several 
specimens, the only complete had a total length of 27.5 mm 
(21.0 mm without its radioles), its operculum and peduncle 
6.5 mm. Operculum on left, the number of stacked opercular 
