October, 1999 
SCAMIT Newsletter 
Vol. 18, No.6 
The discussion of Bight animals turned up a 
new Chone from Sta. 2330 off Ventura. It has 
a staining pattern similar to C. albocincta but 
no staining in the abdomen, and a relatively 
large dorsal separation of the collar. 
Ron introduced a Pherusa with ‘spindley 
spines’ and a Piromus from San Diego and 
Mission Bay. Leslie didn’t know the Pherusa 
and the Piromus she thought was probably P. 
capillata. 
Other specimens from Mission Bay included 
an acrocirrid, a large Cossura sp., a Neanthes 
(? acuminata) and a Hemipodus sp. General 
observation from Ron was that Mission Bay 
stations were extremely variable in their 
polychaete communities. Rick will put out a 
voucher sheet for the new Hemipodus. Ron 
also introduced a Eulalia sp (small with 
distinct ciliated bands starting on the 13th 
segment). 
Then someone brought out a cirratulid (they 
couldn’t be avoided any longer) and all 
semblance of order was shot. Chaetozone 
setosa specimens were agreed to represent a 
complex of species, but with the confusion in 
the literature (Blake’s name was used in vain) 
and absence of type specimens (again his name 
was used), they decided to leave all specimens 
fitting the general description as Chaetozone 
setosa. These are defined as all Chaetozone 
without a separation between cinctures in the 
posterior segments. 
Tony introduced some Chaetozone spinosal - 
characters included large extended head spines 
starting on setiger 35. There was some 
discussion that these specimens may be C. sp. 
L Other Chaetozone were C. sp. SD3 - (a 
harbor species with a defined staining pattern, 
dark setae, slight inflation at about setiger 20, 
long tapering prostomium and a dorsal ridge 
and small eyes, spines start at about setiger 40, 
the 3rd setiger separated from the 2nd at 1/2 
the length of the separation between the 1st and 
2nd) and C. senticosa (even staining pattern on 
the lateral sides of the peristomium and has 
few spines). 
The Aphelochaeta/Monticellina discussion 
uncovered controversy as to what is meant 
by“fimbriated” vs. “serrated” neurosetae. Both 
are visually similar at magnification 40X , but 
are the key characteristics for defining the 
genera. Distinction of the two genera on the 
basis of variable interpretation of these setal 
characters, often within the work of a single 
author, renders their use problematic. This is a 
central difficulty within this group, and 
SCAMIT needs to address it before any 
meaningful consensus on the definition of local 
cirratulid taxa can be obtained. This will come 
up with a vengeance during the B’98 QC 
sample exchange. Until it is resolved, the 
likelihood of having identical species in 
Aphelochaeta and Monticellina separated only 
by the interpretation of the marginal structure 
of the neurosetae is high. Such a separation/ 
duplication is unlikely to reflect reality. The 
presumption, in the case of such species pairs, 
is that definition of the setal character is 
suspect, and must be closely reconsidered. 
Rick suggested an easier character would be 
the relative length of the neurosetae to the 
notosetae (much shorter and sickle shaped in 
Monticellina , mostly). This, and other 
characters less problematic than the 
“fimbriated/serrated setae” need to be sought. 
The problems in cirratulids will not be 
resolvable until a character suite that can be 
more objectively used is developed. 
Some problems with the staining pattern of 
Aphelochaeta petersoni were discussed. Rick’s 
description and Blake’s MMS description do 
not match and both types are being observed in 
the samples. Consensus was that both types 
would be called A. petersoni. Aphelochaeta 
?multifilis ‘fimbriated’ neurosetae were 
observed under the compound scope. At 40x 
these setae resemble the serrated setae of a 
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