Dear Paulo,
I just received a copy of this post from my advisor Dr. Lisa Levin. I am a
3rd year graduate student currently at the start of my field research about
the early life stages of market squid, *Doryteuthis *(formerly*
Loligo*)*opalescens
*, along the coast of San Diego, CA, USA. Specifically, I’m studying market
squid embryogenesis -happening at my sites as this is being written- and I
am investigating questions regarding critical spawning habitat. What I have
observed (based on 33 SCUBA dives) is that *Capitella sp.* infestations are
variable. When I do see them, they show up after a week or two following
the egg capsules being laid/attached to the benthos. At this time *Capitella
sp.* are very small (<1mm). Two to three weeks later towards the end of
squid embryogenesis the *Capitella sp.* are much bigger (>20 mm). Although
qualitative, it appears as though egg capsules with partially broken
membranes-exposing the gelatinous matrix-have a higher rate of infestation.
The way the membranes are broken appears variable and I have not been able
to determine if these breaks are initiated by *Capitella sp*. burrowing. I
have plans to make preliminary tests in the field and to determine if breaks
make the capsules more or less susceptible to a* Capitella sp.* association
and I am open to collaboration. Also, I am aware of an unpublished study by
Dr. Lou Zeidberg et al. that provides support that this is a commensal
relationship:
Zeidberg LD, Isaac G, Widmer CL, Neimeister H, Gilly WF (unpublished) *
Loligo* (recently renamed *Doryteuthis*) *opalescens* squid: egg capsule
hatch rate, hatch circadian rhythm, and symbiosis with the polychaete
*Capitella
ovincola. *25 pp.
_____________________________________________
Dear colleagues,
A friend of mine, Dr Erica Vidal, who is an specialist on cephalopod
cultivation, is interested in studying the infestation of *Loligo* egg
capsules by capitellids and nereidids. If you have the time and patience,
could you please have a look at the attached pictures? Do you know anything
about this kind of infestation? Could you provide any information about it?
Are you aware of any published (or unpublished) records on this subject?
Regards,
Paulo Lana
________________________________
Hi Paulo,
This will not be news to you, but for others Lynda Warren (1976) in her
Capitella review listed the putative Capitella taxa in squid eggs, which
included Hartman's Florida and California examples and Capitella
hermaphrodita of Boletzky & Dhole, 1967. Those author's title indicates
other polychaetes were noted but I haven't looked the paper up to see what
else they found.
Boletzky, S. v. ; Dohle, W. 1967: Observations sur un capitellidae
(Capitella hermaphrodita sp. n.) et d'autre polychetes habitant la ponte de
Loligo vulgaris. Vie et Milieu 18A: 79-98.
I wonder if the nereidid in the photo could be a member of the Neanthes
caudata species complex, which seem to love organic enriched places, and can
look rather like that?
*_______________________________________*
Dear Paulo,
When I was studying reproductive ecology of Capitella sp., I found that
capitella in Loligo egg capsules deposited in shallow water of inlet in
Vancouver Island of British Columbia (where I collected capitella from
intertidal and subtidal areas for regular experiments). I found that the
capitella living on capsules grew very fast, and become very large
individuals and produced many small eggs. I ended up running indoor
experiments by introducing juvenile capitella into egg capsules and found
some interesting results. The works were published in papers, which I do
not have reprints in hand any more. You may be able to find some
information from one or two of these publications.
Regards. Pei-Yuan
Qian PY. 1994. Effects of food quantity on growth and reproductive
characteristics of Capitella sp. (Annelida: Polychaeta). Invert. Reprod.
Devel., 26, 175-185.
Qian PY, Chia FS. 1992. Effects of diet type on the demographics of
Capitella sp. (Annelida: Polychaeta): lecithotrophic development versus
planktotrophic development. J. Exp. Mar. Biol. Ecol., 157, 159-179.
Qian PY, 1991. Impact of environmental factors on life history strategies
of the marine polychaete Capitella sp., Ph.D. Thesis, University of
Alberta, Edmonton, 271pp.
Qian PY, Chia FS. 1991. Fecundity and egg size of Capitella sp. were
mediated by diet. J. Exp. Mar. Biol. Ecol., 148, 11-25.
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