Groups of ctenidia
cover the internal surface of the sheaths throughout its length (Figs.
This point of tissue fusion is joined to the posterior tips of ctenidia
as in D.
Tip of male fixed cheliceral finger rounded, tapering anteriorally, palpal tarsus dark for at least the distal half, metatarsus dark 80% apically, dusky creamy orange chelicera, dark to dusky light orange propeltidium; ctenidia
short (about half the succeeding segment), pointed.
Furthermore, feeding studies with the blue mussel (Mytilus edulis Linnaeus, 1758) indicate that high algal concentrations can severely overload the ctenidia
and reduce filtration rates (Riisgard et al.
The posterior tail region includes the single fused gonopericardial duct, the intestine, and the most posteriorly situated knob with the hemocoel, gametoduct, rectum, and a pair of bipectinate ctenidia
in the bell-like mantle cavity.
Posterior border of second post-spiracular sternite with a row of about 50 ctenidia
Abdomen with lateral ctenidia
in segments V-VIII, transverse comb complete on segment VIII, teeth separated.
Endosymbionts observed on histological examination included Rickettsia-like organisms (RLOs) in the ctenidia
(n = 246); an unidentified metazoan parasite in the siphon epithelium (n = 220); and microsporidia-like species in the intestine (n = 103), siphon muscle (n = 28), and ova (a Steinhausia-Wke parasite; n = 99).
Endoscopic visualization of the functional morphology of the ctenidia
of the unionid mussel Pyganodon cataracta.
The number, shape and relative length of ctenidia
to succeeding tergite was noted.
cancellata is not able to tolerate silt and clay because of ctenidia
obstruction, and reported two exceptions to this: the bivalves of the families Lucinidae and Tellinidae, represented in localities B and C by Codakia orbicularis.
Giant clam ctenidia
or gills were examined for histological abnormalities.
In Nucula, the protobranch gill closely resembles the ctenidia
of prosobranch gastropods, because both consist of a series of leaflets along a gill axis (Yonge, 1947).
Such resolution may also help account for adaptive adjustments in efficiencies of retention on the ctenidia
(Stenton-Dozey & Brown 1992, Barille et al.
fluminea are held in the inner demibranches of the ctenidia
(gills) after release from the gonads, then fertilized, and embryos are brooded in the same structure.