with a circle of cilia was observed near the posterior end (Fig.
A non-feeding pilidium with apparent prototroch and telotroch
This photographically well-documented research report describes the development of an unusual telotroch
(the free-swimming, re-colonizing stage) from a zooid that was broken-off from a spasmoneme-bearing, colonial, contractile, stalked Peritrich protozooan.
was incomplete ventrally where the neurotroch passed through it.
Most annelid larval forms, feeding or not, can be readily related to the trochophore ground plan, which Nielsen (2001, 2004) defined as a larva bearing an apical tuft, a preoral ciliated band derived from trochoblasts (prototroch), an adoral ciliary zone, and postoral metatroch, gastrotroch, and telotroch
, all of which bands consist of multiciliate cells with compound cilia.
The perianal part of the cirCumblas-toporal band became the telotroch
The muscular framework that will be used by the juvenile worm after metamorphosis is already in place (3), but swimming is powered by two bands of cilia, an anterior prototroch, and a posterior telotroch
Two days after oviposition the presumptive apical tuft and prototroch on the apical region, and the telotroch
at the caudal end of the ectodermal trunk, became evident (Figs.
Larvae emerge from the brood tube after approximately 8 days as many-segmented metatrochophores, each bearing a prototroch and telotroch
, the classic trochophore stage being bypassed.
Larvae also bear a midventral neurotroch, posterior to the mouth, and a telotroch
In metatrochophore larvae, distinct cells in the ciliary bands of the prototroch and telotroch
and isolated cells in the apical region of the prostomium and the rest of the body displayed RIM-1 binding, indicating that these cells possess PKC [ILLUSTRATION FOR FIGURE 6B OMITTED].
Estimates of cilium lengths from an arrested telotroch
ranged from 51 to 57 [[micro]meter] (median 53 [[micro]meter], n = 7).