Captures per encounter were also estimated for a trochophore
This study describes, in detail, the development from the embryonic stage to the early juvenile stage in Panopea globosa, with the formation of trochophore
larvae occurring 17.5 h (94.8 [micro]m) after fertilization.
The ECM receptor glypican-LP (CGI_10016108) is a major heparan sulfate proteoglycan and together with syndecan-LP (CGI_10004071) is highly expressed from the early stages until the early trochophore
For AZA and DELTA treatments the abundance of trochophore
larvae was higher compared to the control and remained high as the concentrations increased (up to 68 [+ or -] 18% for the 100 [micro]g [L.sup.-1] dose and 66 [+ or -] 7% for the 1000 [micro]g [L.sup.-1], respectively).
larvae were observed between eight and ten hours later.
The fertilized egg then develops into a larva called a trochophore
. The length of time a larva can survive in the water depends on its physiology - that is, how much lipid it has and how quickly it metabolizes this stored energy.
Many marine invertebrate groups with different adult forms have similar larvae (such as the trochophore
larva of mollusks and annelids, or the pluteus larva of sea urchins and brittle stars), and these similar larval forms are usually considered to be examples of either convergent evolution by natural selection or functional constraints on the evolution of early stages in development (Jagersten 1972; Strathmann 1988; Raff and Kaufman 1991; Wray 1992, 1995).
The authors described the embryonic development of the species obtaining trochophore
larvae (size 58 [+ or -] 0.4 [micro]m) between 10-12 h and larvae "D" (size 67.9 [+ or -] 2.3 [micro]m) between 22-24 h after fertilization.
Namely, it begins with fertilization and spiral cleavage but is then followed by extracapsular development of free-swimming trochophore
larvae, appearing 6 hours after fertilization and existing for a total of 32 hours before entering the next veliger larval stage (Sprang.
The earliest actively swimming trochophore
appeared from 12.5 hpf and had a large preoral lobe destined to develop into the velum (Fig.
A typical bivalve usually discharges gametes into the water and externally fertilized eggs develop into free-swimming trochophore
, then veliger larvae (Barnes 1968).
Larval development of both hybrid strains progressed in a manner typical of tridacnines, with larvae progressing through trochophore
, veliger, and pediveliger stages before metamorphosing into juvenile clams (Fig.