ambulacrum

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ambulacrum

(ăm′byə-lăk′rəm, -lā′krəm)
n. pl. ambu·lacra (-lăk′rə, -lā′krə)
One of the five radial areas on the undersurface of the starfish and similar echinoderms, from which the tube feet are protruded and withdrawn.

am′bu·lac′ral adj.

ambulacrum

one of the five radial bands on which tube feet occur on the outside surfaces of ECHINODERMS.
References in periodicals archive ?
The plates in the anterior paired ambulacra (areas II and IV) averaged 25.
The suture between the plates in ambulacra I and V (the I-V suture) is typically the longest.
parma, the anterior oral ambulacra have more plates, but the posterior oral ambulacra have larger plates (fig.
There is little variation in relative plate size, and the variation that does exist is not strongly correlated with the longitudinal position of the ambulacra.
In other northern Pacific sand dollars, the anterior and posterior ambulacra (and interambulacra) develop at different rates.