a.1.(Zool.) Of or pertaining to the lobe of the carapace of crabs covering the posterior branchiæ.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
Dorsal surface convex longitudinally, almost smooth, with few disconnected, fine transverse ridges on protogastric region; pair of mats of minute setae between rostrum and protogastric ridges; cervical grooves faint; metabranchial and adjacent regions with distinct long transverse ridges; two rounded, shallow depressions laterally in cardiac region.
The oyster was closely attached to the left side, covering 60 to 70% of the epibranchial surface and about 90% of the mesobranchial and metabranchial regions.