crepis

crepis (noun; plural crepides; Greek krepis, base): 1. (Arthropoda: Insecta) In Scarabaeoidea larvae, a thinly sclerotized, anteriorly concave, median cross bar of the haptolachus, usually asymmetrical and indicated by a fine line when present; a transverse, strongly bowed bar.

2. (Porifera) An ordinary minute monaxon, triradiate or tetraxon spicule on which layers of silica have been irregularly deposited.