antirostrum

antirostrum

[‚an·tē′räs·trəm]
(invertebrate zoology)
The terminal segment of the appendages of certain mites.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
For the otolith shape first were located three natural marks; the antirostrum tip, the focus and the right posterior border of the otolith then two templates was cons-tructed based on these marks; one for the otoliths ventral part and another for the dorsal part.
Overall, the highest shape variation among areas occurred in the excisura ostii and antirostrum. Variations also occurred in the dorsal and ventral edges of the otolith.
tauricus is semicircular shape, which has a convex outer face and its margin is moderate serrations and has a well-defined rostrum and antirostrum. Results of this study indicate that Crimean barbel's otolith limits of lobes are clearly identified.
The ostium is funnel-like, it has a cisura; the rostrum is broad and the antirostrum is small and angled.
Discussion.--The saccular otolith of Pogonias stringeri shows a number of characters diagnostic of Sciaenidae, including: a strongly homosulcoid sulcus, with both the rostrum and antirostrum absent; a broad, flat, shallow ostium with a distinct postostial lobe; and a narrow and horizontal cauda with a curved posterior cauda.
Additionally, for the non-expert, a figure of a generalized otolith depicting the relevant terms (e.g., antirostrum, colliculum, cauda, excisura) would greatly help.
Three segments perpendicular to the length included the width through the primordium, segment CE, and CE subsegment C-C' (a measure of the gap between the rostrum and antirostrum [point C]).
fitchi shows a number of characters diagnostic of Sciaenidae including: a strongly homosulcoid sulcus, with both the rostrum and antirostrum absent; a broad, flat, shallow ostium with a distinct postostial lobe; and a narrow horizontal anterior cauda with a curved posterior cauda.
Otolith tracing began at the tip of the antirostrum, was directed manually across the base of the rostrum, and then the software traced the posterior portion of the otolith.
The sulcus is strongly homosulcoid with both the rostrum and antirostrum absent.