gnathobase Zool.
(ˈneɪθəʊbeɪs)
[f. gnatho- + base n.1]
A process developed from the lower part of a segmented limb in certain arthropods, modified to bite or crush food. Hence gnathoˈbasic a.
| 1881 E. R. Lankester in Q. Jrnl. Micr. Sci. Apr. 348 Of the six endites the proximal is somewhat isolated and pushed towards the middle line... It is a jaw process, and may be spoken of as the ‘gnathobase’. 1902 ― in Encycl. Brit. XXV. 695/1 The five pairs of appendages of the post-oral somites of the head or prosoma thus constituted all primitively carry gnathobasic projections on their coxal joints, which act as hemignaths; in the more specialized forms the mandibular gnathobases cease to develop. 1904 W. T. Calman in Ann. & Mag. Nat. Hist. Feb. 155 The double series of epipodial lamellæ, the segmentation of the thoracic limbs, the double gnathobasic lobes of the first pair. 1932 Borradaile & Potts Invertebrata x. 274 Some of the evidence suggests an archetype [arthropod] with a nine-segmented axis bearing on the median side of the first segment a biting process (gnathobase). 1964 New Scientist 13 Aug. 365/2 The mandibles themselves may either derive from the basal part of a segmented limb (the gnathobase) or from a whole jointed limb. |