. Bonner zoologische Monographien. Zoology. 31. : Anterior part of the Suspensorium and maxilla of Hoplias malabaricus, ventral view (100 mm standard length; KU 13636). : articular facet for lateral ethmoid; apa: au- topalatine; Mx: maxilla; Tp: toothplate (dotted). in position. The autopalatine is dorsal to the entopterygoid; these bones do not ar- ticulate and are not linked by a ligament. In Hoplias, the toothplate is attached by a ligament to the ventral part of the vomer and dorsal part of the autopalatine. This plate was called accessory ectopterygoid tooth plate by Weitzman (
. Bonner zoologische Monographien. Zoology. 31. : Anterior part of the Suspensorium and maxilla of Hoplias malabaricus, ventral view (100 mm standard length; KU 13636). : articular facet for lateral ethmoid; apa: au- topalatine; Mx: maxilla; Tp: toothplate (dotted). in position. The autopalatine is dorsal to the entopterygoid; these bones do not ar- ticulate and are not linked by a ligament. In Hoplias, the toothplate is attached by a ligament to the ventral part of the vomer and dorsal part of the autopalatine. This plate was called accessory ectopterygoid tooth plate by Weitzman (1964). It is anterior to but not associated with the ectopterygoid; the numerous, conical teeth face their antimeres medially; however, the toothplates are not sutured to each other. This small dentate bone is not a dermopalatine because this element is missing in primitive ostariophysans; therefore, this element is considered here to be a new formation. The name toothplate is used to avoid confusion with either the dermopalatine, or the subautopalatine toothplate of catfishes. Gymnotoids The Suspensorium of gymnotoids has been extensively illustrated by Chardon & de la Hoz (1974), who proposed a classification of the group based on the Suspensorium. Here I will only address a few points. The anterior part of the palatoquadrate — the pars autopalatina — does not differen- tiate into an autopalatine in most gymnoids (Fig. 12A); however, it does in Hypopomus (Fig. 12B, D). In Hypopomus, anteriorly the Suspensorium is connected to the premax- illa by a ligament; laterally, the pars autopalatine articulates with the maxilla. A small, round cartilage between the autopalatine and lateral ethmoid is present in Hypopomus. This cartilage is free. The ectopterygoid is absent. The large entopterygoid occupies the position of the ectopterygoid of other teleosts. Among gymnotoids, the dorsal projec- tion of the entopterygoid (Fig. 12A, B) exhibits different degrees of development. T
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