. Bonner zoologische Monographien. Zoology. 85 because a tendon bone 'ectopterygoid' is absent in nematogenyids and ictalurids (see below), and probably in thypsidorids; therefore, the presence of the 'ectopterygoid' type 1 is a neoformation found in some 'pimelodids', 'bagrids', and ariids. Opercle and preopercle I will comment here on the opercular bones, because of their relationship to the Suspen- sorium. The opercle in trichomycterines has two articulations: the dorsal one with the hyoman- dibula, and a ventral articulation, where an opercular process or knob fits in a concave articular s
. Bonner zoologische Monographien. Zoology. 85 because a tendon bone 'ectopterygoid' is absent in nematogenyids and ictalurids (see below), and probably in thypsidorids; therefore, the presence of the 'ectopterygoid' type 1 is a neoformation found in some 'pimelodids', 'bagrids', and ariids. Opercle and preopercle I will comment here on the opercular bones, because of their relationship to the Suspen- sorium. The opercle in trichomycterines has two articulations: the dorsal one with the hyoman- dibula, and a ventral articulation, where an opercular process or knob fits in a concave articular surface of the preopercle (Arratia 1990b: Fig. 2B). This feature is interesting, because this is a semimovable articulation produced between two dermal bones. This. : Preopercle and quadrate, lateral view. — A: Amia calva (disarticulated specimen; KU 21338); B: Elops saurus (225 mm standard length; KU 3053); C: Chanos chanos (neurocranium 148 mm in length; CAS-SU 35075); D: Diplomystes nahuelbutaensis (disarticulated specimen; BMNH 1867-10-2:22). Pop: preopercle; q: quadrate; sy: Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Bonn, Zoologisches Forschungsinstitut und Museum Alexander Koenig
Size: 1592px × 1569px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodiversity, booksubjectzoology
