51813_Sturgeon biodioversity an.PDF

Figure 3.Jugal of representatives of all genera of Acipenseridae: The jugal defines the posteroventral margin of the orbit (top ...

the circumorbital series, docs not apply to the ante- rior process of the jugal of acipenserids. The ex- tended jugal braces the ...

Figure 5.Extrascapular bones of the posterior skull roof in †Chondrosteusand representatives of all genera of Acipenseridae: The ...

by tube bones independent of the skull roof Character5.Medianextrascapularbonepresent– (Grande & Bemis 1991). The infraorbit ...

Figure 7.The opercular series of †Chondrosteus,†Peipiaosteus,and representatives of all genera of Acipenseridae: †Chondrosteus(a ...

Character6.The rostralcanal archeslaterally–Aci- penseridae Rostral sensory canals extend ventromedially un- der the rostrum, bu ...

indications from Gardiner & Schaeffer 1989) are 1991) support the caudal fin, leaving a gap in the pe- apparently also strai ...

scapulocoracoid with the cardiac shield supporting the expanded coracoid shelf (see Character 14). The clavicle and cleithrum of ...

Figure 9.Left scapulocoracoid ofAcipenser brevirostrum(a) andScaphirhynchus platorynchus(b) in lateral and anterior views: The v ...

Character 13. Clavicle process interdigitates with the Character 15.SupracleithraI cartilage present–Aci- cleithrum-Acipenserida ...

Figure 10.Palatal complex of representatives of three genera of Acipenseridae: The palatal complex is a cartilaginous plate boun ...

tapers ventrally inHusoand all speciesAcipenser examined (Figure 11b, c) to a ventral position form- ing a flat edge in scaphirh ...

Character21.Anterior shelf protrudes from hypo- branchial one –Acipenseridae An anterodorsal shelf expands from hypobranchial on ...

used for prey processing opposite to the palatal consistent. Scaphirhynchines lack these scales complex (Character 18). (Charact ...

Figure 13.Ventral hyobranchial skeleton inPsephurusand representatives ofHusoandScaphirhynchus: The skeleton is shown in oral vi ...

basitrabecular process medially (Findeis 1993) is This morphology contrasts with the inferred ple- siomorphic condition of Pseph ...

Figure 15.Basitrabecular processes of representatives of all genera of Acipenseridae: Basitrabecular processes (btp) extend vent ...

Figure 16. Jaw joint of polyodontids and representatives of three genera of Acipenseridae: The jaw joint is shown with anterior ...

Figure 17. Ventral rostrum of Psephurusand representatives of three genera of Acipenseridae: The rostrum is thin and tapers in P ...

form a broad shield expanding anterior to the olfac- tory cavity (drb, Figure 18c, d). The dorsal rostral shield broadens in con ...