Table 2 Mandibular muscles of adults of representative actinopterygian taxa, including the zebrafish. The nomenclature of the muscles shown in bold follows that of the present work, "ad. mand." meaning adductor mandibulae. In order to facilitate comparisons, in some cases certain names often used by other authors to designate a certain muscle/bundle are given in front of that muscle/bundle. Data compiled from evidence provided by developmental biology, comparative anatomy, functional morphology, palaeontology, experimental embryology and molecular biology, innervation and phylogeny (for more details, see text).
Intermandibularis posterior(*intermandibularis anterior and posterior plesiomorphically present in osteichthyans? See text) | Intermandibularis | Intermandibularis | Intermandibularis | Intermandibularis posterior | Intermandibularis posterior (*forming, together with interhyoideus, the protractor hyoideus) | Intermandibularis posterior (*see cell on the left) |
|---|---|---|---|---|---|---|
Probable plesiomorphic osteichthyan condition | Cladistia: Polypterus bichir (Bichir) | Chondrostei: Psephurus gladius (Chinese swordfish) | Ginglymodi: Lepisosteus osseus (Longnose gar) | Halecomorphi: Amia calva (Bowfin) | Teleostei – basal: Elops saurus (Ladyfish) | Teleostei – clupeocephalan: Danio rerio (Zebrafish) |
Intermandibularis anterior (*see cell above) | ----- | ----- | ----- | Intermandibularis anterior | Intermandibularis anterior | Intermandibularis anterior |
----- | ----- | ----- | ----- | ----- | Protractor hyoideus (*including intermandibularis posterior and interhyoideus; it is thus derived from both the mandibular and hyoid muscle plates) | Protractor hyoideus (*see cell on the left) |
Ad. mand. A3' | Ad. mand. A3' (ad. mand. of e.g. Lauder [69]) | ----- | Ad. mand. A3' (preorbitalis superficialis of e.g. Lauder [69]) | Ad. mand. A3' | ----- | ----- |
Ad. mand. A3" | Ad. mand .A3" (ad. mand. pterygoideus of e.g. Lauder [69]) | ----- | Ad. mand. A3" (preorbitalis profundus of e.g. Lauder [69]) | Ad. mand. A3" | ----- | ----- |
Ad. mand. A2 | Ad. mand. A2 (ad. mand. posterolateral of e.g. Lauder [69]) | Ad. mand. A2 (ad. mand. of e.g. Carroll and Wainwright [72]) | Ad. mand. A2 (ad. mand. posterolateral of e.g. Lauder [69]) | Ad. mand. A2 | Ad. mand. A2 | Ad. mand. A2 |
----- | ----- | ----- | Palatomandibularis minor and major | ----- | ----- | ----- |
----- | ----- | ----- | ----- | Levator maxillae superioris 3 and 4 | ----- | ----- |
----- | ----- | ----- | ----- | ----- | ----- | Ad. mand. A1-OST |
----- | ----- | ----- | ----- | ----- | ----- | Ad. mand. A0 |
Ad. mand. Aω | Ad. mand. Aω | ----- | ----- | Ad. mand. Aω | Ad. mand. Aω | Ad. mand. Aω |
Levator arcus palatini | Levator arcus palatini | Protractor hyomandibulae (*seemingly originated from the portion of the hyoid muscle plate from which originate the adductor arcus palatini and dilatator operculi of other actinopterygians) | Levator arcus palatini | Levator arcus palatini | Levator arcus palatini | Levator arcus palatini |
----- | Dilatator operculi | ----- (*dilatator operculi absent as a separate element, but see cell above) | Dilatator operculi | Dilatator operculi | Dilatator operculi | Dilatator operculi |