Fig 1.
Muscular, fleshy, bone or cartilage elements of the tongue in extant archosaurs and outgroups.
Table 1.
Extant specimens and staining protocol applied.
Fig 2.
DiceCT imaging of the head of Alligator mississippiensis.
Individual cross-sections (A-D) from cranial to caudal region with targeted muscular and bony elements colored and labeled. Abbreviations: bh, basihyal; cb, ceratobranchial; ephc, episterno-hyoid muscular complex; lar, larynx; mbm, M. branchiomandibularis; mhy, M. hyoglossus; mge, M. genioglossus; tg, tongue.
Fig 3.
DiceCT imaging of the head of Dromaius novaehollandiae.
Individual cross-sections (A-D) from cranial to caudal region with targeted muscular and bony elements colored and labeled. Abbreviations: lar, larynx; mbm, M. branchiomandibularis; mcg, M. ceratoglossus; mge, M. genioglossus; mhys, M. hypoglossus; msh, M. stylohyoideus and M. serpihyoideus; mtl, M. tracheolateralis.
Fig 4.
DiceCT imaging of the head of Nothoprocta perdicaria.
Individual cross-sections (A-D) from cranial to caudal region with targeted muscular and bony elements colored and labeled. Abbreviations: lar, larynx; mbm, M. branchiomandibularis; mcg, M. ceratoglossus; mge, M. genioglossus; mhys, M. hypoglossus; msh, M. stylohyoideus and M. serpihyoideus; mtl, M. tracheolateralis; md, mandible.
Fig 5.
DiceCT imaging of the head of Phasianus colchicus.
Individual cross-sections (A-D) from cranial to caudal region provided with targeted muscular and bony elements colored and labeled. Abbreviations: bh, basihyal; cb, ceratobranchial; ep, epibranchial; mbm, M. branchiomandibularis; mcg, M. ceratoglossus; mch, M. cricohyoideus; msh, M. stylohyoideus and M. serpihyoideus; md, mandible.
Fig 6.
Hyoid remains in extinct archosaurs.
(A)Alligator prenasalis, pterosaurs (B)Liaoxipterus brachycephalus and (C)Ludodactylus sibbicki, (D)basal ornithischian Jeholosaurus shangyuanensis, (E)tyrannosaur Yutyrannus huali (F) Sinosauropteryx prima.
Fig 7.
(A) Microraptor zhaoianus, (B)Confuciusornis sp., (C)Enantiornithine sp., (D)Hongshanornis longicresta. The blue arrow indicates the ossified basihyal in Confuciusornis and Hongshanornis; it was also observed in one specimen of Microraptor. The green arrow indicates the phylogenetically earliest epibranchial [15]. See S1 Table for specimen numbers and supplemental references for published specimens.
Table 2.
Scanning parameters for extant specimens.
Fig 8.
The evolution of the tongue in Archosauria.
Fig 9.
Episterno-hyoid and M. coracohyoideus muscle in Alligator mississippiensis and proposed homologous muscles in Aythya americana.
(A)(B)Alligator mississippiensis (TMM M-12053), (C)(D)the homologous M. sternotrachealis in Aythya americana (TMM M-12682). Abbreviations: ephc, episterno-hyoid complex; epis or inter, episternum or the interclavicle; fur-furcula; mclh, M. cleidohyoideus (in Aythya); mcoh, M. coracohyoideus (in Alligator); tra, trachea.
Fig 10.
The M. branchiomandubularis (arrows) in birds and Alligator.
(A)Rhea americana (USNM 615363), (B)Dromaius novaehollandiae (TMM M-14235), (C) Nothura maculosa (USNM 631209), (D)Megapodius pritchardii (USNM 319640), (E) Phasianus colchicus (TMM M-12000), (F)Alligator mississippiensis (TNHC specimen). The two portions of the muscle are indicated in Galliformes: ‘M. branchiomandubularis cranialis’ (mbm_a) and ‘caudalis’ (mbm_p).
Fig 11.
M. intermandibularis cranialis in birds and Alligator.
(A)Rhea americana (USNM 615363), (B)Nothura maculosa (USNM 631209), (C)Dromaius novaehollandiae (TMM M-14235), (D)Struthio camelus (TMM M-14237), (E)Alligator mississippiensis (TNHC specimen) and (F)Phasianus colchicus (TMM M-12000). The muscle was indicated by black arrow.
Fig 12.
Episterno-hyoid and M. coracohyoideus muscle in Alligator and proposed homologous muscles in birds.
(A)(B)Alligator mississippiensis (TMM M-12053), (C)(D)the homologous M. sternotrachealis in Aythya americana (TMM M-12682). (E)(F) show the M. tracheolateralis in Aythya americana (USNM 643741) and Rhea americana (USNM 615363) respectively; (G)(H)(I) show M. cricohyoideus in Nothura machulosa (USNM 631210), Megapodius pritchardii (USNM 319640) and Aythya americana (USNM 643741) respectively Abbreviations: ephc, episterno-hyoid complex; mch, M. cricohyoideus; mclh, M. cleidohyoideus; mtl, M. tracheolateralis, and mstt, M. sternotrachealis.
Fig 13.
The position of the laryngeal opening in birds and Alligator.
Laryngeal opening is indicated by the red circle. (A)Alligator mississippiensis (TNHC specimen), (B)Dromaius novaehollandiae (TMM M-14236); (C)Nothura maculosa (USNM 631210), (D)Phasianus colchicums (TMM M-12001).