Table 1.
Species and specimens examined.
Table 2.
Vertebral laminae present in non-lacertid Squamata, showing occurrence in presacral, sacral, and caudal vertebrae.
Table 3.
Vertebral laminae present in lacertid Squamata, showing occurrence in presacral, sacral, and caudal vertebrae.
Fig 1.
Laminae in presacral vertebrae of Lacertini.
Hypothetical dorsal vertebra of a lacertid in dorsal (A), anterior (B), left lateral (C) and posterior (D) view (based on Lacerta trilineata MDHC 240), with the positions of the occurring laminae indicated. Scale bar = 1 mm. Abb.: nc, neural canal; ns, neural spine; poz, postzygapophysis; prz, prezygapophysis; syn, synapophysis; zya, zygantrum; zys, zygosphene.
Fig 2.
Size-related change in development of the PCYL.
Dorsal vertebrae of Lacerta trilineata MDHC 240 (A) and Lacerta strigata MDHC 304 (B) in right lateral view. Arrowheads indicate the presence (A) and absence (B) of the PCYL in large (A) and small (B) lacertines. Vertebrae scaled to the same centrum length. Scale bars = 1 mm. Abb.: nc, neural canal; ns, neural spine; poz, postzygapophysis; prz, prezygapophysis; syn, synapophysis.
Fig 3.
CPRL and POSL in lacertine presacral vertebrae.
Dorsal vertebra of Lacerta trilineata MDHC 240, in anterior (A), left lateral (B) and posterior (C) view. Arrowheads indicate the CPRL with a crest (A, B), and the ridge-like POSL (C). Scale bar = 1 mm. Abb.: ns, neural spine; poz, postzygapophysis; prz, prezygapophysis; syn, synapophysis.
Fig 4.
Different morphologies of the TPRL in dorsal vertebrae of Lacertini (black lines): Lacerta trilineata MDHC 240 (A), L. strigata MDHC 304 (B), and Phoenicolacerta troodica MDHC 318 (C) in dorsal view. Note the anterior projections in A, the narrow midline incision in B, and the regularly subtriangular TPRL in C. Vertebrae scaled to the same neural arch length. Scale bars = 1 mm. Abb.: ns, neural spine; poz, postzygapophysis; prz, prezygapophysis; zys, zygosphene.
Fig 5.
Dorsal vertebrae of Phoenicolacerta troodica MDHC 318 (A) and Lacerta trilineata MDHC 240 (B) in right lateral view, showing reduced (dashed line, A) and well-developed (B) PPRLs and PRSLs. Vertebrae scaled to the same centrum length. Scale bars = 1 mm. Abb.: PPRL, postzygoprezygapophyseal lamina; PRSL, prespinal lamina.
Fig 6.
SPRL in the axis of Lacerta bilineata MDHC 15 in anterior view (arrow).
Note that the left and right SPRL do not conjoin below the spine summit. Scale bar = 1 mm. Abb.: ic, intercentrum; op, odontoid process; poz, postzygapophysis; prz, prezygapophysis; syn, synapophysis.
Fig 7.
Cervical vertebra of Lacerta trilineata MDHC 356 in left lateral (A) and posterior (B) view, showing dorsal incision of the CPOL (arrowhead, A), and the dorsal fading of the SPOL on the neural spine process (arrowhead, B). The neural spine summit is damaged. Scale bar = 1 mm. Abb.: poz, postzygapophysis; syn, synapophysis.
Fig 8.
Laminae in sacral vertebrae of Lacertini.
Hypothetical sacral vertebra 2 of a lacertid in dorsal (A), anterior (B), left lateral (C) and posterior (D) view (based on Lacerta trilineata MDHC 356), with the positions of the occurring laminae indicated. Asterisks mark the laminae only occurring in sacral and anterior caudal vertebrae of Lacertini. Scale bar = 2 mm. Abb.: nc, neural canal; ns, neural spine; poz, postzygapophysis; prz, prezygapophysis; sr, sacral rib; zya, zygantrum; zys, zygosphene.
Fig 9.
TPOL (arrow) in posterior autotomic caudal vertebra of Podarcis wagleriana MDHC 390 in posterior view.
Scale bar = 1 mm. Abb.: CPOL, centropostzygapophyseal lamina; poz, postzygapophysis; SPOL, spinopostzygapophyseal lamina.
Fig 10.
Size-related change of development of the PCYL.
Cervical vertebrae of the skeletally immature Lacerta bilineata MDHC 48 (separate left neural arch, A), and the mature L. trilineata MDHC 356 in left lateral view. Note the well-developed (arrowhead, B) PCYL in the large, mature specimen, in contrast to the small, immature specimen, where no PCYL occurs (A). The neural spine summit of MDHC 356 is damaged. Vertebrae are scaled to the same neural arch length. Scale bars = 1 mm. Abb.: poz, postzygapophysis; syn, synapophysis.