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Table 1 Results of the histological examination of eosauropterygian taxa

From: Evolutionary implications of the divergent long bone histologies of Nothosaurus and Pistosaurus(Sauropterygia, Triassic)

Taxon Collection number Bone type Type of section Bone tissue type Number of growth cycles Ontogenetic stage Medullary Index (%) Histological specialization
N. marchicus/ N. winterswijkensis MfN R 174-2 Humerus ts of proximal shaft lzb 7 Adult 42.5 Some osteosclerosis
N. mirabilis SIPB R 54/2 Humerus dts, lts of proximal head, 9 ps lzb 10 Adult 63.8 Much reduced cortex
N. mirabilis SIPB R 50/2 Femur dts lzb 9 Subadult 63.0 None
N. mirabilis SIPB R 54/1 Femur dts, lts of proximal head, 8 ps lzb 8 Adult 42.5 Some osteosclerosis
N. mirabilis SIPB R 50/1 Femur dts lzb 9 Subadult 32.9 Osteosclerosis
N. giganteus SIPB R 45 Humerus dts lzb EFS Fully grown 58.8 Much reduced cortex
N. giganteus SIPB R 53 Humerus dts lzb EFS Fully grown 77.4 Much reduced cortex
N. giganteus SIPB R 40 Humerus ts of proximal shaft lzb / Adult 74.7 Much reduced cortex
N. giganteus MHI 1903 Humerus 2 mts lzb 8 / / /
N. giganteus SIPB R 49 Femur dts lzb 7 Subadult 75.8 Much reduced cortex
Nothosaurus sp. indet. MHI 1906 Humerus dts lzb 3 Juvenile 35.0 Osteosclerosis
Nothosaurus sp. indet. MHI 633 Humerus dts flb 3 Juvenile 26.9 Thick cortex of flb
Nothosaurus sp. indet. SMNS 84856 Femur dts lzb 10 Adult 27.8 Osteosclerosis
Pistosaurus longaevus SIPB R 46 Humerus dts flb 5 Adult 6.7 Thick cortex of flb
Pistosaurus longaevus SMNS 84825 Humerus dts flb 7 Adult 5.0 Thick cortex of flb
Pistosaurus longaevus SIPB R 74 Femur dts lzb 8 Subadult or adult 65.8 Some osteosclerosis
Plesiosaurus dolichodeirus SIPB R 90 Femur dts flb EFS Fully grown 35.0 Haversian remodeling
  1. Overview of the sampled taxa, long bones, and histological observations. A low MI means a small medullary region. Abbreviations: dts diaphyseal thin section, EFS external fundamental system, flb fibrolamellar bone, lts longitudinal thin section, lzb lamellar zonal bone, mts metaphyseal thin section, ps polished sections, ts thin section, / absent or growth marks not identifiable.