| Basic info | Taxonomic history | Classification | Included Taxa |
| Morphology | Ecology and taphonomy | External Literature Search | Age range and collections |
Pleurosternon bullockii
Discussion
The type specimen was originally erroneously described by Owen (1842, 1850) as from the London Clay of Sheppey. It was correctly localised by Lydekker and Boulenger (1887) but there are no precise locality details. [From Milner 2004, p. 1448]
Taxonomy
Platemys bullockii was named by Owen (1842). Its type specimen is BMNH R911, a partial shell (a large complete plastron), and it is a 3D body fossil. Its type locality is Swanage/Purbeck (BMNH) [Bullock's Museum], which is in a Berriasian fluvial-lacustrine limestone in the United Kingdom.
It was recombined as Digerrhum bullockii by Cope (1870); it was recombined as Pleurosternum bullockii by Lydekker and Boulenger (1887), Lydekker (1889); it was recombined as Pleurosternum bullocki by Lydekker (1889), Delair (1958); it was recombined as Pleurosternon bullockii by Milner (2004), Pérez-García et al. (2008), Pérez-García and Ortega (2011), Perea et al. (2014), Joyce and Anquetin (2019), Guerrero and Pérez-García (2020), Guerrero and Pérez-García (2021), Allain et al. (2022).
It was recombined as Digerrhum bullockii by Cope (1870); it was recombined as Pleurosternum bullockii by Lydekker and Boulenger (1887), Lydekker (1889); it was recombined as Pleurosternum bullocki by Lydekker (1889), Delair (1958); it was recombined as Pleurosternon bullockii by Milner (2004), Pérez-García et al. (2008), Pérez-García and Ortega (2011), Perea et al. (2014), Joyce and Anquetin (2019), Guerrero and Pérez-García (2020), Guerrero and Pérez-García (2021), Allain et al. (2022).
Sister species lacking formal opinion data
Synonyms
|
Synonymy list
| Year | Name and author |
|---|---|
| 1842 | Platemys bullockii Owen p. 164 |
| 1853 | Pleurosternum emarginatum Owen |
| 1853 | Pleurosternon concinnum Owen p. 3 figs. plates 2-3 |
| 1853 | Pleurosternon emarginatum Owen p. 6 figs. plate 4 |
| 1853 | Pleurosternon ovatum Owen p. 8 figs. plate 7 |
| 1869 | Pleurosternon sedgwicki Seeley p. 86 |
| 1869 | Pleurosternon vansittarti Seeley p. 86 |
| 1869 | Pleurosternon oweni Seeley p. 87 |
| 1870 | Digerrhum bullockii Cope p. 156 |
| 1870 | Megasternon koenigii Gray |
| 1887 | Pleurosternum bullockii Lydekker and Boulenger p. 271 |
| 1887 | Plesiochelys emarginata Lydekker and Boulenger p. 272 |
| 1889 | Pleurosternum bullocki Lydekker pp. 206-215 |
| 1889 | Pleurosternum portlandicum Lydekker pp. 215-216 fig. 47 |
| 1889 | Hylaeochelys emarginatum Lydekker p. 514 |
| 1889 | Pleurosternum bullockii Lydekker pp. 514-515 |
| 1958 | Pleurosternum bullocki Delair p. 48 |
| 1958 | Pleurosternum portlandicum Delair p. 48 |
| 1958 | Hylaeochelys emarginata Delair p. 52 |
| 1975 | Mesochelys durlstonensis Evans and Kemp p. 26 figs. pls 4–5, text-figs 1–9 |
| 2004 | Pleurosternon bullockii Milner p. 1447 figs. Text-figs 3–4, 5A, 6, 7A |
| 2008 | Pleurosternon bullockii Pérez-García et al. |
| 2011 | Pleurosternon bullockii Pérez-García and Ortega |
| 2014 | Pleurosternon bullockii Perea et al. |
| 2019 | Pleurosternon bullockii Joyce and Anquetin |
| 2020 | Pleurosternon bullockii Guerrero and Pérez-García p. 3 |
| 2021 | Pleurosternon bullockii Guerrero and Pérez-García |
| 2022 | Pleurosternon bullockii Allain et al. |
Is something missing? Join the Paleobiology Database and enter the data
|
|
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
†Pleurosternon bullockii Owen 1842
show all | hide all
Invalid names: Megasternon koenigii Gray 1870 [synonym], Mesochelys durlstonensis Evans and Kemp 1975 [synonym], Pleurosternon concinnum Owen 1853 [synonym], Pleurosternon emarginatum Owen 1853 [synonym], Pleurosternon ovatum Owen 1853 [synonym], Pleurosternon oweni Seeley 1869 [synonym], Pleurosternon sedgwicki Seeley 1869 [synonym], Pleurosternon vansittarti Seeley 1869 [synonym], Pleurosternum portlandicum Lydekker 1889 [synonym]
Diagnosis
| Reference | Diagnosis | |
|---|---|---|
| A. R. Milner 2004 | Species of Pleurosternon in which entoplastron is wider than long, and intergular shield is shield-shaped with five straight edges (contra the Portlandian P. portlandicum in which entoplastron width equals length and intergular shield is pyriform and narrow posteriorly). | |
| W. G. Joyce and J. Anquetin 2019 | Pleurosternon bullockii can be diagnosed as a paracryptodire by the full list of characters listed for that clade above. Pleurosternon bullockii can be differentiated from all other paracryptodires by symplesiomorphically lacking a midline contact of peripherals I (in contrast to Selenemys lusitanica and Compsemys spp.) and by having a midline contact of the mesoplastra (in contrast to Riodevemys inumbragigas and most baenids) and by apomorphically lacking a cervical (as in Selenemys lusitanica and Toremys cassiopeia), only a single gular, and an elongate skull with low labial ridges and narrow triturating surfaces. | |
| A. Guerrero and A. Pérez-García 2021 | Pleurosternon bullockii is distinguished from the other pleurosternids by an exclusive character combination: small, regular, and clearly defined pits on the outer shell surface (shared with Selenemys lusitanica); well-developed fine striations perpendicular to the plate margins (shared with Glyptops plicatulus, Dorsetochelys typocardium, Riodevemys inumbragigas, S. lusitanica, and Toremys cassiopeia); relatively wide shell with respect to its length (shared with Do. typocardium, G. plicatulus, S. lusitanica, and R. inumbragigas); absence of carapace sagittal keel (shared with Dinochelys whitei, G. plicatulus, R. inumbragigas, S. lusitanica, and T. cassiopeia); shallow to absent nuchal notch (shared with Dinochelys whitei, Glyptops plicatulus, Riodevemys inumbragigas, Selenemys lusitanica, and Toremys cassiopeia); absence of notched posterior carapace margin (shared with Di. whitei, Dorsetochelys typocardium, G. plicatulus, S. lusitanica, and T. cassiopeia); anterior nuchal edge constituting the anterior carapace rim (shared with Di. whitei, Do. typocardium, G. plicatulus, R. inumbragigas, and T. cassiopeia); width of the nuchal less than twice its maximum length (shared with G. plicatulus, R. inumbragigas, and T. cassiopeia); width of the posterior margin of the first peripheral about two times less than the anterior one (shared with Di. whitei); absence of a cervical scute (shared with S. lusitanica and T. cassiopeia); first to third vertebral scutes more than two times wider than pleural scutes (shared with Di. whitei), but less than three and a half times (shared with Do. typocardium, G. plicatulus, R. inumbragigas, S. lusitanica, and T. cassiopeia); fourth and fifth vertebrals less than two times wider than pleurals (shared with Do. typocardium, G. plicatulus, R. inumbragigas, S. lusitanica, and T. cassiopeia); first vertebral anterolaterally overlapping the first pair of peripherals (shared with Di. whitei, Do. typocardium, G. plicatulus, R. inumbragigas, and T. cassiopeia); first vertebral wider than the nuchal (shared with Di. whitei, Do. typocardium, G. plicatulus, and T. cassiopeia); first to third pleural scutes relatively long in relation to their width, being always longer than wide (shared with Di. whitei); first pair of marginal scutes 12 wider than long (shared with Di. whitei, Do. typocardium, G. plicatulus, R. inumbragigas, and T. cassiopeia); second pair of marginals reaching the first pair of costals (shared with R. inumbragigas and S. lusitanica); overlapping of the twelfth pair of marginals on the second suprapygal (shared with Do. typocardium, S. lusitanica, and T. cassiopeia); subrounded lateral and anterior margins of the anterior plastral lobe (shared with Do. typocardium, G. plicatulus, S. lusitanica, and T. cassiopeia); absence of well-developed gular protrusions (shared with Do. typocardium, G. plicatulus, R. inumbragigas, and S. lusitanica); presence of a well-developed visceral dorsal epiplastral process (shared with R. inumbragigas); sagittal contact between both mesoplastra, their medial length being similar to the lateral one (shared with Di. whitei, Do. typocardium, G. plicatulus, S. lusitanica, and T. cassiopeia); presence of an anal notch (shared with Do. typocardium and T. cassiopeia); anal scutes entirely situated on the xiphiplastra (shared with G. plicatulus, R. inumbragigas, S. lusitanica, and T. cassiopeia). In addition, P. bullockii shows an elongate skull, with low labial ridges an narrow triturating surfaces that differs from those of the few members of Pleurosternidae in which this skeletal element is known. |
Measurements
No measurements are available
|
|
||||
|
|||||
|
|
||||
| Source: c = class, subp = subphylum, uc = unranked clade | |||||
| References: Carroll 1988, Hendy et al. 2009 | |||||
Age range: base of the Late/Upper Tithonian to the top of the Late/Upper Berriasian or 150.80000 to 140.20000 Ma
Collections (9 total)
| Time interval | Ma | Country or state | Original ID and collection number |
|---|---|---|---|
| Tithonian | United Kingdom (England) | Pleurosternum portlandicum (127647) | |
| Tithonian | France (Nord-Pas-de-Calais) | Pleurosternum bullochi (53967) | |
| Late/Upper Tithonian | United Kingdom (England) | Pleurosternum portlandicum (119505) | |
| Late/Upper Berriasian | United Kingdom (England) | Mesochelys durlstonensis (129260) | |
| Middle Berriasian | United Kingdom (England) | Pleurosternon bullockii (72142) | |
| Berriasian | United Kingdom (England) | Platemys bullockii, Pleurosternon sedgwicki, Pleurosternon vansittarti, Pleurosternon oweni, Megasternon koenigii (type locality: 127482) Pleurosternon concinnum (127480) Pleurosternon ovatum, Pleurosternon emarginatum, Pleurosternum bullocki (127481) | |
| Berriasian | France (Poitou-Charentes) | Pleurosternidae indet. (142093) |