Galahadosuchus

Galahadosuchus Temporal range: Late Triassic Carnian–Rhaetian PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Archosauria
Clade:	Pseudosuchia
Clade:	Crocodylomorpha
Family:	† Saltoposuchidae
Genus:	† Galahadosuchus Bodenham et al., 2026
Species:	†G. jonesi
Binomial name
†Galahadosuchus jonesi Bodenham et al., 2026

Galahadosuchus is an extinct genus of saltoposuchid crocodylomorph from the Late Triassic fissure deposits of Cromhall Quarry in the United Kingdom. It is known from a partial postcranial skeleton including most of the hindlimbs, an almost complete forelimb and a series of tail vertebrae.

History and naming

The holotype specimen of Galahadosuchus, NHMUK PV R 10002, was recovered by Ron Croucher in 1969 from site 1 of the fissure deposits at Cromhall Quarry in Gloucestershire, southwest England. The specimen is preserved across two slabs and consists of a partially articulated postcranial skeleton including parts of the tail and hindlimbs, a nearly complete right forelimb, several isolated elements such as osteoderms, ribs and non-caudal vertebrae as well as the remains of a rhynchocephalian reptile. The Cromhall Quarry, also known as Slickstones Quarry, is one of several Late Triassic to Early Jurassic fissure fill deposits in the Bristol Channel area that have previously yielded crocodylomorph remains including those of the saltoposuchid Terrestrisuchus (from the Pant-y-Ffynnon Quarry). Many of these remains have at times either been compared to Terrestrisuchus or assigned to the genus wholesale, though later revisions showed them to frequently be too fragmentary for such specific referrals. In one such case specimen NHMUK PV R 10002 and some other disarticulated remains from other sites (numbered 1-5 and 7) in the Cromhall Quarry were referred to Terrestrisuchus by Fraser and colleagues in 2002, who regarded them to represent two different morphs of the genus, both of which were deemed different from the type material from Pant-y-Ffynnon. ^[1]

While Fraser and colleagues did not describe the material nor provide a concrete reasoning for their assignments and distinctions, a brief description of the material was published by R. C. Allen in a PhD thesis in 2010 partially agreeding with their assertion. In this thesis Allen argued that while NHMUK PV R 10002 was referrable to Terrestrisuchus gracilis, the remains from the other Cromhall Quarry sites held at the Virginia Museum of Natural History were not. Another study dealing with these fossils was published in 2023, in which Spiekman and colleagues held that contrary to the works of Fraser and Allen NHMUK PV R 10002 was not assignable to Terrestrisuchus, though the team deamed a full redescription to be beyond the scope of their work. ^[1]

The name Galahadosuchus derives from Sir Galahad of Arthurian legend and is a play on words. As explained by Bodenham and colleagues, Galahad is renown for being upright in a moral sense in the myth, while Galahadosuchus is also upright, albeit in relation to its posture. The ending of the genus name "suchus" is derived from the Greek word for crocodile as frequently used in the scientific names of fossil pseudosuchians. The species name "jonesi" was chosen in honor of David Rhys Jones, a teacher at the Ysgol Uwchradd Aberteifi school in Wales, who was an inspirational figure to lead author Ewan H. Bodenham, supporting student′s pursuit of science. ^[1]

Phylogeny

Both phylogenetic analysis run by Bodenham and colleagues recovered Galahadosuchus as a member of the family Saltoposuchidae and in both instances it was found to be the sister taxon of Terrestrisuchus from the nearby Pant-y-Ffynnon Quarry. Equal weighting of phylogenetic characters recovers a family resembling the resuls of Spiekman et al. (2023), who's dataset the analysis was based on. In the resulting tree the immediate sister form to both Galahadosuchus and Terrestrisuchus is Litargosuchus with Saltoposuchus as the family's basalmost member. Extended implied weighting meanwhile recovered different results based on the used k-value. A k-value of 13-15 results in the same topology as under equal weights, but a k-value of 3-12 changes the resulting tree in minor ways. While the close ties between Galahadosuchus and Terrestrisuchus are retained, Litargosuchus is instead recovered as a more derived crocodylomorph while Saltoposuchus is moved closer to the former within the family. It's place as basalmost saltoposuchid is taken by Hesperosuchus . ^[1]

Stagonolepis Gracilisuchus Saurosuchus Postosuchus CM 73372 Carnufex Redondavenator Erpetosuchus Trialestes Pseudohesperosuchus Saltoposuchus Litargosuchus Terrestrisuchus Galahadosuchus Hesperosuchus Dromicosuchus Kayentasuchus Sphenosuchus Dibothrosuchus Junggarsuchus Almadasuchus Macelognathus Hallopus Crocodyliformes

Stagonolepis Gracilisuchus Saurosuchus Postosuchus CM 73372 Carnufex Redondavenator Erpetosuchus Trialestes Pseudohesperosuchus Hesperosuchus Saltoposuchus Terrestrisuchus Galahadosuchus Dromicosuchus Kayentasuchus Litargosuchus Sphenosuchus Dibothrosuchus Junggarsuchus Almadasuchus Macelognathus Hallopus Crocodyliformes

References

1. Bodenham, E. H.; Spiekman, S. N. F.; Maidment, S. C. R.; Upchurch, P.; Mannion, P. D. (2026). "A second species of non-crocodyliform crocodylomorph from the Late Triassic fissure deposits of southwestern UK: Implications for locomotory ecological diversity in Saltoposuchidae". The Anatomical Record. doi: 10.1002/ar.70162 .