A large Middle Devonian eubrachythoracid ‘placoderm’ (Arthrodira) jaw from northern Gondwana

Swiss Journal of Palaeontology

Table 2 Morphological character matrix of posterior superognathals of eubrachythoracids including information on the age and locality of the material

	Age	Locality	1	2	3	4	5	6	7	8	9	Refs.
Compagopiscis croucheri	Frasnian	Australia	1?	1	0	0	1	1	0	0	1	Gardiner and Miles (1994)
Coccosteus cuspidatus	Eifelian–Givetian	UK (and other)	0	1	1	0	0–1	1	0–1	0	1	Miles and Westoll (1968)
Plourdosteus canadensis	Frasnian	Poland	0	1	1?	0	1	2–1	1	1	0	Ørvig (1980)
Mcnamaraspis kaprios	Frasnian	Australia	0	1	0	0	0	1	1	1	0	Long (1995)
Eastmanosteus calliaspis	Frasnian	Australia	1	1	0	0	0	1	0	0	1	Dennis-Bryan (1987)
Harrytoombsia elegans	Frasnian	Australia	1?	1	1	0	1	1	0	0	0	Miles and Dennis-Bryan (1979)
Torosteus pulchellus	Givetian–Frasnian	Australia	1?	1	0	0	1	1	0	0	1	Gardiner and Miles (1990)
Leptodontichthys ziregensis	Givetian	Morocco	0	1	1	1	0	2	1	1	0	This paper

Character 1 is the shape of the PSG (0: sub-rectangular, 1: triangular). Character 2 is the only character mentioned in the arthrodire character matrix of previous papers (e.g., King et al. 2016), which describes the dorsal process of the gnathal element (0: absent, 1: large, 2: small). Character 3 is the shape of the dorsal process (0: elongate, 1: short). Character 4 marks the ventral depression in the aforementioned dorsal process (0: absent, 1: present). Character 5 refers to a mesial tooth row (0: absent, 1: present). Character 6 describes tooth orientation (0: no teeth, 1: pointing downwards, 2: near parallel to the occlusion). Character 7 refers to the presence of a smooth ventral margin anterior to the lateral process (0: absent, 1: present) and character 8 anterior to the posterior process (0: absent, 1: present), both in late ontogenetic stages. Character 9 describes the height of the PSG (0: broad, 1: narrow). Uncertainties are marked by with “?”