A new incisoscutid arthrodire is described from the Upper Devonian Gogo Formation of Western Australia as Gogosteus sarahae gen. et sp. nov. It is characterised by its narrow headshield with cheek unit firmly attached to skull roof, crushing gnathal plates, deep postnasal plates, elongate anterior lateral plate with deeply embayed postbranchial notch and squarely cut posterior margin, and fine dermal ornamentation. The family Incisoscutidae Denison 1984 is redefined to include Incisoscutum ritchiei Dennis & Miles 1981 and Gogosteus gen. nov., and the superfamily Incisoscutoidea nov. defined to include Incisoscutidae and Camuropiscidae.
- Incisoscutidae. arthrodire
- New species