Chaliminia musteloides (Bonaparte et al. 2001, Martinelli and Rougier 2007; Late Triassic, 215 mya; PVL 3857) is a close relative of Pachygenelus. Note the large dentary incisors and short premaxillary incisors.

Riograndia guaibensis (Bonaparte et al. 2001, Soares et al. 2011; Late Triassic, 215 mya) is a trithelodontid close to Pachygenelus, basal to mammaliaformes.

From the Soares et al. abstact: "Riograndia shows a suite of important anatomical features quite derived among the non-mammaliaform eucynodonts, such as the partial closure of the medial orbital wall and braincase, extensive secondary osseous palate, wide primary palate, basicranium with jugular foramen separated from the periphery of fenestra rotunda, narrow zygomatic arch and much reduced postdentary bones."

Bonaparte JF, Ferigolo J and Ribeiro AM 2001. A primitive Late Triassic 'ictidosaur' from Rio Grande Do Sul, Brazil. Palaeontology 44(4):623-635.

Martineli AG and Rougier GW 2007. On Chaliminia musteloides (Eucynodontia: Tritheledontidae) from the Late Triassic of Argentina, and a phylogeny of Ictidosauria. Journal of Vertebrate Paleontology 27( 2): 442-460

Soares MB, Schultz CL and Horn BLD 2011. New information on Riograndia guaibensis Bonaparte, Ferigolo & Ribeiro, 2001 (Eucynodontia, Tritheledontidae) from the Late Triassic of southern Brazil: anatomical and biostratigraphic implications. Anais da Academia Brasileira de Ciências. 83 (1): 329–354.

Watson DMS 1913. On a new cynodont from the Stormberg. Geological Magazine, new series, decade 5 10(4):145-148

wiki/Riograndia