Originally it was considered a basal ornithopod.
Andrzejewski, Winkler and Jacobs 2019 report,
“The new ornithopod, Convolosaurus marri gen. et sp. nov., is recovered outside of Iguanodontia, but forms a clade with Iguanodontia exclusive of Hypsilophodon foxii. The presence and morphology of four premaxillary teeth along with a combination of both basal and derived characters distinguish this taxon from all other ornithopods.”
the large reptile tree (LRT, 1419 taxa) nests Convolosaurus basal to the Agilisaurus + Stegoceras at the base of the Pachycephalosauria (dome-head dinos). All these taxa were included in the original paper, but they did not nest together. Andrzejewski, Winkler and Jacobs 2019 did not nest their cladogram on Chilesaurus and Daemonosaurus, two taxa missing from their cladogram. This may have played a part in the different tree topologies.
the LRT presently does not include Hypsilophodon or Thescalosaurus, taxa that nest with Convolosaurus in Andrzejewski, Winkler and Jacobs 2019. Soon they will be added. Then we’ll revisit this.
Convolosaurus marri (Andrzejewski, Winkler and Jacobs 2019; SMU 72834; 2.5m in length) informally nicknamed the “Proctor Lake hypsilophodont”, this specimen is known from a flock of subadults.
Andrzejewski KA, Winkler DA and Jacobs LL 2019. A new basal ornithopod (Dinosauria: Ornithischia) from the Early Cretaceous of Texas. PLoS ONE. 14 (3): e0207935. doi:10.1371/journal.pone.0207935.