Most leaves finely toothed at least toward apex (5–8 teeth per cm when mature), the veins anastomosing and becoming indistinct near the margin, at most with weak veinlets ending in the teeth; petals ca. 5–9 (–10) mm long; plants typically spreading underground and forming colonies of low shrubs
ON calcareous gravelly soils. From MF key "Most leaves finely toothed at least toward apex (5–8 teeth per cm when mature), the veins anastomosing and becoming indistinct near the margin, at most with weak veinlets ending in the teeth; petals ca. 5–9 (–10) mm long; plants typically spreading underground and forming colonies of low shrubs."
Possibly Crataegus succulenta, but photos of the flowers are needed.