| Species name | Agaricus arvensis |
| Common name | Horse mushroom |
| Cap | 7-15cm across, ovoid > convex > umbonate, white and smooth (slightly scaly), bruises yellow |
| Gills | White > grey/pink > brown/black, crowded, free |
| Stipe | 8-13cm, bulbous towards base, pendulous ring with cog-wheel pattern beneath |
| Growth form | Small groups, rarely fairy ring. |
| Spore print | Brown |
Spore features | Ellipsoidal, smooth |
| Habitat | Lawns, glades and verges |
Season | Autumn |
| Distribution | Widespread, common |
| i Identifying feature | Large size of cap and patterning of ring. |
| Similar species | Agaricus xanthodermus is similar but the cap tends to crack into fine scales with age. A. xanthodermus also differs in gill colour and lacks pattern under the ring. |




