SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c31c30caf1481be8fc7191ed828331eb6541f8e4c632b6df8dba54754de820cf' 
  AND token = 'nsVTH/mFpOmtwqsW+XmeoOuNsfyePeD3GfpfIqfy6p4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}