SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa68050ff2e027ea4c768730c6a93704b471a994f2f6512d7c34804239950b3f' 
  AND token = 'p0jqJ/NtmEA3TZsLT8LIZJ4dT9LVAptvpClKijjUGuw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}