SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '683e25a2d92bd1087a66aa872bf65e696d780df586db61f65f89436c0998f56f' 
  AND token = 'TaYfGsZaJ+WbB4t91qlNORSAsQ4iTn8i37/oEJzgpK8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00212

JSON explain

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