SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4484d34d986c14e2802e4d80cd5b7a5768d665b375cb7a6ea587d1f6e1fdf990' 
  AND token = 'dNaKuuJfEDYlI99CUeCOS74W/pRxlD9hPw1OdRSHc3Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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