SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9a00952395762c5e96a4154c64eef3cb8e70e993a03aa4ecdf0a6f50023002f' 
  AND token = '2sUziR99NgO9XtitmhA9XeVaTdwqz0U0pNVkHA8qaps=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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