SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '454ec5624b632de3bcdcc2d38d8d04899107f096ed84e6e35be0be6989a15dfb' 
  AND token = '9we8nbxpIz+vXN9KroqpOOaDpUEYJ4JM0HVBIoX/WdQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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