SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '669b76ccc2d34747d25e8181ac65708fc4f37a59df8ec475b515ffa411ff225f' 
  AND token = '5ugRKeSJVEjxT1H9hGJnYfbGeVjVfg3tJHW9ZhszUe4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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