SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '730857f6fd3484d045ff04b00109aa7f5a891d28bce345b284abfb263288912f' 
  AND token = 'he1cxGS8dWvVjk55nu9ulwCMeZnzNhBhJGDax5KkWDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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