SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06eeed52dc0230c8696a43ef2be205ec3a9bcc421a30a5f31ff6ebc515828a31' 
  AND token = 'WzB9LTdarc6ic51v8TgvstkrAwHLK2n1nYDQ8Ev+19w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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