SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '71d49809cfb95de6f49da464592f9e30bfd750ef647a72b291b9df0a43c7cdc0' 
  AND token = 'vChgFJkcHm/afBvEBjV3Xp143q6jIXaS5AYnK8jkSTU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}