SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b72d8243c9a6023117b6b0f24e8b2377d79930b99ce2d90f901df417bee83e26' 
  AND token = 'LwiE+7rXbP7tIq4Z53+wOveg2BSbTLbxISwa9upcbFc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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