SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58b8c081a721e82b90e633d77551676862e1f4385253adf01e5a708dce99c1f8' 
  AND token = 'KgNEBKNgRUWAUDH/f0StZ4woZvWWw1XqaScngVvVwx8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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