SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6df24f54c9dea43e78203799fe58d62cb82647ff9b6e3561282e238479cb7a36' 
  AND token = '/iFQnOkRCLQRCZ43mLTuYilGtVfhQGUj4YQVsSWyxvo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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