SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60a6be0463268f68ab683bee1cb6c1522f45fd544ee6cddef5d96f62e87c7dc6' 
  AND token = 's1IJoURiQHwdEmOPQKGaZdyrJplgjnYqvYIh8rxo+gc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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