SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24658433479af69f302a0709f59bc95246a35fccec90e1cfa923d3dab6dae9c8' 
  AND token = 'Y8atoKGRgiX8ZGcic8bNwSvu8cfyk4wNljHLtwmWFqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}