SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fe273a839629cfb40c64765b0c0e8fa67b86433e3b7096cbf88a3bbcdd62bd1' 
  AND token = 'sC+A2jDAWWxIXi5n4UFeoJgmkzcvgaTE/BAQFwDJvvw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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