SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09364c51fa87a910ad0557a050af3d2711fd4398fde8e6ff90d968f05799ab74' 
  AND token = 'NcKswBOYElE7ZlRWbFQrnyUdmo55JBgj0FzJEMOPZ/o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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