SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6fdf549126a664f57758f79b0057b085d9bf46469a0d85c6ab2437dc8b1554a9' 
  AND token = 'O1GZ78aZ22/VIIPMfuM6YSmllFazySM7gSH8VtU2dFA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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