SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '944a9d804dcddd0e5a0fa81cd33a192066c8a7808f8eed85ae8ef6c1e364e57b' 
  AND token = 'YqAEHtIsyODXfORMZ6xgpYzQl1MhU+qMCXuHiJl7zXk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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