SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6834c59d60b30597c9bf903902291b3ca34420759dc68e95cef4c703d061c60d' 
  AND token = 'xV4XuDyCnNjRWPi0IiVRGYHpHTMa0D9ncgS+oJi4N8s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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