SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '00c38adba18f837a0fd3058e0e4e8cdc3e7ff43fff7c71d45ed2848345dccea8' 
  AND token = 'C1l15YqTvBw0+1SLAmAJbuyFnSj5DlXe6nlvxaZ7ZAA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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