SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cc7b28981194b3f48644eb23a34ab7f383f607963b2a3c946493793f75af2ac5' 
  AND token = 'ilqjYVArxH1ZXH1/WJiz1pKS+WqQx6FN5F4L3BnwUMo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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