SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6f7b6051127f76d41804e891a60c22d177e3e79758fe4c475f2198daeab2c91f' 
  AND token = 'IsbZP8FzsM3hIyKNQs6bCj2CzZGWg9dX07q+YiDl1pU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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