SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c2f72b5016e24c82d7e68eb9302029f4b1b9d6db73747d40c79e4ad7fae90ab3' 
  AND token = 'THxvnGKP8zvmzCccllIWvKCEnXwvJQt8howCgIkTcDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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