SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a5b635b3ca10300cc2d0a09db4f7155f50e66245785d6684f1412f4f96ca6a20' 
  AND token = 'CQ9gLEVHok6VaDA0o7QKQtdwEyvElbf5VPWxE8szGMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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