SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5a9d340e5d3d53186ee70db1d09246c3fc45a30b44f05c69feddd6d749007d51' 
  AND token = 'TarwYwD0KgQds7PU6jEINHFNdq2QlU+h1SC+jGjvLR8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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