SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e817f0fc7b57b5f2ef5ec79b994078c39c7d3e0699653a590a5d47d2673e9742' 
  AND token = 'tilzKhV+IJ13CFvlvihYnCIz23Z+wFNrWEy1FspgQqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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