SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '024a8eb7dd660e787d1e46e8c44be44a85fe4229838884a66887ad566f98cb63' 
  AND token = 'IqTQ4ibFVDfHL1f09fCS23VNDZiT5Cqejtjq8ItxC9Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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