SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bac4265c9d2562815903502e1b050f729d180033180d4e4b7d219ebc5f12d8da' 
  AND token = 'DmYgLwEhs5dxDJ/n4EawPayeKlsi6QJOcvfsKMrt5zY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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