SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e738d354ff31f35aec6e01a75c0818519382f20ea12bdbd5e528bbec98d699ce' 
  AND token = 'Ome6BLaVwpS64mvWhEKQvXRz7c1FOjfl41FqpvqkJE4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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