SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '433f3781ac6fb16bbbd3cf3984dad10ccad3d67012a4376f419eed95f6ac6dee' 
  AND token = 'xwK6Mk3PraE9Zx75nLFLnkcibCeT/0LwHucKWRCIUBY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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