SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '136864b5f1fd13248a4cf61558b27eb0cf18b3de6f40338af5e9e19f841cea96' 
  AND token = '2QLRJ1AIZSlpod+5sSTW67Fx8AErzzW+SEh5S5XkK5w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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