SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba9bd6c17a434bfba7a6b2e7d671f9cbfd6434603b3535d6abe19a2f3fc38027' 
  AND token = 'j7KkYUXFZYks7vu0iXw0O85R+ds9whIzZh/TaSD43G0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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