SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd88c308c45a660fc75fdadbcf1a00935dc7ff9a8425f4c44f25fd9e87b170711' 
  AND token = 'SFf8wjJ8Y1NrWhx+VHCgULoynnOolQYlGKAPmVZgSN4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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