Pholcus phalangioies, the daddy-long-legs spider or cellar spider (also known as skull spider due to its cephalothorax looking like a human skull), is a spider of the family Pholcidae. Females have a body length of about 9 mm; males are slightly smaller. Its legs are about 5 or 6 times the length of its body. Its habit of living on the ceilings of rooms, caves or cellars gives rise to one of its common names. In Australian homes, they are considered beneficial because they will kill and eat the venomous Redback spider..