"It looks like there's a whole royal necropolis of this lost dynasty," said Wegner, an associate curator at Penn's Museum of Archaeology and Anthropology.
Archaeologists had suspected the existence of the unknown pharaohs from an ancient list of rulers called the Turin King List, portions of which are torn and decayed. By analyzing fragmented parts of the list, a Danish researcher named Kim Ryholt proposed years ago that 16 unknown kings belonged to the Abydos dynasty.
The name of Senebkay matches one of the partial names on the list, said Wegner, who identified the tomb's occupant with the help of graduate student Kevin Cahail. Some other names on the list are obliterated.
"They basically were forgotten to history," Wegner said. "In the later king lists, they don't appear. They just kind of vanish."
The tomb, dated to 1650 B.C., appears to have been raided by tomb robbers in ancient times, Wegner said. Even the king's bodily remains were ripped apart.
Preliminary work on the skeleton, conducted by Penn graduate students Paul Verhelst and Matthew Olson, suggests that Senebkay stood about 5 feet, 10 inches tall and died in his mid- to late 40s.
The tomb contained remains of a funerary mask, a coffin, and a cedar chest that would have been used to house the king's internal organs, customarily removed before burial.
The chest apparently had been reused from the nearby tomb of an earlier king who already was known to history. The discovery of that tomb, belonging to a king named Sobekhotep, was announced by the Penn-Egypt team this week.
The rash of discoveries began last year, when Wegner and colleagues found a 60-ton stone sarcophagus chamber that appeared to have been moved from its original site. They identified its original owner as Sobekhotep, but are still identifying the king for whom it was reused.
The new discovery of the tomb of Senebkay occurred in the process of excavating ruins near the 60-ton chamber. The tombs of other apparent members of the dynasty are thought to lie nearby.
Senebkay's tomb is painted with images of the goddesses Nut, Nephthys, Selket, and Isis. His reign occurred during what is known as the Second Intermediate Period, a time when multiple dynasties were competing for supremacy, Wegner said.