The IGS Ka'Thelan Krotus was an Andorian Imperial Guard destroyer/warship in service during the Earth-Romulan War. The vessel was named for Krotus. (ENT - The Romulan War novel: Beneath the Raptor's Wing)
History
On November 17, 2155, the Ka'Thelan Krotus was defending Threllvia IV when the Romulans attacked. Three Romulan bird-of-prey targeted the Krotus, and the ship was seized by their telecapture system. The Krotus sent out a distress call, which was answered by the United Earth starship Enterprise (NX-01). When Enterprise arrived, the Andorians had already destroyed their ship by disrupting antimatter containment to prevent the Romulans from hijacking the warship. Enterprise recovered escape pods with a total of fourteen survivors.
A day later, Hravishran th'Zoarhi learned of the loss of the ship, whose crew complement included three former colleagues from the IGS Kumari. Together with the loss of the Tellarite starship Miracht, the loss of the Ka'Thelan Krotus led to the realization that Andorian and Tellarite technology was twice as vulnerable to the Romulan telecapture system as Human technology. That convinced the Andorian Empire and the United Planets of Tellar to drop out of the war. (ENT - The Romulan War novel: Beneath the Raptor's Wing)