Pictured as: the Miss Mary Jean (D and S Marine) Photo by: Captain Peter

Built in 1975, by Main Iron Works Incorporated of Houma, Louisiana (hull #302) as the Cela Cenac for the Cenac Towing Company Incorporated of Houma, Louisiana.

In 1984, the tug was acquired by the Alamo Barge Lines Incorporated of Houston, Texas. Where she was renamed as the Alamo Discovery.

In 1985, she was acquired by Hollywood Marine Incorporated of Houston, Texas. Where the tug retained her name.

In 1987, Hollywood Marine Incorporated renamed the tug as the Discovery.

In 1999, the tug was acquired by the Kirby Corporation of Channelview, Texas. Where she retained her name.

In 2012, she was acquired by D and S Marine Services Incorporated of Houma, Louisiana. Where the tug was renamed as the Miss Mary Jean.

Powered by two, Caterpillar D398 diesel engines. With Caterpillar reduction gears, at a ratio of 4:1. Turning two, stainless steel, fixed pitch propellers, with kort nozzles. She is a twin screw towboat, rated at 1,700 horsepower.