Xystocheir dissecta taibona Chamberlin, 1912. North America, USA, California, Santa Clara Co. Photo courtesy of W. P. Leonard.

Motyxia tiemanni Causey, 1960. North America, USA, California, Tulare Co., 2 mi. W Three Rivers. Photo by Darwin Tiemann.

Motyxia sequoia sequoia (Chamberlin, 1941) North America, USA, California, Tulare Co., 8.5 mi E Hammond. Photo by Darwin Tiemann.

?Wamokia sp. North America, USA, California, El Dorado Co., American River Canyon nr. Auburn. Photo courtesy of D. Ross.

Motyxia sequoia alia Causey & Tiemann, 1969, dorsal view of full bioluminescence. North America, USA, California, Tulare Co. Photo courtesy of D. Fenolio.

Xystocheir m. modestior (Chamberlin, 1941). North America, USA, California, Fresno Co., 3 mi S O'Neals. Photo by Darwin Tiemann.

Motyxia tiemanni Causey, 1960. North America, USA, California, Kern Co., Shirley Meadows. Photo by Darwin Tiemann.

Motyxia pior Chamberlin, 1941, under black light. North America, USA, California, Tulare Co., Dry Creek. Photo by Darwin Tiemann.

Motyxia sequoia alia Causey & Tiemann, 1969. North America, USA, California, Tulare Co. Photo courtesy of D. Fenolio.

Motyxia sequoia alia, lateral view of nearly full bioluminescence. North America, USA, California, Tulare Co. Photo courtesy of D. Fenolio.

Motyxia tiemanni Causey, 1960. North America, USA, California, Kern Co., Shirley Meadows. Photo by Darwin Tiemann.

Motyxia tiemanni Causey, 1960, instars emerging from molting chambers. North America, USA, California, Kern Co., Shirley Meadows. Photo by Darwin Tiemann.

Motyxia sequoia sequoia (Chamberlin, 1941), mating pair. North America, USA, California, Tulare Co., Camp Belknap. Photo by Darwin Tiemann.

?Wamokia sp. North America, USA, California, El Dorado Co., American River Canyon near Auburn. Photo courtesy of D. Ross.

Motyxia sequoia alia Causey & Tiemann, 1969, lateral view of partial bioluminescence. North America, USA, California, Tulare Co. Photo courtesy of D. Fenolio.

Motyxia s.  sequoia (Chamberlin, 1941) North America, USA, California, Tulare Co., 8.5 mi E Hammond. Photo by Darwin Tiemann.

Phengodid beetle larva, Zarhippis integripennis, capturing Motyxia tiemanni Causey, 1960. North America, USA, California, Kern Co. Photo by Darwin Tiemann.

?Wamokia sp. North America, USA, California, El Dorado Co., American River Canyon near Auburn. Photo courtesy of D. Ross.

?Wamokia sp. North America, USA, California, El Dorado Co., American River Canyon near Auburn. Photo courtesy of D. Ross.

Motyxia sequoia alia Causey & Tiemann, 1969, juvenile; the black line is the dorsal haemolymph vessel. North America, USA, California, Tulare Co. Photo courtesy of D. Fenolio.