"1020379638"^^ . . . . . . "Bactrotheca"@en . . "Bactrotheca is an extinct genus of orthothecid hyolith with a bulbous \"protoconch\"."@en . . . "55505363"^^ . "405"^^ . . . . "Bactrotheca is an extinct genus of orthothecid hyolith with a bulbous \"protoconch\"."@en . .