Treptichnus pedum (Seilacher, 1955)

Diagnosis.—Treptichnus burrow system consisting of subhorizontal, straight to curved primary burrow with multiple successive burrow segments branching off in regular intervals (Fillion & Pickerill, 1990; Jensen, 1997).

Remarks.—Treptichnus is interpreted as a fodinichnion made by vermiform animals (Buatois et al., 1998). Recent neoichnologic work has convincingly argued for a priapulid origin for Treptichnus pedum (Vannier et al., 2010). Originally described as Phycodes pedum (Seilacher, 1955), Jensen (1997) referred this ichnospecies to Treptichnus whereas Geyer and Uchman (1995) placed it in Trichophycus. The type specimen (Seilacher, 1955, p. 387, fig. 4a) shows branching at the end of the burrow system resulting in a sickle-shaped appearance. Jensen (1997) included more irregular branching patterns with curved to highly winded courses and alternating or single sided segments. The proposal by Jensen (1997) became generally accepted (e.g., Seilacher et al., 2005; Seilacher, 2007; Vannier et al., 2010). Although the scarcity and incomplete nature of the Hanneh specimens prevent from a definite assignment, the overall morphology corresponds with descriptions by Jensen (1997).