Box Chinese lingulides

Did early lingulides live in burrows like many of their descendants? Xianshanella haikouensis from the Lower Cambrian Chengjiang fauna, South China was a subcircular animal with horny setae and a massive pedicle. Zhang Zhifei and his colleagues (2006) have shown that these earliest brachiopods did not live in burrows, but actually attached themselves to the shells of other invertebrates - an epibenthonic rather than infaunal mode of life (Fig. 12.10). Moreover the Chengjiang lingulide has a lophophore, a U-shaped digestive tract and an anteriorly-located anus; these advanced features were already present in the lingulate brachiopod lineage right from the start it seems.

Figure 12.10 Chinese lingulides: Reconstruction of the Chengjiang lingulid Xianshanella. A, anal opening; B, brachial arm; Co, cone-like organisms; Ct, cheek of trilobite; Dd, digestive tract; Dva, dorsal visceral area; Pc, pedicle cavity; St, stomach; Um?, possible umbonal muscle; Vs, setae fringing ventral valve; Vva, ventral visceral area. Scale bars, 2 mm. (From Zhang et al. 2006.)

Figure 12.10 Chinese lingulides: Reconstruction of the Chengjiang lingulid Xianshanella. A, anal opening; B, brachial arm; Co, cone-like organisms; Ct, cheek of trilobite; Dd, digestive tract; Dva, dorsal visceral area; Pc, pedicle cavity; St, stomach; Um?, possible umbonal muscle; Vs, setae fringing ventral valve; Vva, ventral visceral area. Scale bars, 2 mm. (From Zhang et al. 2006.)

Lingula sp.

Eocoelia curtisi

Pentamerus oblongus

Costistricklandia lirata alpha

Clorinda globosa

Eocoelia curtisi

Costistricklandia lirata alpha

Clorinda globosa

U Outcrop area

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