References of "Lethaia"
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See detailInferring internal anatomy from the trilobite exoskeleton: the relationship between frontal auxiliary impressions and the digestive system
Lerosey-Aubril, Rudy; Hegna, Thomas; Olive, Sébastien ULg

in Lethaia (2011), 44(2),

The digestive system of trilobites is rarely preserved. As a result, many aspects of its organization remain unknown. Fortunately, the exoskeleton sometimes preserves evidence of soft-tissue attachment ... [more ▼]

The digestive system of trilobites is rarely preserved. As a result, many aspects of its organization remain unknown. Fortunately, the exoskeleton sometimes preserves evidence of soft-tissue attachment sites that can be used to infer internal anatomy. Among them are the frontal auxiliary impressions (FAIs), probable soft-tissue insertion sites located on the fronto-median glabellar lobe of some trilobites. FAIs are herein described in the Carboniferous trilobite Phillipsia belgica Osmo´ lska 1970 – representing the only known example of such structures in the Proetida and their youngest occurrence. A taphonomic scenario is proposed to explain their variable preservation. Although particularly common in the Phacopina, FAIs or FAI-like structures are also found in several orders that differ greatly. Comparisons with modern analogues suggest that FAIs might represent attachment sites for extrinsic muscles associated with a differentiated crop within the foregut. A review of purported remains of the trilobite digestive system indicates that it usually consisted of a tube-like tract flanked by a variable number of metamerically paired diverticulae. Its anterior portion is not particularly individualized, except in a few specimens that might hint at the presence of a crop. This differentiation of a crop might have constituted a secondarily evolution of the foregut in trilobites, occurring independently in different clades. Accompanied by a strengthening of associated extrinsic muscles, this modification of the foregut might explain the presence of more conspicuous muscle insertion sites on the glabella. Study of FAIs might therefore provide new data on the anatomy of the foregut in trilobites and evidence of diverse feeding habits. [less ▲]

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See detailPredatory boreholes in Tournaisian (Lower Carboniferous) spiriferid brachiopods
Mottequin, Bernard ULg; Sevastopulo, George

in Lethaia (2009), 42

A brachiopod fauna from the uppermost part of the Tournaisian Tournai Formation (Belgium) contains an undetermined species of Crurithyris (Spiriferida, Ambocoeliidae), which displays numerous bored shells ... [more ▼]

A brachiopod fauna from the uppermost part of the Tournaisian Tournai Formation (Belgium) contains an undetermined species of Crurithyris (Spiriferida, Ambocoeliidae), which displays numerous bored shells. About 8% of the 432 specimens with conjoined valves display single, small (≤ 1 mm) boreholes, which are smooth-sided, cylindrical or weakly conical, circular to slightly elliptical in plan view, perpendicular to the shell surface and generally complete. Of the 35 bored articulated specimens, 27 were drilled on the ventral valve. Most of the boreholes are located in the posterior half of the shell, and no case of edge-drilling has been observed. The boreholes were drilled by a predator, or possibly a parasite, which selected individuals greater than 2.5 mm long. Crurithyris sp. may have represented an attractive (in terms of energy cost) and easy target for a small-sized predator because of its thin shell and ornament of minute spines. [less ▲]

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See detailSphinxiocarpon, a new name for Sphinxia Li, Hilton & Hemsley, 1997 - not Reid & Chandler, 1933
Wang, Qi; Xue, Jinzhuang; Prestianni, Cyrille ULg

in Lethaia (2007), 40(4), 393-393

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