Lotosaurus adentus (Zhang 1975) Ladinian, Late Middle Triassic ~240 mya, 2.5 m in length. Nesbitt (2003) considered Lotosaurus a rauisuchid close to Arizonasaurus, but it bears only a superficial resemblance. The spine sails were convergent. Weinbaum and Hungerbuhler (2007) assigned Lotosaurus to the Poposauridae (Effigia + Shuvosaurus) in 2007, which agrees with the present study. Brusatte et al. (2010) also kept Lotosaurus with the poposaurids, but also brought in Arizonasaurus, Yarasuchus and Qianosuchus, which are more distantly related.
Distinct from Silesaurus the skull of Lotosaurus was shorter, taller and had no teeth. The premaxilla was relatively larger and the maxilla relatively shorter.
The cervical series was compressed. All the neural spines were taller, the result of elongated scutes fused to underlying bone.
The scapula was massively expanded. The rest of the forelimb was robust. See Ticinosuchus for the phylogenetically closest manus, which was structurally similar, but shorter.
Distinct from Silesaurus, the pubis extended ventrally and was relatively shorte and shorter than the ischium. The hindlimbs were more robust. Digits II and III were the longest. Atypical for this clade digits 1 and 5 were robust, following the pattern seen in Qianoschus, Ticinosuchus, Scleromochlus and Gracilisuchus.