Ledumahadi was likely a quadruped, as determined by analysis of the circumference of itshumerus andfemur compared to those of other dinosaurs. It would have had very large, robust forelimbs, consistent with those of its relatives. Unlike those of later sauropods, these limbs were naturally flexed, as opposed to being purely columnar.[1][3]
At its time in theEarly Jurassicepoch,Ledumahadi is thought to have been thelargest land animal that had ever lived.[1] At the age of 14 years,L. mafube is estimated to have reached a maximum size of around 12 tonnes (13 short tons) in body mass, significantly larger than its relatives.L. mafube was more comparable to the later sauropodDiplodocus in body mass.[1][3] Anichnotaxon namedTetrasauropus belongs to a sauropodomorph that is estimated to have a hip height of 2 m (6.6 ft), meaning that it likely belongs toLedumahadi.[4]
Aphylogenetic analysis ofLedumahadi mafube was performed by McPhee and colleagues, which found it to belong to a recently recognisedclade ofsauropodiformes calledLessemsauridae, including the closely related South AfricanAntetonitrus andLessemsaurus fromArgentina. Another lessemsaurid described in 2018,Ingentia, could not be included in their analysis but was also recognised as belonging to Lessemsauridae. The results of McPhee and colleagues' analysis are shown in the cladogram below:[1][3]
The size of the taxon was deemed to be important in the wider picture of sauropodomorph evolution, similar to its other lessemsaurid relatives. Living only a few million years after theTriassic-Jurassic extinction event, it indicates that this event must have either had only a small effect on body size within the sauropodomorph lineage, or may have not affected it at all. Significance was also found in the magnitude of the size itself—it lacked the columnar limbs that characterized its more derived relatives, thought to be a key adaptation in body size evolution. Ornithischian dinosaurs reach their largest sizes around a similar size of 12 to 17 tonnes in weight. This may have been the upper limit for dinosaurs without adopting the characteristics found in true sauropods, which grew to be several times the weight ofLedumahadi.[1][3]
