The Cave Lion (Panthera spelaea and Panthera fossilis)

[tigerluver]

A gigantic P. fossilis

Reading through records, no one noticed Sabol's (2014) giant. The paper:
Panthera fossilis (REICHENAU, 1906) (Felidae, Carnivora) from Za Hájovnou Cave (Moravia, the Czech Republic): a fossil record from 1987 – 2007
The reason may be that this specimen is nothing more than a humerus in which about a 3/5 of it remains distally. However, the width measurements caught my eye. Unfortunately, there are no measurements in other literature that correspond to what Sabol took. Nonetheless, Sabol presented a beautiful image with a 3 cm scale bar which was almost 99% accurate allowing measurements of more common humeral dimensions.

Here is probably the largest humerus of a pantherine we will see for a long while:

*This image is copyright of its original author

For comparison, the widest P. atrox humerus had a greatest distal width of 111.3 (and a total length of 396 mm). The longest P. atrox specimen (humeral length = 409 mm) had a distal width of 107.6 mm. Using the ratios of the P. atrox femurs, this P. fossilis humerus would be 441 mm in total length. 

Then we have the midshaft width comparison. This specimen midshaft traverse width of about 45 mm exceeds that of the two largest P. atrox humeri (length = 396 mm, midshaft width = 41.4; length = 409 mm, midshaft width = 38.2 mm). Using the P. atrox midshaft widths we get a total humeral length of 455 mm for this P. fossilis specimen.

Comparing the P. fossilis fragment to a few cave lion and American lion femur it look to be about 450 mm in total length. Therefore, the massive width dimensions alongside the predicted length put this specimen in the candidacy for the largest cat on fossil record to date. 

Comparing the 43 mm tranverse width at the point of least circumference to a 32.5 mm wide, 187 kg lion bone puts this specimen at 450 kg in my estimation, probably outsizing the giant 465 mm ulna and the 192 mm MT3 (which may be proportionately longer in P. fossilis looking at Marciszak et al. 2014 data). Reply