It might be of interest that Thirioux was one of the keenest collectors during the early paleontological exploration in Mauritius (besides Theodore Sauzier and Paul Carié). Findings in the account of Thirioux include:
Pteropus sp., Anas sp., Aphanapteryx
bonasia, Dryolimnas cuvieri, Fulica newtoni, Falco punctatus,
Circus maillardi, cf. Nesoenas picturata, Alectroenas nitidissima,
Lophopsittacus mauritianus, Lophopsittacus sp., Necropsittacus
rodericanus, Nesoenas mayeri, Psittacula echo, Psittacula
bensoni, Mascarenotus sauzieri, cf. Mascarenotus murivorus,
“Courlis ou Corbigeau” (curlew), “Oiseau mouche,”37 Aves indet.
(including passerines), Cylindraspis inepta, Cylindraspis triserrata,
Asterochelys radiata, Leiolopisma mauritiana, Leiolopisma telfairii,
Gongylomorphus bojeri, Cyrtodactylus serpensinsula, Phelsuma
guentheri, Phelsuma sp., Anura sp., Naso sp., Trophidophora
carinata, and Plegma duponti.
(cited from Jolyon C. Parish: The Dodo and the Solitaire, p 363)
He collected also the holotype of the Mauritius Starling (Cryptopsar ischyrhynchus), the most complete skeleton of the red rail (Aphanapteryx bonasia) and the last two specimens of the Rodrigues day gecko (Phelsuma edwardnewtoni) shortly before the extinction of this gecko species and his own death in 1917.
Thirioux is commemorated in at least four species:
Thirioux's grey parrot or Mascarene grey parakeet (Ptittacula bensoni)
Mauritius wood-pigeon (Columba thiriouxi)
Copelatus thiriouxi, a beetle from Mauritius
Erepta thiriouxi, a mollusc from Mauritius
It may be a bit harder to exclude entirely the possibility of a samesake, though -- this region appears to be the stronghold of the name 'Thirioux', and 'Louis' and 'Étienne' were certainly quite frequent given names back then.)
