Species of Humbertium are characterized by the presence of a well developed penis papilla in the copulatory apparatus, similar to the one in Bipalium, but with the ovovitelloducts entering the female atrium anteriorly and not posteriorly as in Bipalium.
Etymology
The genus Humbertium is named after the Swiss naturalist Aloïs Humbert who described several species from Sri Lanka that are now classified in the genus.
Species
The genus Humbertium contains the following species:
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