Notorhinus floresi sp. nov. gen. nov.: The first records of Siphonophorida in Chile and Siphonorhinidae in South America (Colobognatha)

Abstract

The millipede family Siphonorhinidae (order Siphonophorida) shows a scattered distribution in South Africa, Madagascar, India, Southeast Asia, and North America. So far, the family is unknown from South America, while species of Siphonophoridae, the second family of the order, are relatively abundant on the continent. However, not a single Siphonophorida is known from Chile. Here we describe the monotypic genus Notorhinus gen. nov. with N. floresi sp. nov. and record a second Notorhinus (undescribed) species, as first records of the order Siphonophorida in Chile and of the family Siphonorhinidae in South America. Notorhinus gen. nov. is distinct from the remaining Siphonorhinidae by the arrangement of the sensilla basiconica on the antennae and other somatic and sexual characters. However, it shows close morphological affinities to the North American genus Illacme Cook and Loomis 1928. In the Americas Siphonorhinidae were previously only known from California (USA), where they inhabit subterranean micro-habitats. The Chilean species was found under a piece of decaying wood in a small patch of fragmented native forest. Thus, the group shows a disjunct antitropical distribution in America at ca. 37° North and 38° South. They might be the relict of a once greater distribution, which persisted in these areas due to similar climatic conditions.