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Abstract Closely related sexual and parthenogenetic species often show distinct distribution patterns, known as geographical parthenogenesis. Similar patterns, characterized by the existence of separate sexual and parthenogenetic populations across their natural range, can also be found in facultative parthenogens – species in which every female is capable of both sexual and parthenogenetic reproduction. The underlying mechanisms driving this phenomenon in nature remain unclear. Features of the habitat, such as differences in host‐plant phenotypes or niche breadth, could favour sexual or asexual reproductive modes and thus help to explain geographical parthenogenesis in natural insect populations. Megacrania batesii is a facultatively parthenogenetic stick insect that displays geographical parthenogenesis in the wild. We aimed to explore whether sexual and parthenogenetic populations of M. batesii displayed niche differentiation or variations in niche breadth that could explain the separation of the two population types. To do this, we sampled host plants from across the range of M. batesii and quantified phenotypic traits that might affect palatability or accessibility for M. batesii, including leaf thickness, toughness, spike size and density, plant height, and chemical composition. We also quantified host‐plant density, which could affect M. batesii dispersal. We found little evidence of phenotypic differences between host plants supporting sexual versus asexual M. batesii populations, and no difference in host‐plant density or niche breadth between the two population types. Our results suggest that habitat parameters do not play a substantial role in shaping patterns of geographical parthenogenesis in wild populations of M. batesii. Instead, population sex ratio variation could result from interactions between the sexes or dispersal dynamics.

Determining habitat characteristics and quality is important for conservation planning for threatened species of butterflies. We determined the vegetation in two Apollo butterfly habitat types and recorded the species richness and abundance of vascular plants in 12 randomly chosen plots within our study site in the “Baruun Burkh” Mountains of the Khentii Mountain Range. We also recorded the movements of adult Apollo butterflies (Parnassius apollo and P. nomion) using mark-recapture methods. Apollo butterfly habitats were heterogeneous within alpine shrub communities and meadows. Recapture results showed significant differences between mean total distances moved by P. apollo (200.31 ±38.19 m; median = 125 m) and P. nomion (218.17 ±77.35 m; median = 131 m). The number of recaptures influenced mean total distance moved, with significantly longer total movements for animals recaptured more times. The single largest movement between subsequent recaptures was 484 m for P. nomion and 543 m for P. apollo, whereas the largest total distance traveled (between all recaptures) was 728 m for P. nomion and 1,024 m for P. apollo. More research is required to conserve effectively these threatened butterflies.