Phylogeny and taxonomy of a new clade of Australian Heliozelidae in the genus Prophylactis Meyrick, 1897 (Lepidoptera, Adeloidea) pollinating Boronia (Rutaceae: Sapindales)

Abstract

Heliozelidae are a group of small monotrysian moths with a near world-wide distribution. While the Heliozelidae fauna of the Palaearctic and Nearctic is relatively well known, few studies have examined Heliozelidae in other regions of the world. If known, described species are leaf miners as larvae; however, the early biology of species outside of the Northern Hemisphere is poorly understood.

Here, we describe a group of heliozelid moths that are specialised pollinators of the iconic plant genus Boronia Sm. (Rutaceae) from the south of Western Australia. Females of this group are characterised by the presence of a pollen-collecting structure on the dorsal side of the abdomen that is unique among known Lepidoptera.

We propose that these moths are involved in a brood pollination mutualism with their species-specific host plant, where females lay eggs into and pollinate Boronia flowers, and larvae consume developing seeds. Molecular phylogenetic analyses using seven mitochondrial protein coding genes recovered a monophyletic group of pollinator species that belong to a larger group of Rutaceae - associated Australian Heliozelidae. The remainder of this group lack this pollen-collecting structure, providing insights into the evolution of pollination relationships.

We resurrect the genus name Prophylactis Meyrick, 1897 stat. rev. and describe 15 new species based on a combination of morphological and molecular characters and host plant information: Prophylactis albiflorallax Hilton, Young & Kallies sp. nov., P. binbin Hilton, Young & Kallies sp. nov., P. clavatallax Hilton, Young & Kallies sp. nov., P. crassifoliallax Hilton, Young & Kallies sp. nov., P. crenulatallax Hilton, Young & Kallies sp. nov., P. gracilipax Hilton, Young & Kallies sp. nov., P. heterophyllax Hilton, Young & Kallies sp. nov., P jasperae Hilton, Young, Milla & Kallies sp. nov., P. megastigmallax Hilton, Young, Halsey, Milla & Kallies sp. nov., P. molloyax Hilton, Young & Kallies sp. nov., P. octandrallax Hilton, Young, Milla & Kallies sp. nov., P. pulchellax Hilton, Young & Kallies sp. nov., P. purdieanallax Hilton, Young & Kallies sp. nov., P. strictallax Hilton, Young, Halsey & Kallies sp. nov., and P. tetrandrallax Hilton, Young, Milla & Kallies sp. nov.