The first true millipede\u20141306 legs long

Paul E Marek,Juanita Rodriguez,Mark S Harvey,William A Shear,Jackson C Means,Dennis G Black,Bruno A Buzatto

doi:10.1038/s41598-021-02447-0

Abstract

The name “millipede” translates to a thousand feet (from mille “thousand” and pes “foot”). However, no millipede has ever been described with more than 750 legs. We discovered a new record-setting species of millipede with 1,306 legs, Eumillipes persephone, from Western Australia. This diminutive animal (0.95 mm wide, 95.7 mm long) has 330 segments, a cone-shaped head with enormous antennae, and a beak for feeding. A distant relative of the previous record holder, Illacme plenipes from California, it belongs to a different order, the Polyzoniida. Discovered 60 m below ground in a drill hole created for mineral exploration, E. persephone possesses troglomorphic features; it lacks eyes and pigmentation, and it has a greatly elongated body—features that stand in stark contrast to its closest surface-dwelling relatives in Australia and all other members of its order. Using phylogenomics, we found that super-elongation (> 180 segments) evolved repeatedly in the millipede class Diplopoda. The striking morphological similarity between E. persephone and I. plenipes is a result of convergent evolution, probably for locomotion in similar soil habitats. Discovered in the resource-rich Goldfields-Esperance region and threatened by encroaching surface mining, documentation of this species and conservation of its habitat are of critical importance.

Highlights

The name “millipede” translates to a thousand feet
We report the discovery of E. persephone, the first super-elongated millipede known from Australia, and the new world record holder of the animal with greatest number of legs
In August 2020, in the Goldfields region of Western Australia, we discovered a pale, thread-like millipede with 1,306 legs at a depth of 60 m in a drill hole created for mineral exploration (Fig. 1)

Summary

Introduction

The name “millipede” translates to a thousand feet (from mille “thousand” and pes “foot”). Distantly related millipedes, such as Illacme species and other members of the family Siphonorhinidae (order Siphonophorida), have been recorded from as deep as 11.5 m below the soil surface[13,14] These species possess a suite of adaptations, such as a thin elongated body with up to 750 legs, no eyes, massive antennae, and lack of pigmentation. We report the discovery of E. persephone, the first super-elongated millipede known from Australia, and the new world record holder of the animal with greatest number of legs. It belongs to the family Siphonotidae (order Polyzoniida), yet appears similar to super-elongated millipedes in the order Siphonophorida. Eumillipes persephone lives deep underground, and it was only discovered by surveying geological drill holes originally created for mineral exploration that provided access to a cryptic and previously unexplored underground habitat

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Conclusion