Corresponding author: Michael Balke (
Academic editor: O. Moldovan
Watts CHS, Hendrich L, Balke M (2016) A new interstitial species of diving beetle from tropical northern Australia provides a scenario for the transition of epigean to stygobitic life (Coleoptera, Dytiscidae, Copelatinae). Subterranean Biology 19: 23–29. doi:
The diving beetle genus
Here, we describe a new species collected from a small pool in the bed of a slowly flowing wet-season creek near Darwin. Morphological features such as reduced eyes and vestigal wings, light pigmentation and absence of the species from other nearby water bodies suggest this is an interstitial species providing a scenario for the transition from epigean to stygobitic life. This discovery highlights the hidden diversity of an underexplored habitat.
Morphological observations were made and measurements were taken with a Leica M205 C stereomicroscope. Specimens were illuminated by a diffuse 13W fluorescent double light tube.
A DNA sequence of the 3’ fragment of the mitochondrial cytochrome oxidase 1 gene was generated by Remko Leys at the South Australian Museum in Adelaide, using the oligonucleotide primers Jerry and Pat (TCC AAT GCA CTA ATC TGC CAT ATT A / CAA CAT TTA TTT TGA TTT TTT GG).
Digital images were taken with a Nikon D3X equipped with a bellow or expansion rings and lenses: Mitutoyo 10x ELWD Planapo or Leitz Photar 25/2.8. Illumination came from three compact Nikon flashes, and the instrument was moved on an Isel linear drive (
Small seasonal creek [
European nucleotide archive (genbank) accession number for the 3’ end of the mitochondrial cytochrome c oxidase 1 gene:
The name is an adjective is the nominative singular derived from the locality name – Holmes Jungle. Latin: saltus = woodland.
The species is sister to a clade containing
A small pool in the bed of a small ephemeral creek through eucalypt woodland. A small eyed, wingless
Habitus of
Habitus of
Right lateral aspect of head of
A number of West Palearctic diving beetle species are known from wells or from the interstitial of gravel banks along rivers. These were classified as semi-subterranean or interstitial species. Morphological characters hinting at this include the reduction of eyes, depigmentation, presence of long sensory setae and the reduction of wings (e.g.
While the Australian ground water fauna is well studied and is now known to harbour a considerable diversity of diving beetle species (
We thank Eduardo (“Edu”) Orduña (El Pont de Suert, Spain) and Hans Fery (Berlin) for his help composing the name properly and Remko Leys (Adelaide) for sharing DNA sequence data.