Setirostris eleryi differs from all other bats in the family by possessing unique dentition and genital morphology, a distinctive echolocation call structure, and notably smaller body size of around 5 grams (0.18 ounces).

The presence of stout bristles on the thin muzzle and face of S. eleryi distinguishes them from similar genus Ozimops, once regarded as "Mormopterus species", that previously included parts of the population.

The description, first published in 2008, emerged from a comparison of morphological features with an earlier phylogenetic analysis that had indicated cryptic species amongst this poorly-known group of bats.

The differences between these two species and remaining taxa in the 'Mormopterus planiceps group', or 'planiceps–beccarii–loriae complex', previously published as an interim arrangement, led to the erection of four new subgenera in 2014.

[3][6] The type specimen was collected at an elevation of 240 metres (790 ft) near Eringa, a cattle pastoralist lease (station) close to the northern state border of South Australia.

[5] Setirostris eleryi is a very small microchiropteran, with a light build, and was regarded as tiny when compared to species of Mormopterus, the genus of smaller bats in which they were variously placed.

[7] The muzzle and face are sparsely covered in fine hair, with the exception of a unique series of 26 to 30 conspicuous bristles on each side and a fringe of fur on the upper lip.

[2][9] The presence of outlying records for S. eleryi at Kaltukatjara (southwestern Northern Territory), Mount Isa (northwestern Queensland) and in the area south of Bourke (northwestern New South Wales) indicate that the species may have a more extensive distribution in the arid and semi-arid regions of NSW, Queensland, the Northern Territory and Western Australia than available records indicate.

[10] Records of S. eleryi are of individuals captured in mist nets or harp traps in riparian habitats on ephemeral streams, floodways, pools or dams, usually at sites supporting a large fringe of eucalypt trees.

[2][11][7][10][12][13] Capture sites are consistently associated with riparian and floodplain habitats that support a canopy of eucalypts, including Eucalyptus camaldulensis, E. coolabah, E. microtheca, E. populnea, E. polyanthemos and E.

[12][14] During radio tracking studies at the Gundabooka site the species was observed to preferentially forage along drainage lines and open channels, rarely moving into adjacent mulga vegetation dominated by Acacia aneura.

At the type locality in northern South Australia S. eleryi was captured on a floodway in Acacia cambagei low woodland with emergent Eucalyptus coolabah.

The observations are along drainage lines and open channels, flying with slow fluttering movements below the canopy at a low altitude of 3 to 4 metres (9.8 to 13.1 feet).

[12][16] Prey items are noted as flying invertebrates, captured in the air close to the ground or adjacent vegetation by the chiropteran strategy that is similar to gleaning by birds.

[20] Identified and potential threats to populations of S. eleryi are related to the direct and indirect actions of humans, including: land clearing,[20] timber harvesting, manipulation of water resources, altered fire regimes, use of pesticides, stocking with exotic ruminants, spread of feral animals and weeds,[12] and atmospheric pollution leading to global warming.

[20] The eastern Australian bioregions that comprise the core range of the species, particularly the Brigalow Belt (north and south), have been subjected to broad-scale clearing and habitat modification since European settlement.

[20] Additional key threatening processes that are considered likely to impact S. eleryi include: the alteration to natural flow regimes, competition from introduced western honey bees (Apis mellifera) for tree hollows, inappropriate fire regimes, reduction of invertebrate prey related to pesticide drift and lack of tree regeneration due to overgrazing and weeds.

[12] Climate can influence bat distribution, movements and biogeography, access to food resources, timing of reproduction, and emergence and rate of energy expenditure.

[21] The affinity of S. eleryi for riparian zones in arid and semi-arid environments renders it potentially vulnerable to the effects of water stress and extreme weather events.