Obbes' Catfish (Porochilus obbesi)

Conservation status

Northern Territory, Territory Parks and Wildlife Conservation Act 1976: Near threatened.

Breeding season

A species-specific annual cycle is not provided in the supplied documents. The table therefore marks documented breeding, young and movement periods as unknown, and treats suitable aquatic habitat as requiring protection throughout the year.

Months are January to December. A value of 0 means no documented occurrence in the supplied sources, 1 means a precautionary or possible period, and 2 means a documented peak period.

• Highest clearing risk: Apply aquatic habitat and fish salvage controls in every month because breeding timing is unknown and direct mortality or habitat damage can occur whenever slow-flowing habitat is disturbed. No peak risk months are documented.

Identification

Obbes' Catfish is a small, tapering catfish that may be difficult to detect in vegetated backwaters. Identification should be based on its fin structure, body shape and colour pattern, supported by an experienced aquatic fauna specialist where required.

The body is tapering and grey to brown. Some individuals have one or two pale stripes along the side. The species has a short-based first dorsal fin and a long-based anal fin that is continuous with the caudal and second dorsal fins.

Length: Up to 12 cm, commonly up to 8 cm.

Dorsal fin: Short-based first dorsal fin, preceded by a sharp spine.

Anal fin: Long-based anal fin continuous with the caudal and second dorsal fins.

Identification: Features for field identification

The first dorsal and pectoral fins are each preceded by a sharp spine. The combination of a tapering body, catfish form, continuous anal, caudal and second dorsal fin margin, and grey to brown colouration is more useful than colour alone.

• Handle captured fish carefully because the dorsal and pectoral spines are sharp.
• Use photographs and voucher-quality records where collection is permitted, particularly in areas where the species is uncommon or records are uncertain.

Identification: Similar species and field signs

The supplied references do not provide a diagnostic comparison with other Porochilus or eeltail catfish species. Do not rely on a general 'catfish' identification where the species may affect project approvals or aquatic habitat controls.

No species-specific tracks, scats, calls, nests, sloughs or eyeshine are expected. The relevant field evidence is a live fish, a retained specimen where authorised, or a verifiable photograph and location record.

Distribution: Australian range

In Australia, Obbes' Catfish is known from the northern Northern Territory and northern Queensland. Records are scattered and the species has a disjunct distribution, with additional records from southern Papua New Guinea.

The Australian Faunal Directory records the species in the Northern Territory and Queensland. The stated range extends from Pine Creek to Yam Creek in the Northern Territory, and from north-east of Bamaga to the McIvor River on Cape York Peninsula, Queensland.

Australian Museum records include Yam Creek and Fish Creek in the Northern Territory, and the Wenlock and Jardine Rivers near the tip of Cape York. The species has also been collected from other areas in the northern Northern Territory.

States: Northern Territory and Queensland.

IBRA bioregions: Arnhem Plateau, Cape York Peninsula and Pine Creek.

Known Australian localities: Yam Creek, Fish Creek, Wenlock River and Jardine River, with additional northern Northern Territory records.

Distribution: Population information

The supplied references do not provide a population estimate, density, generation length or quantified population trend. Many authors describe the species as uncommon, but its cryptic nature means that further intensive sampling may extend the known distribution.

A Northern Territory infrastructure assessment noted uncertainty about the Yam Creek drainage assignment. It reported that the species was recorded from Yam Creek but that the record may not represent the Daly catchment.

Population size: Not reported in the supplied documents.

Population trend: Not reported in the supplied documents.

Known strongholds or subpopulations: No formally identified strongholds or subpopulations are reported.

Distribution: Outside Australia

The species also occurs in tropical southern Papua New Guinea. The Australian Faunal Directory includes type specimens from the Lorentz River at Sabang, New Guinea.

Habitat: Aquatic habitat

Obbes' Catfish uses low-velocity aquatic habitats with soft bottoms and aquatic vegetation. These habitats may occur as isolated backwaters, lagoons or shallow lakes as well as along slow-flowing streams.

The species occurs in slow-flowing freshwater streams and backwaters. Northern Territory project information identifies a preference for slow-flowing streams, lagoons and shallow lakes with considerable macrophyte growth.

The Australian Faunal Directory describes the species as benthic and associated with brackish water, freshwater and soft-bottom habitats.

Flow: Slow-flowing streams and backwaters.

Water types: Freshwater and brackish water.

Substrate: Soft bottom.

Vegetation: Considerable macrophyte growth is preferred.

• Map and avoid slow-flowing pools, backwaters, lagoons and shallow vegetated lakes within or downstream of a work area.
• Treat apparently isolated wet depressions connected to streams as potential habitat where suitable water and macrophyte growth remain.
• Maintain aquatic habitat connectivity and avoid unnecessary changes to flow, water depth or sediment conditions.

Habitat: Site setting

The supplied documents do not give elevation limits, water-temperature limits, salinity ranges, named vegetation communities or specific riparian plant associations. Habitat assessment should therefore focus on aquatic structure and flow rather than on a single terrestrial vegetation type.

• Record waterbody type, flow, depth, substrate, macrophyte cover, connection to downstream habitat and evidence of seasonal drying during pre-clearance surveys.
• Include nearby brackish reaches where the waterbody has soft substrate and low flow, particularly in northern coastal catchments.

Foraging habitat: Feeding habitat

The supplied documents do not identify the diet, prey taxa or feeding distance of Obbes' Catfish. Its benthic habit indicates that feeding habitat is associated with soft-bottom aquatic areas, but the species-specific diet should not be assumed without further evidence.

The species is described as benthic and associated with soft-bottom habitats. It is also recorded from slow-flowing streams, backwaters, lagoons and shallow lakes with macrophyte growth.

No supplied reference specifies whether the species feeds mainly on aquatic insects, crustaceans, molluscs, fish, algae or plant material.

Feeding mode: Benthic association is documented; detailed feeding behaviour is not provided.

Known prey: Not reported in the supplied documents.

Foraging range: Not reported in the supplied documents.

• Retain soft-bottom pools, submerged macrophytes, shallow backwaters and low-velocity margins where they occur within the work footprint.
• Prevent excessive sediment mobilisation, oil or chemical contamination and unnecessary removal of aquatic vegetation in occupied or potentially occupied habitat.
• Do not infer a foraging range or home range from the available records.

Breeding habitat: Breeding habitat

The supplied documents do not describe the breeding season, spawning behaviour, eggs, larvae, maturity or lifespan of Obbes' Catfish. Protection should focus on retaining suitable low-flow, vegetated aquatic habitat until species-specific breeding information is available.

The species' documented habitat includes slow-flowing streams, lagoons, shallow lakes and backwaters with considerable macrophyte growth. These features should be treated as potential breeding habitat because the supplied references do not identify a narrower breeding microhabitat.

Avoid draining, isolating, infilling or rapidly changing water levels in vegetated low-flow habitats during works.

• Survey suitable aquatic habitat before construction and before any proposed dewatering or diversion.
• Retain aquatic vegetation and soft-bottom areas unless removal is authorised under the project approval and aquatic fauna management plan.
• Use fauna salvage and translocation procedures approved for the project if fish may be trapped by isolation or dewatering.

Breeding habitat: Breeding information

No species-specific breeding data are provided in the supplied documents. The figures below should be recorded as unknown rather than inferred from other catfish species.

Breeding season: Not reported.

Clutch or litter size: Not reported.

Gestation or incubation: Not reported.

Age at maturity: Not reported.

Lifespan: Not reported.

Sheltering habitat: Likely aquatic cover

Obbes' Catfish is associated with aquatic cover rather than a documented terrestrial refuge. The supplied references do not describe nests, burrows, hollows or refuge dimensions.

The best-supported sheltering features are slow water, backwaters, lagoons and shallow lakes with considerable macrophyte growth. Soft bottoms are also part of the species' recorded habitat description.

No specific shelter structure, depth, cover density or refuge size is reported.

Documented cover: Considerable macrophyte growth in slow-flowing and lagoon habitats.

Refuge size: Not reported.

Nests or burrows: Not reported.

• Retain submerged and emergent macrophytes, low-flow margins and connected backwaters where they occur.
• Avoid prolonged turbidity, sediment deposition and mechanical disturbance of soft-bottom areas.
• Inspect isolated pools and vegetated backwaters before dewatering because fish may remain concealed and be missed by visual searches.

Threats: Clearing and construction

The main project risks are loss or isolation of slow-flowing aquatic habitat, changes to flow and water levels, sediment disturbance and direct mortality during dewatering or channel works. The species' Near Threatened status in the Northern Territory and cryptic nature warrant conservative aquatic fauna controls.

Clearing can remove or shade riparian and aquatic habitat associated with slow-flowing streams, backwaters, lagoons and shallow lakes. In-water works, trenching, crossings and dewatering can directly injure or strand fish and can disturb soft-bottom habitat and macrophytes.

The supplied infrastructure assessment states that construction should minimise impacts on aquatic environments and identifies flow obstruction, water extraction and movement of aquatic life between catchments as regulated or project risks.

• Keep machinery, spoil, fuels and concrete out of aquatic habitat and establish exclusion zones around retained waterbodies.
• Stage crossings and dewatering so fish are not trapped in isolated pools.
• Use qualified aquatic fauna personnel for fish salvage where water is to be pumped, drained or diverted.
• Prevent transfer of water, sediment, plants or aquatic animals between catchments unless authorised.

Threats: Hydrology and water quality

Obstruction or diversion of flow can alter the low-flow habitats used by the species. Water extraction, altered water levels, sediment inputs and pollution may reduce habitat quality or cause direct mortality.

The species is associated with soft bottoms and macrophyte growth, so excessive sediment deposition or removal of aquatic vegetation may reduce suitable habitat.

• Maintain downstream flows and avoid abrupt changes in depth or velocity during construction.
• Use sediment and erosion controls suited to aquatic works, and inspect controls after rainfall.
• Do not discharge turbid, contaminated or chemically altered water into occupied or potentially occupied habitat.
• Use water from the same catchment where permitted, and manage release points to avoid translocation between catchments.

Threats: Fragmentation, fire and predators

The supplied documents do not identify a species-specific effect of roads, fire, introduced predators or disease. Roads and crossings may still fragment or alter aquatic habitat through culverts, barriers, sediment delivery and changes in flow.

Apply standard aquatic fauna controls where these pressures occur, but record the causal pathway rather than attributing an unverified species-specific impact.

• Design crossings to retain aquatic passage and low-flow connectivity where required by the project approval.
• Keep cleared material, ash and sediment out of streams and backwaters after fire or vegetation removal.
• Report fish injuries, mortalities, unusual disease signs and non-native aquatic species encountered during works.

Threats: Regulatory context

Obbes' Catfish is not listed under the EPBC Act in the supplied information, but it is listed as Near Threatened in the Northern Territory. Threatened wildlife have protected wildlife status under the Territory Parks and Wildlife Conservation Act 2000 when they fall within the Act's threatened categories, so project officers should confirm the current legal status and permit requirements before handling or interfering with fish.

EPBC Act: Not listed in the supplied information.

Northern Territory: Near Threatened.

• Check current Northern Territory and Queensland legislation, permits and project approval conditions before capture, handling, relocation or habitat disturbance.
• Document all records with coordinates, waterbody name, date, method, photographs and fate of captured fish.

Survey methodology: 1. Visual and spotlight searches

Obbes' Catfish is a small, cryptic catfish of slow flowing freshwater streams, backwaters, lagoons and shallow lakes with substantial macrophyte growth. Survey design should focus on quiet, vegetated waterbodies and use more than one detection method because the available records do not provide a species-specific survey guideline.

Inspect slow-flowing freshwater streams, backwaters, lagoons and shallow lakes, with particular attention to dense aquatic vegetation and sheltered margins.

Search from the bank and, where safe and authorised, by wading or boat in shallow water. The species has been photographed at 0.5 m depth in a swampy backwater area.

Use spotlighting after dark as a general fish survey method for cryptic species, recording the start and finish time, weather, water level, visibility, search route and area covered.

The source material does not specify a required number of nights, hours, transect length or minimum search area, so the project ecologist should set effort that covers all suitable habitat and repeat searches where detection conditions are poor.

Maximum length: 12 cm

Commonly observed length: Up to 8 cm

Documented observation depth: 0.5 m

• Search slowly along vegetated margins, backwaters and shallow pools rather than only in the main current.
• Record any catfish observed, including photographs, exact coordinates, waterbody name, depth, habitat description and an estimate of abundance.
• Do not enter water where crocodiles, unstable banks, strong flow or contaminated water create an unacceptable risk.

Survey methodology: 2. Capture-based fish surveys

Use appropriately authorised fish sampling methods suited to shallow, slow-flowing and vegetated habitat, such as small nets or traps, where permitted by the relevant Northern Territory or Queensland authority.

Place sampling gear in sheltered margins, backwaters and among macrophytes, while avoiding excessive disturbance to aquatic vegetation and soft sediments.

The supplied documents do not specify trap type, mesh size, soak time, trap nights or replication for Obbes' Catfish. The ecologist must set these details in the approved survey plan and follow animal ethics, fisheries and state permit conditions.

Identify captured fish promptly, minimise handling, keep them in water wherever practicable, and release them at the point of capture unless a voucher or other retention is authorised.

• Use a consistent effort measure, such as gear type, number of sets, soak time, number of sites and area sampled, so results can be compared between sites.
• Survey both apparently suitable habitat and representative nearby habitat where access allows, because the species has a disjunct distribution and may be recorded more widely with intensive sampling.
• Clean and disinfect equipment between waterbodies to reduce the risk of transferring aquatic organisms.

Survey methodology: 3. Habitat and eDNA checks

Map all slow-flowing channels, backwaters, lagoons, shallow lakes, swampy areas and macrophyte beds within the disturbance footprint and nearby retained habitat.

Where capture or visual detection is unlikely to provide a reliable result, consider an environmental DNA survey designed by a suitably qualified aquatic ecologist. The supplied documents do not provide a validated eDNA method for this species.

Collect water samples and interpret any eDNA result with suitable controls and confirmatory fish survey methods, because the available sources describe the species as cryptic and uncommon.

• Record water permanence, flow, depth, aquatic vegetation, substrate and connectivity between the site and downstream or adjacent wetlands.
• Treat suitable habitat as potentially occupied until the project ecologist has assessed the survey results and habitat condition.

Survey methodology: Minimum effort and reporting

There is no species-specific survey guideline or minimum effort schedule in the supplied documents. The project ecologist must document the rationale for the selected methods, timing, effort and coverage.

Repeat or extend surveys when water is absent, turbid, inaccessible, heavily disturbed or otherwise unsuitable for detection.

Submit confirmed records, including negative survey results where required, to the relevant Northern Territory or Queensland wildlife or biodiversity database and provide voucher-quality photographs or specimens through the appropriate museum process.

Report the surveyors, qualifications, permits, dates, weather, water conditions, equipment, effort, locations, results, identification method and fate of captured animals.

• Check the current state database and approval conditions before fieldwork, because the supplied sources include older records and note that distribution maps may not show the entire range.
• Notify the relevant regulator if the survey identifies a new location, a concentration of animals or a potential project impact that was not assessed.

Before habitat disturbance: Avoid and minimise

Plan the work around the species' aquatic habitat rather than relying only on a fauna search immediately before clearing. The main risk is disturbance or loss of slow-flowing, shallow, vegetated freshwater habitat and connected backwaters.

Retain slow-flowing streams, backwaters, lagoons, shallow lakes, swampy margins and dense macrophyte beds wherever practicable.

Keep aquatic habitat connected to retained upstream, downstream and adjacent wetland habitat, and avoid barriers that alter flow or isolate pools.

Keep machinery, spoil, fuels, concrete washout and sediment out of waterbodies and vegetated wetland margins.

Do not drain, infill, deepen, straighten or unnecessarily disturb shallow pools and backwaters used by the species.

• Set project-specific no-go areas and waterway buffers in the approved environmental controls plan.
• Use existing access tracks and previously disturbed areas for crossings, laydown areas and stockpiles where practicable.
• Design crossings and temporary works to maintain natural flow and avoid transferring water between catchments.

Before habitat disturbance: Approvals and project planning

The supplied listing information states that Obbes' Catfish is not listed under the EPBC Act and is listed as Near Threatened in the Northern Territory.

Confirm the current legal status before works because state listings, permit requirements and project conditions can change.

Obtain any required Northern Territory or Queensland wildlife, fisheries, waterway, animal ethics and scientific collection approvals before survey, capture, handling or relocation.

Seek an EPBC Act referral assessment if another nationally listed matter or a nationally significant impact is present, even though this species itself is not listed nationally.

EPBC Act status: Not listed, based on the supplied listing information

Northern Territory status: Near Threatened

• Ask the relevant state agency whether a permit is needed to take, interfere with, possess, transport or release the species.
• Include aquatic fauna risks and controls in the fauna management plan, erosion and sediment control plan, water management plan and construction environmental management plan.
• Stage clearing so that retained aquatic habitat remains available and connected while construction proceeds.

Before habitat disturbance: Pre-clearance preparation

Complete a pre-clearance aquatic habitat inspection and confirm whether any suitable waterbody will be drained, crossed, dewatered, shaded, sediment-affected or otherwise disturbed.

Mark no-go aquatic habitat, macrophyte beds, backwaters, wetland margins, access limits and approved machinery routes before work starts.

Use exclusion fencing or visible aquatic habitat markers where they can prevent machinery and personnel entering retained habitat.

If dewatering is unavoidable, prepare a regulator-approved fish rescue and relocation plan before pumps are installed.

• Brief all workers on the species' appearance, its small size, its slow-flowing and vegetated habitat, exclusion areas, stop-work triggers and reporting chain.
• Ensure a suitably qualified aquatic ecologist and authorised fauna handler are available before any capture, dewatering or relocation activity.
• Check that sediment controls are installed and functional before earthworks begin.

During habitat disturbance: Daily work controls

Keep aquatic habitat controls active throughout construction, not only during initial clearing. A fauna spotter catcher must work as part of the construction team and must have authority to stop work where an animal or occupied habitat is at risk.

Inspect exclusion fencing, no-go markers, sediment controls, pumps, water quality controls and access routes before work starts each day.

Keep machinery, refuelling, spoil, waste and washdown activities outside retained aquatic habitat and its approved buffer.

Prevent turbid water, concrete, hydrocarbons and other contaminants from entering slow-flowing water, backwaters, lagoons or shallow lakes.

Maintain natural flow and avoid pumping water from one catchment to another, because the supplied report identifies aquatic organism translocation as an offence under the Fisheries Act 2004.

• Stop work and notify the site environmental representative if a control has failed or water is entering retained habitat.
• Use a spotter catcher or aquatic ecologist to check any work area before dewatering, waterway crossings or removal of aquatic vegetation.
• Record daily inspections, incidents, corrective actions and any changes to the approved work method.

During habitat disturbance: Fauna spotter catcher response

The spotter catcher must remain outside the water unless the task is safe, authorised and necessary, and must use an aquatic ecologist or authorised fish handler for capture and relocation.

If an Obbes' Catfish is found, stop the activity that could harm it, keep machinery and people clear, and identify the animal before deciding on a response.

Do not handle the fish unnecessarily, and do not retain, transport or relocate it unless the person and method are authorised under the relevant permit and management plan.

Where approved, release the fish into nearby retained habitat with similar slow flow, shallow water, macrophyte cover and water quality, as close as practicable to the capture location.

• Do not release the fish into an unconnected waterbody or another catchment.
• If the fish is injured, contain it in clean, aerated water and contact the nominated aquatic wildlife rehabilitator, veterinarian or relevant authority immediately.
• Record the location, habitat, time, condition, photographs, handler, permit basis, action taken and release location.

During habitat disturbance: Stop-work triggers and habitat handling

Stop work in the affected area if the species is found in a footprint that has not been assessed, if dewatering exposes occupied habitat, or if sediment, pollutants or altered flow enter retained habitat.

Stop work if a fish rescue cannot be completed safely or if the approved relocation conditions cannot be met.

Treat macrophyte beds, shallow pools, swampy backwaters and soft-bottom margins as aquatic habitat features requiring ecologist direction before removal or disturbance.

Do not remove aquatic vegetation, drain pools or move soft sediment unless the action is covered by the approved method and aquatic fauna controls.

• Isolate the affected area and contact the project ecologist and environmental manager when a trigger occurs.
• Resume work only after the animal has been managed, the risk has been controlled and the decision has been documented.
• Report any mortality, injury, unapproved capture, pollution event or suspected translocation to the relevant regulator under the project approval conditions.

After habitat disturbance: Post-clearance checks

Post-work checks must confirm that aquatic habitat remains connected, usable and free of construction impacts. Any observation of Obbes' Catfish or evidence of habitat damage should be added to the project record and regulator reporting where required.

Inspect disturbed and retained waterbodies after clearing, dewatering, crossings and major rainfall for fish mortality, stranded fish, sediment deposition, blocked flow, bank collapse and loss of macrophyte cover.

Check that temporary crossings, cofferdams, pumps, silt controls and exclusion fencing have been removed or maintained as required by the approved plan.

Search affected habitat using the project ecologist's approved aquatic survey method if the work caused a substantial change to flow, depth, vegetation or water quality.

• Complete a final aquatic fauna inspection before demobilisation from each work area.
• Photograph and map any residual impact and record whether rehabilitation or additional monitoring is required.
• Maintain habitat protection controls until the area is stable and accepted by the environmental manager or regulator.

After habitat disturbance: Monitoring and reporting

Monitor retained and rehabilitated slow-flowing habitat where the project approval or fauna management plan requires it.

Use the same survey method and effort between monitoring events where practicable, and record changes in fish detections, water depth, flow, macrophytes, turbidity and bank condition.

Report confirmed records to the relevant Northern Territory or Queensland wildlife database and report incidents, mortality, injury and permit breaches to the relevant authority.

• Retain field sheets, photographs, coordinates, survey results, handling records, permits, incident reports and rehabilitation inspections in the project environmental records.
• Review monitoring results with the project ecologist and change controls if habitat condition or detections decline.

After habitat disturbance: Offsets and residual impacts

Assess residual impacts through the project's approval process after avoidance, minimisation, rehabilitation and monitoring measures have been applied.

Do not assume that an offset replaces protection of occupied or suitable habitat during construction.

If an offset or other compensatory measure is required, design it to protect or improve comparable slow-flowing freshwater, backwater, lagoon, shallow lake or macrophyte habitat and document its legal basis.

• Obtain regulator agreement before relying on any offset, conservation agreement or alternative compensatory measure.
• Track the delivery, condition and management of any approved offset for the period required by the approval.

Rehabilitation actions: Recreate aquatic habitat

Rehabilitation should recreate the shallow, slow-flowing and vegetated freshwater conditions associated with Obbes' Catfish. The supplied documents do not nominate particular planting species, rehabilitation densities, monitoring periods or success thresholds, so these must be set by the project ecologist for the local catchment and approval.

Restore natural flow paths, shallow pools, backwaters and wetland margins rather than leaving straight, deep or isolated channels.

Re-establish locally appropriate native aquatic and fringing vegetation that provides macrophyte cover and sheltered margins.

Stabilise banks and soft-bottom areas without hardening the entire margin or removing shallow habitat.

Reconnect retained and rehabilitated waterbodies where the original hydrology and approvals allow.

• Use local provenance plants where required by the project or regulator.
• Keep stockpiles, access tracks and drainage outlets away from rehabilitated aquatic habitat.
• Do not introduce fish, aquatic plants or water from another catchment.

Rehabilitation actions: Water quality, weeds and predators

Control sediment, nutrients, hydrocarbons, concrete and other pollutants during establishment and until the site is stable.

Remove declared or invasive weeds using methods that do not create harmful chemical or sediment inputs to the waterbody.

Manage erosion and weed reinvasion so that macrophyte cover can establish without smothering by sediment.

Assess predator and pest risks as part of the local wetland management plan, without introducing new species or altering habitat in ways that favour them.

• Inspect rehabilitation after rainfall and during periods of low flow.
• Repair scour, blocked flow paths, failed sediment controls and bare banks promptly.
• Use fire management appropriate to the local wetland and fringing vegetation, avoiding fire effects that remove aquatic cover or increase sediment delivery.

Rehabilitation actions: Monitoring and success measures

Set measurable site-specific targets for flow, water depth, water quality, macrophyte establishment, bank stability, connectivity and absence of construction debris.

Monitor for Obbes' Catfish using the approved project method and compare results with pre-work records where those records exist.

Investigate failed rehabilitation where suitable shallow, slow-flowing and vegetated habitat is not re-established or where fish mortality, isolation or persistent poor water quality occurs.

• Record monitoring dates, effort, weather, water conditions, habitat condition, fish detections and corrective actions.
• Continue maintenance and monitoring until the approved success measures are met and the environmental manager or regulator accepts the outcome.
• Submit significant new records and relevant rehabilitation outcomes to the appropriate state biodiversity database.

Sources

• Australian Faunal Directory, biodiversity.org.au: https://biodiversity.org.au/afd/taxa/Porochilus_obbesi
• Obbes' Catfish, Porochilus obbesi Weber, 1913, Australian Museum: https://australian.museum/learn/animals/fishes/obbes-catfish-porochilus-obbesi/
• Microsoft Word - R001 TTP Aquatic Fauna Report vFINAL.doc, Northern Territory Government: https://ntepa.nt.gov.au/__data/assets/pdf_file/0003/290739/appendixj.pdf