Neotrygon romeoi: A new species of Blue-spotted Maskray from Fiji.

Maskrays, Neotrygon spp., are a group of Stingrays, Dasyatidae, found in the Indian Ocean and west Pacific. They get their name from a distinctive coloured marking around the eyes, which resembles a mask, but have a number of other distinctive features, including short tails with well developed dorsal fins, small mouths with enlarged cuspid teeth, and large pectoral fins with a single row of thorns along their dorsal midline. All Maskrays were formerly thought to belong to a single widespread and somewhat variable species, Neotrygon kuhlii, but genetic studies have shown that there are in fact a range of species, with sixteen species described to date, nine of them since 2016, and thirteen of these belonging to a species-complex known as the Blue-spotted group.

In a paper published in the Journal of Fish Biology on 9 June 2025, Kerstin Glaus of the Institute of Marine Resources of The University of the South Pacific, William White and Helen O'Neill of the Australian National Fish Collection, Sarah Thurnheer of the Ecosystems and Landscape Evolution at Eidgenössische Technische Hochschule Zurich, and Sharon Appleyard, also of the Australian National Fish Collection, describe a new species of Maskray from Fiji.

Fiji has long been known to be home to a population of Blue-spotted Maskrays, which are the most widely traded Ray in local fish-markets, but which have never been the subject of a taxonomic study. Glaus et al.'s study was carried out using specimens purchased in Suva Fish Market on Viti Levu Island or obtained from local fishermen. No Rays were killed specifically for the study. A genetic analysis found that these specimens all belonged to a single species, and that this species was previously unidentified, and was a sister species to the previously described Neotrygon kuhlii from the Solomon Islands.

Glaus et al. name this new species Neotrygon romeo, in honour of the late Romeo Glaus, father of Kerstin Glaus, in recognition of his lasting inspiration, enduring support and deep respect for nature. Specimens of Neotrygon romeo have quadrangular disks, weakly convex at the front, and broader than they are long. They range from 310 to 397 mm in width and from 80.6 to 84.2 mm in length, or from 176.9 to 213.1 mm in length including the tail. A single row of thorns is present on the midline. There are two tail stings. Living specimens are beige-to-medium brown, with a slight greenish tinge. The disk has a sparse scaterring of spots, these having a white centre and a diffuse-edged dark-grey to blackishouter ring. There is also a scaterring of smaller, all black, spots. A dark 'mask' is present across the eyesm, and a pair of larger circular or irregular dark brown blotches behind the spiracules. The underside is white. The tail has a bluish tinge, and has irregular black and white bands towards the tip.

Dorsal (a) and lateral (b) view of preserved Neotrygon romeoi holotype (CSIRO H 9640–06, female 379 mm disc width) from Tailevu Province, east Viti Levu Island, Fiji. Scale bar is 50 mm. Glaus et al. (2025).

Neotrygon romeo appears to be common around the islands of Fiji, and is found on various substrates, including sandy-bottom areas, seagrass beds, muddy-sandy areas with and without sea-grass, and coral reefs, from the tidal zone to depths of about 23 m. Individuals are generally solitary, but have been spotted in groups of up to five. Glaus et al. recommend that due to the species restricted range, high catch rate, and unknown life-history, it should be considered for legal protection by Fiji's Endangered and Protected Species Act, which con-serves biodiversity by regulating trade, protection and management of species at risk or endemic to Fiji.

Live colouration of Neotrygon romeoi from around Fiji: (a) Lautoka, mixed rocky and sand habitat. (b) Near South Sea Island, rocky reef. Drawaqa Island, Yasawas on sand flat with some seagrass in about 18 m of water. (d) Suva foreshore, on seagrass in about 20 cm of water. (e) Mana Island, over seagrass. Leon Perrie, Jack Crosbie, Robert Macfarlane, Tom Vierus, and Floyd Hayes in Glaus et al. (2025).

See also...

Magnitude 6.0 Earthquake to the north of Vanua Levu Island, Fiji.

The United States Geological Survey recorded a Magnitude 6.0 Earthquake at a depth of about 10 km, roughly 160 km to the north of Vanua Levu Island, Fiji, slightly after 4.10 pm local time (slighly after 4.10 am GMT) on Tuesday 15 September 2020. There are no reports of any damage or injuries relating to this quake, but it was felt on Vanua Levu.

  

The approximate location of the 15 September 2020 Fiji Earthquake. USGS.

The tectonic setting of Fiji is somewhat complicated. The islands form part of the border zone between the Pacific and Australian Plates, with the boundary passing to the north as a transform plate margin, along which the Pacific Plate is moving westwards, relative to Fiji. However, Fiji itself lies on an area of newly forming plate, with an are of expansion to its west, the Fiji Basin, which is pushing Fiji to the east relative to the Pacific Plate. Further to the west the Indo-Australian Plate is being subducted beneath this new microplate along the New Hebrides Trench. To the east of Fiji, a second area of seafloor spreading occurs along the Lau-Colville Ridge, and to the east of that the Pacific Plate is also being subducted, along the Tonga Trench. This means that the islands of Fiji are being subjected to tectonic stresses from several different directions. These stresses do not manifest themselves as smooth movements, but rather sharp jolts which we experience as Earthquakes, as the rocks of the various plates tend to adhere together, only breaking apart once the built-up pressures become to great, and settling into new positions.

 

Map and cross section showing the positions and movements of the tectonic plates around Fiji. Mörner & Matlack-Klein (2017).

 

Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organisation Earthquake Report is interested in hearing from people who may have felt this event; if you felt this quake then you can report it to Earthquake Report here.

See also...

Follow Sciency Thoughts on Facebook.

 

Magnitude 5.7 Earthquake to the north of Yasawa Island, Fiji.

The United States Geological Survey recorded a Magnitude 5.7 Earthquake at a depth of about 10 km about 10 km to the north of Yasawa Island, Fiji, at about 11.55 pm local time (about 10.55 am GMT) on Saturday 6 June 2020. There are no reports of any damage or injuries relating to this quake, but it was felt across much of the island nation.

The approximate location of the 6 June 2020 Fiji Earthquake. USGS.

The tectonic setting of Fiji is somewhat complicated. The islands form part of the border zone between the Pacific and Australian Plates, with the boundary passing to the north as a transform plate margin, along which the Pacific Plate is moving westwards, relative to Fiji. However, Fiji itself lies on an area of newly forming plate, with an are of expansion to its west, the Fiji Basin, which is pushing Fiji to the east relative to the Pacific Plate. Further to the west the Indo-Australian Plate is being subducted beneath this new microplate along the New Hebrides Trench. To the east of Fiji, a second area of seafloor spreading occurs along the Lau-Colville Ridge, and to the east of that the Pacific Plate is also being subducted, along the Tonga Trench. This means that the islands of Fiji are being subjected to tectonic stresses from several different directions. These stresses do not manifest themselves as smooth movements, but rather sharp jolts which we experience as Earthquakes, as the rocks of the various plates tend to adhere together, only breaking apart once the built-up pressures become to great, and settling into new positions.

Map and cross section showing the positions and movements of the tectonic plates around Fiji. Mörner & Matlack-Klein (2017).

Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organisation Earthquake Report is interested in hearing from people who may have felt this event; if you felt this quake then you can report it to Earthquake Report here.

 

See also...

 

Follow Sciency Thoughts on Facebook.

Three killed in Fiji landslide.

Three people have died following a landslide at a quarry operated by Island Quarries at Suva on the southeast coast of the island of Viti Levu, Fiji, on Friday 20 March 2020. The dead men have been identified as David Johnson, the managing director of the quarry, Seci Roko, the quarry manager, and Aporosa Ratu, a mechanic employed at the site. The event happened amid heavy rains and flooding associated with a low-pressure system that swept across the islands. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall.

Rescue workers with the remains of a vehicle crushed by a landslide that killed three people at a quarry in Fiji on Friday 20 March 2020. Two of the bodies were found adjacent to the vehicle. Fiji Sun.

Fiji has a tropical climate, with a wet season that runs from November to April, with peak rainfall in March, when over 360 mm of rain is usual, and a dry season that lasts from May to October. However, the dry season is not completely arid, typically still receiving about 150 mm of rain per month, and this year has been exceptionally wet, with some of the heaviest rain ever recorded in the islands falling in the past week, and local authorities are warning there is a danger of further landslips and flooding.

 The approximate location of the 20 March 2020 Suva landslide. Google Maps.

Low presure systems are caused by solar energy heating the air above the oceans, which causes the air to rise leading to an inrush of air. If this happens over a large enough area the inrushing air will start to circulate, as the rotation of the Earth causes the winds closer to the equator to move eastwards compared to those further away (the Coriolis Effect). This leads to tropical storms rotating clockwise in the southern hemisphere and anticlockwise in the northern hemisphere. These storms tend to grow in strength as they move across the ocean and lose it as they pass over land (this is not completely true: many tropical weather systems peter out without reaching land due to wider atmospheric patterns), since the land tends to absorb solar energy while the sea reflects it.

The low pressure above tropical storms causes water to rise there by ~1 cm for every millibar drop in pressure, leading to a storm surge that can overwhelm low-lying coastal areas, while at the same time the heat leads to high levels of evaporation from the sea - and subsequently high levels of rainfall. This can cause additional flooding on land, as well as landslides.

See also...

Follow Sciency Thoughts on Facebook.

Leptospirosis kills eight in FIji.

Eight people have now been confirmed dead in an outbreak of Leptospirosis  in Fiji that began in January this year (2019). Five people died in the January-April period, with a further three deaths reported over the Easter Period (19-22 April). At least 400 more people have been infected with the disease, which is principally contracted from animal urine, and can reach epidemic proportions when flooding occurs, as has happened in Fiji this year.

Flooding in Labasa, Fiji, in January 2019. The Fiji Times.

Leptospirosis is caused by a number of Bacteria in the genus Leptospira, Spirochaete Bacteria related to Borrelia burgdorferi (Lyme Disease) and Treponema pallidum (Syphilis). It typically manifests as a bout of severe fever, followed by several days of apparent recovery, then a second bout of fever which may be accompanied by meningitis and/or acute liver failure. The disease can be encountered worldwide, but in developed countries is rare except in those who work with livestock. However in areas of developing countries with poor sanitation outbreaks of Leptospirosisis can reach epidemic proportions during periods of flooding,

 SEM image of Leptospira interrogans, one of the causative agents of Leptospirosis. Janice Carr/Centers for Disease Control and Prevention/National Center for Infectious Diseases/Wikimedia Commons.

See also...

Follow Sciency Thoughts on Facebook.

Flooding kills at least four as Cyclone Josie sweeps past Fiji.

Four people are known to have died and one is still missing on Viti Levu Island, after Cyclone Josie passed to the south of Fiji on 1 April 2018. A 55-year old man has been found dead in Lautoka, a woman in Ba and two people in Nadi, where a 19-year-old man was seen to be swept away by floodwaters and has not yet been located. The area around Nadi has been particularly badly hit, with most of the town affected by flooding. The area received very little warning of the storm, which formed overnight around 120 km to the west of Kadavu Island, then passed to the south of the islands.

Flooding in the town of Nadi on Viti Levuiti Island, Fiji, after Cyclone Josie passed to the south on 1 April 2018. 9 News Australia/Facebook.

Tropical storms are caused by solar energy heating the air above the oceans, which causes the air to rise leading to an inrush of air. If this happens over a large enough area the inrushing air will start to circulate, as the rotation of the Earth causes the winds closer to the equator to move eastwards compared to those further away (the Coriolis Effect). This leads to tropical storms rotating clockwise in the southern hemisphere and anticlockwise in the northern hemisphere.These storms tend to grow in strength as they move across the ocean and lose it as they pass over land (this is not completely true: many tropical storms peter out without reaching land due to wider atmospheric patterns), since the land tends to absorb solar energy while the sea reflects it.

 The passage of Cyclone Gita till 6.00 am GMT on Sunday 1 April 2018  (thick line) with its predicted future path (thin line, circles represent the margin of error on the predictions). Colours indicate the strength of the storm. Tropical Storm Risk.

The low pressure above tropical storms causes water to rise there by ~1 cm for every millibar drop in pressure, leading to a storm surge that can overwhelm low-lying coastal areas, while at the same time the heat leads to high levels of evaporation from the sea - and subsequently high levels of rainfall. This can cause additional flooding on land, as well as landslides, which are are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall.

See also...

Follow Sciency Thoughts on Facebook.