World Malaria Day.

World Malaria Day is marked on 25 April each year, with the aim of raising awareness of both the disease and efforts to combat it. The day was originally adopted as Africa Malaria Day in 2001, following the signing of the Abuja Declaration at the African Summit on Malaria in 2000. This was adopted as an international observance at the 60th session of the World Health Assembly in 2007.

On World Malaria Day in 2026 the World Health Organization will be launching the campaign 'Driven to End Malaria: Now We Can. Now We Must.', which marks the fact that for the first time ever, ending Human Malaria is a genuine possibility. This includes the development of vaccines for Malaria, which are now being rolled out in 25 countries, as well as the development of genetically modified Mosquitoes which cannot spread the disease, improved Mosquito nets which are infused with dual action insecticides, seasonal chemoprevention measures which are now being offered to 54 million children in countries where Malaria is endemic, a widening of access to perennial (year round) chemoprevention, and better treatments for patients with Malaria.

Official World Malaria Day 2026 logo. World Health Organization.

Malaria is caused by parasitic unicellular Eukaryotes of the genus Plasmodium, and affects a wide range of terrestrial Vertebrates. Five different species of Plasmodium can cause Malaria in Humans, with most infections caused by either Plasmodium falciparum or Plasmodium vivax. The parasites are primarily spread via the bite of the female Anopheles Mosquitoes (males do not bite), but can also be spread through blood transfusions, organ transplants, or practices such as needle-sharing.

Photomicrograph of a blood smear containing a macro- and microgametocyte of the Plasmodium falciparum parasite. Both macro- and microgametocytes are products of the erythrocytic life cycle. Within a few minutes after the Anopheles sp. vector ingests the gametocytes, microgametocytes develop into microgametes, which are able to fertilize gametes. Centers for Disease Control and Prevention/Wikipedia Commons.

Malaria manifests with approximately 10-15 days after infection, as a fever, headache, and chills. Mild cases often pass soon, and can be difficult to identify as Malaria, however, more severe cases can be fatal in as little as 24 hours after the onset of symptoms. 

To date, 47 countries have been declared Malaria-free, with another 46 countries reporting less than 100 000 cases of locally acquired Malaria in 2024 (the last year for which reliable figures are available). Of those 46 countries, 37 reported less than 1000 cases, 26 reported less than 100 cases, and 24 reported less than 10.

Nevertheless, the situation is not all progress; 610 000 people died as a result of Malaria in 2024, an increase on the 598 000 who died in 2023. Four countries (Eritrea, Rwanda, Tanzania, and Uganda) have reported the emergence of strains of Malaria resistant to Artemisinin, the main treatment for the disease. Furthermore, 48 countries have reported Mosquitoes developing resistance to pyrethroid insecticides, which are the most commonly used to treat Mosquito nets hung over beds. Many strains of Malaria have also emerged which lack the pfhrp2 gene, which is used in diagnostic kits, delaying treatment in many cases. The Mosquito Anopheles stephensi, which is endemic to India, has been spreading in Africa in recent years. This Mosquito caries Malaria, and is a preferential urban-dweller, placing many people at greater risk.

Another serious threat is a massive shortfall in funding for Malaria programs, with US$5.4 billion in funding (more than half the total) being cut in 2025, with the United States, the United Kingdom, Germany, France, and Japan all making significant cuts to their aid programs. This has served to underline the fragility of aid programs which are reliant on the good will of a small number of wealthy donor countries.

Malaria eradication programs have also stalled due to civil conflicts and natural disasters, with major flooding events, which often co-occur with Malaria outbreaks, becoming more common due to the warming climate.

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Human Sleeping Sickness eliminated in Kenya.

The World Health Organization has officially confirmed that Kenya can be declared free of Human Sleeping Sickness (otherwise known as Human African Trypanosomiasis) in a press release issued on 8 August 2025. This is the second Neglected Tropical Disease to have been eliminated in Kenya, following the country being declared free of Guinea Worm, Dracunculus medinensis, in 2018, and makes Kenya the tenth country to be declared free of Human Sleeping Sickness. To date, 57 countries have been confirmed as having eliminated at least one of the seventeen recognised Neglected Tropical Diseases.

Human Sleeping Sickness is caused by a Protozoan, Trypanosoma brucei, which is an extracellular parasite infecting the blood plasma and other bodily fluids of its victims (unlike other parasitic Protozoans, such as the Malaria parasite Plasmodium spp., which infect the victim's cells). Trypanosoma brucei is a zoonotic infection, which is to say infection that affects Animals as well as Humans, and is typically carried by an Animal vector. This can create a reservoir of potential infectious agents in an Animal population, making such diseases difficult to eliminate. 

There are two subspecies of Trypanosoma brucei which infect humans, Trypanosoma brucei gambiense, which is found in West Africa, and Trypanosoma brucei rhodesiense, which is found in East and Southern Africa (and which was the form formerly found in Kenya). A third form, Trypanosoma brucei brucei, does not infect Humans, but can infect domestic Animals. All three known forms of Trypanosoma brucei infect a variety of Mammals (it is possible that other subspecies exist, but infect neither Humans nor domestic Animals, leading to their being overlooked), and are transferred from one host to another by the bite of the Tsetse Fly, Glossina spp.. Because of this, Humans involved in professions where they work closely with Animals, such as Animal husbandry or hunting, are particularly at risk of infection.

A smear of blood from a patient with Human Sleeping Sickness, stained with Giemsa (a histological stain which binds to areas of DNA with high levels of adenine-thymine bonding, making it useful for identifying parasitic organisms in blood), revealing two Trypanosoma brucei ssp. parasites. Centers for Disease Control and Prevention.

Because Trypanosoma brucei infections are not restricted to cells, the parasite is able to cross the blood-brain barrier with greater ease than most parasitic infections. The parasite breeds by binary fission, enabling its population within a host to increase exponentially. Once the population within the bloodstream become to high, the parasites begin to migrate within the body, frequently entering the cerebrospinal fluid and then the brain, where it caused Human Sleeping Sickness. As an Eukaryotic infection, Trypanosoma brucei is not vulnerable to antibiotics, and is typically treated with a form of chemotherapy which is also hazardous for the patient. As such, prevention of the disease is greatly preferable to treatment.

Human Sleeping Sickness was first recorded in Kenya in the early twentieth century, and has been the subject of strenuous control efforts ever since. A declaration of elimination for a disease is made at least ten years after the least recorded transmission of that disease within a country. In Kenya, the last reported case where the patient is believed to have contracted the disease within the country occurred in 2009, while the most recent reports of patients who are believed to have acquired the infection while out of the country (two patients) occurred in 2012. Despite this apparent success, Kenya has recently strengthened monitoring for Human Sleeping Sickness in counties where the disease was formerly endemic.

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Halamphora minima: A new species of Diatom from the mudflats of Hampyeong Bay, Korea.

Diatoms are single celled algae related to Kelp and Water Moulds. They are encased in silica shells with two valves. During reproduction the cells divide in two, each of which retains one valve of the shell, growing a new opposing valve, which is slightly smaller and fits flush within the older valve. This means that the Diatoms grow smaller with each new generation, until they reach a minimum size, when they undergo a phase of sexual reproduction, giving rise to a new generation of full-sized cells. The genus Halamphora was first described in 1895 as a subgenus of Amphora, but was elevated to a genus in its own right in 2009. It currently contains 154 species, with a global distribution, predominantly in marine and brackish water environments. Fifteen of these species have been recorded from Korea to date.

In a paper published in the journal Phytotaxa on 8 November 2022, Sung Min An of the Department of Microbial Resources at the National Marine Biodiversity Institute of Korea, Jihoon Kim of the Department of Biodiversity, also at National Marine Biodiversity Institute of Korea, and Nam Seon Kang, Kichul Cho, Jung Lee, and Fun Song Kim, also of the Department of Microbial Resources at the National Marine Biodiversity Institute of Korea, describe a new species of Halamphora from Hampyeong Bay, on the west coast of South Korea.

Samples were collected from an intertidal mudflat in Hampyeong Bay in July 2018, and cultured at the National Marine Biodiversity Institute of Korea. The recovered cells were then examined under light and scanning electron microscopes, with DNA being extracted to determine whether these Diatoms were a new species, and how they were related to other species within the group. The new species is named Halamphora minima, in reference to its small size in comparison to other members of the genus.

Map of sampling localities in Hampyeong Bay, the west coast of Korea. Type locality of Halamphora minima (35º03’41.94’’ N, 126º24’40.06’’ E). An et al. (2022).

The valves are only 5.9-7.4 μm in length and 2.4-3-3 μm in width, whereas most members of the genus exceed 15 μm in length, and the largest can exceed 80 μm. The tests of Halamphora minima have a deeply convex dorsal margin and a nearly straight ventral margin. The ventral side is expanded, and the valves on this size sealed by a series of striae. The raphe (a slit in the ventral edge of the shell) is straight on the and well developed. There is no axial longitudinal line on the dorsal edge. The surfaces of the shell are covered by a series of striae (lines) single on the ventral surface and double on the dorsal surface.

SEM micrographs of Halamphora minima. (11) External whole valve view, with central area (asterisk), and dorsal raphe ledge (arrow). (12) Internal whole valve view. (13) Detail of external valve apex,with dorsal raphe ledge (arrow). (14) Detail of internal valve apex showing tongue-like proximal helictoglossae (double asterisk), poorly developed distal helictoglossae (arrowhead), and internal longitudinal rib (arrow). (15) Detail of internal dorsal areolae occluded by hymens (arrows). (16) Dorsal girdle bands with two rows of poroids. (17) frustules showing the ventral girdle bands with dorsal raphe ledge (arrow). Scale bars: (11)-(14), (16), (17) 1 μm, (15) 0.5 μm. An et al. (2022).

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Aulacoseira wyomingensis: A new species of freshwater Diatom from a seep near Casper, Wyoming.

Diatoms are single celled algae related to Kelp and Water Moulds. They are encased in silica shells with two valves. During reproduction the cells divide in two, each of which retains one valve of the shell, growing a new opposing valve, which is slightly smaller and fits flush within the older valve. This means that the Diatoms grow smaller with each new generation, until they reach a minimum size, when they undergo a phase of sexual reproduction, giving rise to a new generation of full-sized cells. Members of the Family Aulacoseiraceae have elongate valves with many spines; these spines being able to  interdigitate with other members of the species, enabling them to form long chains. The family currently contains four genera, Aulacoseira, which is known from fossils dating back as far as the Cretaceous and still extant, with a global distribution, Eosira, which is known only from the Eocene of North America, Miosira, which is know from the Miocene of Europe, and Alveolphora, which is known from Miocene and Pliocene deposits across the Northern Hemisphere.

In a paper published in the journal Taxonomy on 8 June 2022, Jeremy Greifenstein, Rachel Shea, and John Patrick Kociolek of the Department of Ecology and Evolutionary Biology at the Museum of Natural History of the University of Colorado Boulder describe a new species of Aulacoseira from a small seep near Casper, Wyoming.

The new species is named Aulacoseira wyomingensis, where 'wyomingensis' means 'from Wyoming'. The new species is described from a series of specimens extracted from a sample collected on 22 August 2021. These Diatoms are cylindrical in shape, and while they can adhere together, chains of longer than two Diatoms have been observed.

Aulacoseira wyomingensis. Scanning electron microscopy. External girdle views of entire frustules. Valves have striae that are disorganised. Column has small ridges. Cingulum is composed of numerous ligulate elements. Spines are small in length and shield-like. Valve on the right in (C) appears to be incompletely formed. Scale bars are 5 µm. Greifenstein et al. (2022).

The valves of Aulacoseira wyomingensis are 7-14 μm in diameter, with faces covered by large areolae (openings) up to 1 μm in diameter. The sides are covered by striations, these having smaller areolae. The central part is covered by ridges. 

Aulacoseira wyomingensis. Scanning electron microscopy. Internal views. (A) Valve view showing areolae and interior of valve. Scale bar is 2.5 µm. (B) Side view showing part of valve interior and exterior. Scale bar is 2.5 µm. (C) Valve view of interior showing ringleiste. Scale bar is 2.5 µm. (D) High magnification view of single areola showing fine hymenate occlusion over opening. Scale bar is 0.3 µm. (E) Side view showing part of the valve interior and exterior. Scale bar is 2.5 µm. Greifenstein et al. (2022).

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Sleeping Sickness no longer considered a public health threat in Côte d'Ivoire.

Côte d'Ivoire has successfully eliminated Human African Trypanosomiasis, also known as 'Sleeping Sickness', as a public health problem, becoming the second African country after Togo to be validated by the World Health Organization, according to a press release isssued on 25 March 2021.

'I dedicate this milestone to decades of hard work and the individual contribution of every single health worker who braved some of the toughest challenges in reaching populations, often in remote rural areas,' said Eugène Aka Aouele, Minister of Health and Public Hygiene of Côte d'Ivoire. 'Our challenge now is to maintain the required level of surveillance and, with the help of everyone, to achieve interruption of transmission by 2030.' 

In the 1990s, Côte d'Ivoire reported hundreds of cases of Sleeping Sickness every year. Cases have progressively declined over the last 2 decades, and in the past few years, the country has reported fewer than 10 cases per year. At this low level, Côte d'Ivoire qualifies as having eliminated the disease as a public health problem. 

This achievement is attributed to robust control and surveillance measures, active (and passive) screening of people at risk, and targeted vector control, which helped to strongly decrease the number of cases in areas of transmission. Hospitals and health centres checked patients using specific diagnostic tests, while laboratory mobile units screened people in villages. 

 

A Human African Trypanosomiasis mobile unit in Côte d’Ivoire. CT Brink/World Health Organization.

'Côte d’Ivoire’s achievement marks an important step that brings Africa closer to eliminating Sleeping Sickness,' said Matshidiso Moeti, the World Health Organization's Regional Director for Africa. 'Sustained control measures over the past two decades have brought a significant decline in cases, a positive sign that many countries will soon be crossing this landmark.'

Treatment of infected people meant that the vector, the Tsetse Fly, Glossina sp., could no longer transmit the disease to others. This had to be maintained over years in order to progressively eliminate the disease.  

 

A Tsetse Fly, Glossina sp. International Atomic Energy Agency/Wikimedia Commons.

'The result which Côte d'Ivoire has achieved after several decades of fighting against Human African Trypanosomiasis, reflects the excellent leadership of the Ministry of Health and Public Hygiene through the Directorate of the Human African Trypanosomiasis Elimination Programme” said Jean Marie Vianny Yameogo, the World Health Organization's Representative in Côte d'Ivoire.” It is also the expression of the commitment and determination of the regional and departmental health directorates, health professionals, the communities' participation in control strategies and the vitality of the partnership.'

Two other countries, Benin and Equatorial Guinea, have submitted their dossiers to the World Health Organization, requesting validation for elimination of Sleeping Sickness as a public health problem. To achieve validation for the elimination of a public health problem, a complete dossier must be submitted to present detailed information on the past and present disease incidence throughout the territory. The country must show evidence of effective, ongoing surveillance to prove that the capacity of detecting the disease is strong. The figures must be below the specific thresholds required by the World Health Organization, which means one case per 10 000 inhabitants in all districts, during a five-year period.

Under the World Health Organization’s leadership, national control programmes, bilateral cooperation agencies and nongovernmental organizations have substantially reduced cases of the disease to unprecedented low numbers, specifically less than 1000 globally, before 2020.  

Sleeping sickness is a potentially fatal disease spread by the bite of an infected Tsetse Fly, which are native to the African continent. More than 60 million people living mainly in rural parts of 36 countries across East, Central and West Africa are at risk of contracting the disease.

The World Health Organization and partners are targeting the interruption of transmission of the Trypanosoma brucei gambiense form of the disease in all endemic countries by 2030. 

 

A blood sample showing infection with Trypanosoma brucei gambiense, the causative agent for African Sleeping Sickness. Public Health Image Library/Centers for Disease Control and Prevention/Wikimedia Commons.

The main approaches to controlling Sleeping Sickness include reducing the reservoirs of infection and reducing the presence of the Tsetse Fly.

Screening of people at risk helps identify patients during the early stage of the disease. If diagnosis is made early, it is possible to avoid complicated and risky treatment procedures during the advanced stage.

Human African Trypanosomiasis is a vector-borne parasitic disease caused by infection with Protozoan parasites belonging to the genus Trypanosoma. The causative parasite is transmitted to Humans through the bite of a Tsetse Fly which has acquired the infection from Humans or Animals harbouring the Human pathogenic parasites.  

 

The life cycle of the Trypanosoma parasite, the causative agent for African Sleeping Sickness. Centers for Disease Control and Prevention.

There are two forms of the disease: one due to Trypanosoma brucei gambiense, which is found in 24 countries in West and Central Africa and accounts for more than 98% of cases; and another due to Trypanosoma brucei rhodesiense, which is found in 13 countries in East and Southern Africa and accounts for the remaining cases.

When bitten by an infected Tsetse Fly, a red sore may erupt within a few weeks. The person may experience fever, swollen lymph nodes, aching muscles and joints, headaches and irritability.  

People who become infected feel lethargic and sleepy during the day, then awake but exhausted at night. This is followed by neuropsychiatric and sensory disorders, and then a coma. Death may occur within months or even years. 

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Mayamaea vietnamica: A new species of soil-dwelling Diatom from Vietnam.

The genus Mayamaea was proposed by Horst Lange-Bertalot in 1997. Initially, 13 taxa formerly attributed to Navicula sensu lato were included in the genus. Mayamaea includes small-celled species that are elliptical in shape. The main characteristic of the genus is the arrangement of the pore occlusions, which are hymenes that cover the areolae from the outside, as well as the presence of a pronounced sternum found in the vast majority of species. The location of the hymenes is an important characteristic that differentiates Mayamaea from the genera Eolimna and Sellaphora, otherwise these genera have much in common including the structure of the raphe, central pores and distal raphe ends. Therefore, accurate identification by morphological characteristics is possible only when studying the material using a scanning electron microscope. Currently, the genus has about 30 taxa. Species of the genus Mayamaea are distributed worldwide, though most species are known from Europe. The species Mayamaea agrestis was described from Southeast Asia (Indonesia).

Species of Mayamaea prefer humid terrestrial habitats, as well as freshwater ecosystems (oligotrophic and mesotrophic), including in the littoral zone of these environments. In discussing the ecology of the species, Carlos Barragán, Luc Ector and Carlos Wetzel suggest that soil habitats are typical for Mayamaea lacunolaciniata, Mayamaea muraliformis, Mayamaea terrestris, and Mayamaea petersenii. However, some other species have also been found in the soil. For example, Mayamaea atomus was found in the soil of paddy fields in Central Japan. A large number of Diatom species (147 taxa) were identified from cultivated soils in Podkarpacie Province, Poland, and the most numerous was Mayamaea atomus and 5 other species. Others species of Mayamaea were found as well, including Mayamaea agrestis, Mayamaea excelsa, Mayamaea permitis, Mayamaea cf econdita, and Mayamaea sp2. Jasper Foets, Carlos Wetzer, Adriaan Teuling, and Laurent Pfister found Mayamaea atomus as a dominant in the soil of the Attert River basin (Luxembourg). The authors revealed that Mayamaea agrestis was typically on agricultural grasslands, Mayamaea permitis was one of the most abundant species in the territory, and Mayamaea fossalis was found in undisturbed grassland soils.

In a paper published in the journal Algae on 21 December 2020, Elena Kezlya and Anton Glushchenko of the К.А. Timiryazev Institute of Plant Physiology, John Patrick Kociolek of the Museum of Natural History and Department of Ecology and Evolutionary Biology at the University of Colorado, Yevhen Maltsev and Nikita Martynenko, also of the К.А. Timiryazev Institute of Plant Physiology, Sergei Genkal of the Papanin Institute for Biology of Inland Waters, and Maxim Kulikovskiy, again of the К.А. Timiryazev Institute of Plant Physiology, describe a new species from the genus Mayamaea isolated from a soil sample from the territory of Cát Tiên National Park in Vietnam.

Cát Tiên National Park is located in southern Vietnam, 150 km northeast of Ho Chi Minh City. The park was established in 1978 and consists of three parts with a total area of 73 878 hectares (738.78 km²). The region belongs to the bioclimatic type of monsoon tropical climate with summer rains. Relative humidity, as a rule, always exceeds 70%, with an average annual temperature of about 26°C. From December to March there is almost no rainfall. Southwest monsoons last eight months, from April to November, when most of the precipitation is observed. The wet season peaks in August-September. At this time of the year, up to 400-450 mm of precipitation falls per month, which leads to flooding of a significant part of the park. The main part of the territory is occupied by forests, which are of the monsoon, semi-deciduous type. These forests are characterized by high biological diversity and high productivity, second only to moist tropical forests in this respect.

 

Geographical position of the studied area. Kezlya et al. (2020).

The sample used was collected on 9 June 2018 from the Cát Tiên National Park, Đồng Nai Province, Vietnam and designated No. 06460. It was comprised examof wet soil, which had a pH of 6.5. Samples in general were taken as follows: first, the surface of the test site was examined in order to detect macrogrowth of algae, then a combined sample was taken from an area of 10-30 m² using the metal scoop or shovel. The composite sample consists of 5-10 individual samples. For an individual sample, the topsoil was removed from an area of 5 to 20 cm². After selection, the instruments were cleaned and sterilised with ethanol. Samples were placed in plastic zip bags, labeled. Immediately after the selection, the absolute humidity was determined in the laboratory room by the 'hot drying' method, then air dried and packaged.

The new species is named Mayamaea vietnamica, in reference to the country where it was discovered, and the specimens were placed in the Collection of Maxim Kulikovskiy at the Herbarium of the К.А. Timiryazev Institute of Plant Physiology.

Under light microscope the cells are solitary, rectangular in girdle view. One H-shaped plastid, with one arm lying against each side of the girdle, connected by a narrow central isthmus. Valves small, from almost linear to elliptical and oval (29 specimens) with pronounced sternum and broadly rounded ends. Length 9.1-10.5 μm, breadth 3.9-4.8 μm. Raphe narrow, linear. Central area more or less expressed, rounded to asymmetrical, rarely transversally elongated, and bordered on each margin by 3 shortened striae and/or 3 isolated areolae. Axial area tapers from the central area, becoming narrower towards the ends. The striae are radiate throughout the valve, 19-22 in 10 μm. Areolae coarse, clearly visible in light microscope.

 

Mayamaea vietnamica Strain VP 1, slide No. 06460. Light microscopy, differential interference contrast. (A) & (C)-(Z) Valves face. (A)-(H) Live cells with chloroplast structure. (B) Сell in girdle view. (I)-(Z) Size diminution series. (K) Holotype. Scale bar represents: 10 μm. Kezlya et al. (2020).

Under scanning electron microscope in external view the raphe is narrow, linear. Proximal raphe ends straight, drop-shaped. Distal raphe fissures bending strongly to the same side of valve mantle. Striae composed in 1-3 round areolae, not extending to valve margin. Areolae round, covered by individual hymenes.

 

Mayamaea vietnamica. Strain VP 1, slide No. 06460. Scanning electron microscopy, external views. (A) & (B) Whole valve. Areola occluded by hymen (arrow). (C) Central area. (D) Valve end. Scale bars represent: (A) & (B) 1 μm; (C) & (D) 0.5 μm. Kezlya et al. (2020).

Under scanning electron microscope in internal view the raphe is narrow, linear. Proximal valve ends slightly deflected to one side. Distal raphe ends terminating in small helictoglossae.

 

Mayamaea vietnamica. Strain VP 1, slide No. 06460. Scanning electron microscopy, internal views. (A) Whole valve. (B) Central area. (C) & (D) Valves ends. Scale bars represent: (A) 1 μm; (B)-(D) 0.5 μm. Kezlya et al. (2020).

Phylogenetic analysis of molecular sequence data shows that Mayamaea vietnamica is part of a branch with other species of Mayamaea. The branch with Mayamaea species is well-supported and independent from other branches. Closely related to the monophyletic group of Mayamaea species is a branch with strains of species from the genera Sellaphora and Eolimna. The branch containing these genera also has high statistical support. Six strains of Mayamaea permitis are divided in two branches in Kezlya et al.'s molecular tree. This suggests the presence of at least two cryptic species from specimens whose morphology suggest they could be assigned to the taxon Mayamaea permitis sensu lato. Mayamaea fossalis is close to two strains of Mayamaea permitis, however a difference between these species is supported by high statistical support. This result shows that these two species are independent taxa based on Kezlya et al.'s molecular investigation.

 

Bayesian tree of Mayamaea vietnamica (indicated in bold) constructed from a concatenated alignment of 107 partial rbcL and partial 18S rDNA sequences of 1380 characters. Values above the horizontal lines are bootstrap support from RAxML analyses (those below 50 are not shown); values below the horizontal lines are Bayesian posterior probabilities (those below 90 are not shown). All sequences have strain numbers (if available) and GenBank numbers. Species from the centric diatoms were used as an outgroup. Asterisks represent 100% statistical support. Kezlya et al. (2020).

Mayamaea vietnamica possesses all of the typical characters of the genus Mayamaea. These features include hymenes that covers the areolae from the outside, uniseriate striae, large areolae, small size, as well as the presence of a pronounced sternum. Our new species is morphologically similar to some known species from the genus Mayamaea, but it differs from them by both quantitative and qualitative features. The results of Kezlya et al.'s molecular investigation show the new species is part of an independent branch the includes three taxa. Mayamaea vietnamica is more closely related to Mayamaea terrestris than either is to Mayamaea atomus. Additionally, Mayamaea permitis and Mayamaea fossalis were included in the molecular investigation. The lineage of Mayamaea taxa is part of a broader monophyletic group that includes species of the genera Sellaphora, Eolimna and Rossia. However, the results of Kezlya et al.'s molecular investigation show that there is high statistical support for recognising Mayamaea as a genus distinct from these other genera.

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