Boswellia hesperia: A new species of Dwarf Frankincense from Socotraa Island.

Frankincenses, Boswellia spp., are trees and small shrubs noted for the aromatic resin they produce, found in East Africa, Arabia, and parts of South Asia. In 1971 Frank Nigel Hepper of Kew Royal Botanic Gardens described a Dwarf Frnakincense, Boswellia nana, from the Yemeni island of Socotra in the Indian Ocean (a noted hotspot for botanical endemism). In 2004, botanists Anthony Miller and Miranda Morris reported a second species of Dwarf Frankincense from Socotra, something which several subsequent studies have also recorded, but which has not, to date, been formally described.

In a paper published in the Nordic Journal of Botany on 20 February 2025, Mats Thulin of the Department of Organismal Biology at Uppsala University, Michael Weber from Bad Berka in Germany, Sami Ali Mohammed Mubarak from Socotra Island, and Alain Rzepecky from São Brás de Alportel in Portugal, formally describe the second species of Socotran Dwarf Frankincense.

The new species is named Boswellia hesperia, where 'hesperia' means 'west', the species having been found exclusively at the western end of the Island of Socotra; this is in contrast to Boswellia nana, which is found exclusively at the eastern end of the island. Boswellia hesperia is an entirely prostrate dwarf species, found growing within holes and crevasses in limestone rock. This habit is also seen in Boswellia nana, although that species sometimes also produces dwarf shrubs up to 2 m high. Boswellia hesperiai also differs from Boswellia nana in its leaves, which are waxy above, but covered in white fur below, whereas those of Boswellia nana are waxy on both sides.

Boswellia hesperia from mountain ridge above Neet, 5–6 km from the coast, Socotra, 18 May 2021. (A) plant filling out crevice in limestone rock, leafless, showing reddish white flowers and fruits, (B) leafless plant with flowers and fruits. Alain Rzepecky in Thulm et al. (2025).

The total area over which Boswellia hesperia is found is about 63 km², however, the distribution of the species is patchy, and it probably is only found over an area of about 20 km². This limited distribution, along with the apparent risk of the species being overgrazed by Goats, leads Thulm et al. to recommend that Boswellia hesperia be classified as Critically Endangered under the terms of the International Union for Conservation of Nature's Red List of Threatened Species.

Boswellia hesperia, seedling flowering after about one and a half year in cultivation. Alain Rzepecky in Thulm et al. (2025).

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Numenius tenuirostris: The Slender-billed Curlew declared extinct.

The Earth's biodiversity is considered to be facing a crisis at a global level, with many experts believing that species may be going extinct at a rate as high as during the great extinctions recorded in the fossil record. Despite this, it is very hard to determine how many species are going extinct, in part because many species have never been documented, but also because it is generally impossible to tell whether a species is extinct, unless it can be confidently asserted that all populations were being monitored prior to extinction. The best recorded organisms tend to be Vertebrates, and one of the most extensively monitored Vertebrate groups are the Birds, a group which tend to be highly visible, and which are often recorded extensively by non-professional citizen-science groups. Despite this attention, many species of Birds have not been seen for a long time, and this cannot always be taken as evidence that they have become extinct: for instance, the Black-browed Babbler, Malacocincla perspicillata, was rediscovered in 2020 after not being observed in 180 years. The apparent extinction of species can be problematic, causing conservationists to cease efforts to protect a species which is close to extinction; conversely failure to realise that a species has become extinct can lead to efforts being dedicated to preserving it which could otherwise have been directed towards other species which might still be saved.

In a paper published in the journal Ibis on 17 November 2024, Greame  Buchanan of the RSPB Centre for Conservation Science, Ben Chapple of the Centre for Biodiversity and Environment Research at University College London, Alex Berryman of BirdLife International, Nicola Crockford of the Royal Society for the Protection of Birds, Justin Jansen of the Naturalis Biodiversity Center, and Alexander Bond of the Bird Group at the Natural History Museum, formally declare the Slender-billed Curlew, Numenius tenuirostris, to be extinct.

The International Union for the Conservation of Nature's Red List of Threatened Species currently lists the Slender-billed Curlew as Critically Endangered, on the assumption that the total population is less than 50 Birds and declining. The species is believed to be restricted to the Palaearctic biogeographical region, breeding in central Asia and migrating to Europe, North Africa, the Middle East, and the Arabian Peninsula. Slender-billed Curlews are thought to breed to the east of the Ural Mountains, in the area around Omsk in southern Russia. Isotope studies of museum specimens suggest that the species may also have bred further south, in northern Kazakhstan, while some eggs assigned to the species, also in museum collections, indicate that the species may also have bred to the west of the Urals. Outside of the breeding season the Birds ranged west as far as Western Europe and the Atlantic coast of North Africa, being known from across the Mediterranean Region, the Middle East, the Arabian Peninsula, and the Pannonian Plains of southeast Central Europe.

Once widespread in Europe, Slender-billed Curlews were last observed in Brittany, France, in February 1968, and in North Yemen in January 1984. A colony, thought to be the last, was known on the Atlantic coast of Morocco in the 1990s, with the last reported sighting in the winter of 1997/8, although a flock of Slender-billed Curlews was photographed in southern Italy in  March 1995. No subsequent observations of the species have been made, despite extensive searches across its former range, including the Middle East and Central Asia.

The last known photograph of a group of Slender-billed Curlews, taken in southern Italy in March 1995. Marco Basso in van den Berg (1995).

The Slender-billed Curlew was first observed breeding in 1912 by Russian ornithologist Valentin Ushakov, who first noted that the species appeared to be in decline. The possibility that Slender-billed Curlews might be at risk of extinction was first raised in 1943 by German ornithologists Erwin Stresemann and Hermann Grote, but it was not until 1988 that the species was identified as Threatened by the International Union for the Conservation of Nature. The species was listed as Critically Endangered in 1994, following a re-assessment of its status, and an action plan for its recovery was produced in 1996. 

Based upon this long absence from its known range, and the extensive, yet unproductive, searched which have been made in the last three decades, combined with the declining number of sightings recorded throughout the twentieth century, Buchanan et al. carried out a statistical analysis of the probability that the species might still exist. Based upon this, they conclude that is most likely that the species became extinct in the 1990s, with only a miniscule possibility that the species might still exist in the 2020s.

If this analysis is correct, then the Slender-billed Curlew is only the third species of Bird known to spend a large part of its annual cycle in the Western Palaearctic to have become extinct since 1500, joining the Great Auk, Pinguinus impennis, last reported in 1844, and the Canarian Oystercatcher, Haematopus meadewaldoi, last observed in 1913. 

A preserved museum specimen of a juvenile male Slender-billed Curlew, Numenius tenuirostris. Naturalis Biodiversity Center/Wikimedia Commons.

It is difficult to directly assess the cause of the extinction of the Slender-billed Curlew, since it is likely that the species finally died out around the time that an action plan for its survival was first drawn up. When that plan was produced, it identified that the species was threatened by habitat loss across its range, and potentially being hunted in some areas as well. 

The only records of breeding by the Slender-billed Curlew are those made by Valentin Ushakov in southern Russia in the early twentieth century. It is possibly that the main breeding area for the species was further south, on the steppes of northern Kazakhstan, which were extensively converted to croplands by the Russian Empire and Soviet Union in the nineteenth and twentieth centuries, in the process destroying extensive wetlands, which might have served as breeding grounds for Slender-billed Curlews, however, without further evidence, this is purely speculative. 

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New reports of Leopard-hunting in Yemen.

The Arabian Leopard, Panthera pardus nimr, is a subspecies of Leopard endemic to, and once found across, the Arabian Peninsula, but now considered to be Critically endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species, with less than 200 Animals thought to be surviving in Oman, Yemen, and possibly Saudi Arabia, although the species hasn't been seen in Saudi Arabia since 2014. Oman is thought to have a steady population of about 50 Leopards, where the species is protected, but the situation in Yemen is less clear. Leopards are known to be hunted in the south and southeast of Yemen, where there is an ongoing civil conflict, and Leopard killings in Lawdar in Abyan, north of Lahij and Ad Dali, have been reported since 2021.

In a letter published in the journal Orynx on 22 May 2023, Hadi Al Hikmani of the Royal Commission for AlUla, and Andrew Spalton of the IUCN Species Survival Commission Cat Specialist Group, discuss new reports of the hunting of Arabian Leopards in the Hawf Mountains of eastern Arabia.

The Hawf Mountains are outside of the conflict zone in Yemen, lying close to the border with Oman. The killing of two Leopards was reported here in 2014, but there have been known further instances for almost a decade. In November 2022 images of a Leopard killed in the Hawf Mountains in response to livestock losses appeared on social media sites, with reports of a second Animal apparently killed for similar reasons, appearing in January 2023.

An Arabian leopard, Panthera pardus nimr, caught on a camera trap in Dhofar, southern Oman. Hadi Al Hikmani in Al Hikmani and Spalton (2023).

Killing in response to the taking of livestock, whether real or perceived, is considered to be the major reason for the decline of the Arabian Leopard across the entirety of its range. In Oman and active program of interventions has largely ended such persecution of the species, but this is not the case in Yemen, raising concerns about the future of the species there. The apparent resumption of Leopard hunting in the Hawf Mountains, far from the country's conflict zone, is particularly troubling, as the population here is thought to be small, and could easily be wiped out quite quickly.

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Odontochrydium arabicum: A new species of Cuckoo Wasp from the Arabian Peninsula.

Cuckoo Wasps, Chrysididae, are a widespread and diverse group of Wasps, noted for their kleptoparasitic habits; that is to say that, like many Wasps they lay their eggs inside the paralized bodies of other Insects and Arachnids stored in nests, but unlike these Wasps they do not catch their own prey, but rather lay their eggs inside the victims of other parasitic Wasps, the Cuckoo Wasp larvae then eating both the prey and the larvae of the original Wasp. The genus Odontochrydium currently contains three species of Cuckoo Wasps, two from sub-Saharan Africa and one from southern India.

In a paper published in the journal Zootaxa on 18 February 2022, Ahmed Soliman of the Plant Protection Department at King Saud University and the Zoology Department at Al-Azhar University, Paolo Rosa of the Laboratoire de Zoologie at the Université de Mons, and Hathal Dhafer, also of the Plant Protection Department at King Saud University, describe a new species of Odontochrydium from the southern Arabian Peninsula.

The first reported example of a Wasp of the genus Odontochrydium was a female collected from the Asir region of Saudi Arabia in 2015, and identified as a member of the species Odontochrydium bicristatum, which is otherwise known only from East Africa. However, since this report other specimens collected in southern Saudi Arabia, Oman, and Yemen have come to light, including several males (which show greater differentiation between species than is seen in the females), leading Soliman et al. to conclude that the Arabian population is in fact a different species to the East African population.

The new species is named Odontochrydium arabicum, where the specific name 'arabicum' refers to the Arabian Peninsula. The species is described from ten specimens, four males and six females, collected from the Asir and Jazan regions of Saudi Arabia, the Dhofar Governate of Oman, and Yemen.

 

Odontochrydium arabicum, male, holotype. (A) Habitus, lateral view; (B) Habitus, dorsal view; (C) Habitus, ventral view. Scale bar is 1.0 mm. Soliman et al. (2022).

Males and females of Odontochrydium arabicum are bright green with copper shimmering when alive, but turn a dark metallic blue after death. Both sexes have covering of fine white hairs, and tiny pits. The eyes are also white. Adult Wasps reach about 5.2 mm in length.

 

Odontochrydium arabicum, female, paratype. (A) Habitus, lateral view; (B) Head, frontal view; (C) Mesosoma and T1, detail; (D) T2–T3. Scales is 1.0 mm. Soliman et al. (2022).

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Emerging Locust swarms threaten further food insecurity in East Africa and the Arabian Peninsula.

The Food and Agriulture Organisation's Locust Watch Program has issued a warning that several new Desert Locust, Schistocerca gregaria, swarms are emerging in northern Kenya, southern Ethiopia, Somalia and Yemen, threatening further food insecurity in the region. The area has already been suffering the worst Locust outbreak in 70 years, leading to the destruction of crops across Ethiopia, Somalia, Kenya, Djibouti, Eritrea, Tanzania, Sudan, South Sudan, Uganda, Yemen, Oman and Saudi Arabia, but the agency has warned that the Insects are breeding rapidly in remote areas where there is little oportunity for aerial spraying, the most effective way of controlling them, and that populations emerging now would be likely to swarm in June, which is peak crop growing time in the region. 

A swarm of Desert Locusts, Schistocerca gregaria, in Isiolo county, Kenya. Sven Torfinn/AP.

Desert Locusts typically have two or three generations in a year, but when conditions are favourable then five or more generations can occur. The females lay eggs in an ootheca (egg sack) in soft sand, where they can remain dormant until conditions are favourable or hatch within a few days. Hatchlings can reach maturity in about five weeks, eating as much as one-and-a-half times their body weight each day, when they are potentially able to breed again.

 A swarm of Locusts in the Somali Region of Ethiopia. Giulia Paravicini/Reuters.

The adult form of the Desert Locust has two forms, the more usual solitary form, which does not usually move far from the area where they emerge, and a gregarious form, which forms large swarms and can roam long distances. The change from solitary to gregarious Locusts can happen in individuals, which change from one to the other in response to a rise in population density, but the reverse, a change from gregarious to solitary Locusts, can only happen when a new generation reaches maturity.

Solitary (top) and gregarious (bottom) Desert Locust nymphs. Compton Tucker/NASA/Goddard Space Flight Center/Wikimedia Commons.

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Landslides kill at least 32 in the Oromia Region of Ethiopia, as Cyclones batter the Horn of Africa and the Arabian Peninsula.

At least 32 people have died in a series of landslides in the Oromia Region of Ethiopia this weekend, with the worst incidents occurring in Gamo Gofa, where a landslide killed nine people and injured seventeen, and Sidama, where a landslide killed 23 people and injured six. The events happened amid heavy rains that have brought widespread flooding and related problems to East Africa, associated with cylones Sagar, which has been attributed with the deaths of 49 people in Somalia (where an ongoing civil conflict has hampered relief efforts) and two in Djibouti (where as much rain fell in 24 hours as usually falls in a year) and Mekunu, which is attributed with seven deaths in the Socotra Islands (Yemen) and six in Oman, with eight sailors still missing on two vessels in the region. Landslides 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.

 The aftermath of a landslide at Sidama in the Oromia Region of Ethiopia, which killed 23 people on Saturday 27 May 2018. Atnaf Brhane/Twitter.

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 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.

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