Tracing the origin of Azobé wood from Cameroon, Gabon, and the Republic of Congo.

Illegal logging is a serious problem in many of the world's forests, damaging ecosystems, undermining sustainable management practices, and fuelling other forms of crime. It has been estimated that between 8% and 29% of all internationally traded timber has been harvested illegally, which would make the illegal trade in wood the world's third largest form of trans-border crime. This problem is particularly acute in tropical regions, for example the proportion of internationally traded timber from Central Africa thought to have been taken illegally is thought to be between 50% and 90%. Many timber importing countries have legislation which require importers to show that timber has been sourced legally, with data on both the origin and species of wood required, but this is often difficult to prove, and current international trade systems are thought to be rife with abuse. The new European Union Regulation on Deforestation Free Products, which is due to come into effect on 30 December 2025, mandates that timber importers demonstrate that timber has been sourced legally, and in a way that does not contribute to deforestation, and also requires that exact geolocations are provided for each piece of timber. However, independently verifying both the species of tree from which wood originates and the location from which it was obtained is likely to prove challenging.

A variety of methods have been used to try to verify the origins of timber, including the anatomy of the wood, genetic identification, near-infrared spectroscopy, mass spectroscopy, and stable isotope analysis. These methods have proven effective in identifying wood to the species level, but much less effective at determining its point of origin, leaving tracing efforts reliant on external documents, tags, or scans, all methods which are known to be vulnerable to fraudulent practices. Methods such as genetic analyses, stable isotope ratios and multi-element analysis, have failed to achieve the level of accuracy needed to track tropical timbers effectively, at least in part because of a lack of variation between samples.

In a paper published in the journal Communications: Earth & Environment on 15 October 2025, a team of scientists led by Laura Boeschoten of the Forest Ecology and Forest Management Group at Wageningen University & Research, and the Department of Ecology, Evolution and Environmental Biology at Columbia University, and Barbara Rocha Venancio Meyer-Sand also of the Forest Ecology and Forest Management Group, and of the Forest and Nature Conservation Policy Group at Wageningen University & Research, describe a multi-variant method which combines genetic analysis, stable isotope ratio analysis, and multi element analysis to trace the origin of Azobé, or Red Ironwood, Lophira alata, timber from locations in Cameroon, Gabon, and the Republic of the Congo. 

Azobé logs from Gabon. WoodPro Industries.

Boeschoten and Meyer-Sand et al. reasoned that these different methods can present complementary information when trying to determine the origin of wood, and note that similar methods have been used to trace a range of agricultural commodities, wood from archaeological sites, and timber from temperate forests. Central Africa presents an ideal test area for the use of these methodologies in a tropical context. Levels of illegal logging are known to be high, there is an absence of the type of geographical barriers which lead to genetic isolation, and limited variations in climate, topography, bedrock, or soil type, all of which tend to hamper single-method tracing, but which leave open the possibility of multi-technique methodologies providing sufficient data to allow for accurate tracing of wood samples. To this end, Boeschoten and Meyer-Sand et al. combined genetic, isotopic, and elemental tracing methods, to evaluate if, in concert these could provide a reliable method to trace timber from Central Africa.

For trees, a genetic landscape can often be determined through the distribution of genetic traits within a population, which in turn is determined by reproductive, demographic and historical biogeographic factors, such as seed and pollen dispersal, topographic barriers like rivers and mountain ranges, and evolutionary history, including glaciation cycles during the Pleistocene that led to forest refugia. Genetic methods have been used to determine the origin of timber on a regional scale, for example to differentiate between West African and West African timber, and has sometimes proven useful at identifying the country of origin for wood, with a few cases of the method being used to differentiate timbers at shorter ranges. 

Stable isotope ratios represent the proportion of isotopes such as oxygen¹⁸, hydrogen² (deuterium), carbon¹³, nitrogen¹⁵, and sulphur³⁴ within the total samples of their respective elements from a sample. While these isotopes have the same chemical properties as the more common isotopes of the same elements, they have different masses, and therefore are subject to sorting by some biological, geological, and environmental processes. This method has been used extensively in timber tracing from other regions, and has proven effective as a way of differentiating timbers from locations very distant from one-another, with a higher spacial definition achieved in areas where local isotopic variations tend to be larger, such as in mountain ranges. This method is often combined with element analysis. In Central Africa, some studies have found this to be an effective way to tell timber from different locations apart, but in other areas little difference has been seen between remote locations within the same country.

Multi-element analysis works by measuring the proportions of elements such as magnesium, calcium, and lanthanum in wood samples. These elements are not vital for the survival of trees, but are taken up with ground water during transpiration, then deposited into the tissues of the plant. The proportion of each of these elements present reflects the chemistry of the soil and underlying bedrock. This method can be quite efficient at differentiating the origin of timber over small distances, but is less accurate over larger areas. It has been combined with stable isotope analysis to determine the origin of some timbers from Eastern Europe.

Azobé timber is widely traded in the Congo Basin due to its dense, durable, and decay-resistant wood, which can be used for structures such as roads and jetties. The species is listed as Vulnerable on the International Union for the Conservation of Nature's Red List of Threatened Species, due to heavy harvesting of the trees, destruction of the forests where they grow, and a slow growth and regeneration rate. Boeschoten and Meyer-Sand et al. sampled 234 Azobé trees at 23 locations in Cameroon, Gabon, and the Republic of Congo, with the two closest sites being 15 km apart, and the two most remote separated by a distance of over 1000 km. Samples were tested for chloroplast genome-wide single-nucleotide polymorphisms (individual gene variations from chloroplasts, which do not undergo genetic recombination each generation, but are inherited from the mother Plant in the same way as mitochondria), the proportions of the isotopes oxygen¹⁸, hydrogen², and sulphur³⁴, and the presence of 41 elements, including trace elements known to be used by plants as well as 16 rare earth elements.

Overview of the three methods for timber tracing in this study and their drivers of geographic variation. Possible drivers of geographic variation shown as examples are: (1) For single-nucleotide polymorphisms (SNPs): former forest refugia during cold Pleistocene glaciation cycles with refugia in dark and forest cover in light green. (2) For stable isotopes: the oxygen isotope signal in rainwater, with higher rainwater the proportion of oxygen¹⁸ in lighter blue. (3) For multi-element analysis: soil clay content ranging from high clay % in green, mid-levels of clay % in yellow and low clay % in pink. Boeschoten & Meyer-Sand et al. (2025).

The primary focus of the study was to address origin identification ('Where did this timber come from?'), with origin verification ('Does this timber come from the stated place of origin?') being a secondary question. Origin identification is considered to be a crucial step in the creation of forensic methods, as it gives insight into variation across different points of origin, and is therefore the most widely used metric in studies; making this essential to compare the value of one particular study to those carried out by other research groups. However, Boeschoten and Meyer-Sand et al. note that origin verification is the more common goal of forensic studies, so both aims were included in the study.

The genetic analysis identified three main genetic clusters, as well as recovering previously identified genetic splits, including one which divides the Lower Guinean Region, and another that follows the Cameroonian Volcanic Line. The largest of these three clusters incorporated ten sites in West Cameroon, to North￾West Congo and Central-East Gabon, with two sites in West Cameroon forming a distinct sub-cluster. The second cluster was located in West Gabon, and was the most genetically distinct, potentially representing an unknown cryptic species of Lophira. The third group was located in the Northern Congo, and again represents a distinctive, and previously unknown genetic population, although in this case probably not distinctive enough to merit being identified as a separate species. 

Despite this apparent distinctiveness, genetic analysis of individual samples was only able to place them at the correct site of origin 46.2% of the time, with 62.2% of trees identified to a location within 100 km of where they grew and 85.6% to within 300 km. All trees were placed within 500 km of their growing sites.

An Azobé tree growing in Cameroon.  Biwolé et al. (2019).

Stable isotope ratios were found to vary a great deal, with the variation between trees at the same site often as great as that between trees at sites hundreds of kilometres away. Some patterns could be observed, particularly with regard to hydrogen², but even when all isotopes examined were included, it was possible to identify the site of origin for a sample only 40.7% of the time, and to place a tree within 100 km of its location only 49.8% of the time. Trees were frequently placed more than 1000 km from their actual location.

Levels of trace elements varied from between 0.001 g per kg for ytterbium and 4 g per kg for potassium. There were clear differences between sites, and trees could be placed at the correct site 73.4% of the time, and within 100 km 81.3% of the time. The elements tungsten, barium, molybdenum, potassium, and chromium were most useful in determining sample origins. Trees could be placed accurately at two sites in Cameroon 100% of the time, although some trees from other sites were still misplaced by more than 1000 km. 

Confusion charts for the identification of wood samples to their respective origin. Identification was based on (A) single-nucleotide polymorphisms (SNP), (B) three stable isotope ratios (ISO), and (C) multi-element analysis of 44 trace elements (EL) and D all three combined. Mean identification accuracy across all sites is indicated in the bottom left. Each site has a unique colour, shown in the inner circle and in the legend. Colours in the outer circle of each symbol indicate to which (other) site(s) the trees of that site were assigned. Primary tropical forest extent from Global Forest Watch is indicated in grey. Boeschoten & Meyer-Sand et al. (2025).

Combining any two of these methods proved to be more accurate than any method on its own, confirming that using a combination of methods was a valid approach. Combinations which included the multi-element analysis were particularly efficient, with a combination of multi-element analysis and single-nucleotide polymorphic genetic analysis placing trees at the correct site 79.8% of the time, while a combination of multi-element analysis and stable isotope analysis achieved this 77.3% of the time. When all three methods were combined, trees were placed at the right site 86.9% of the time, within 50 km of that site 91.0% of the time, and within 100 km of that site 94.5% of the time. When all three methods were used in combination, no tree was placed more than 500 km from its site of origin. Individual sites varied in the method which showed the most accuracy, with some sites being identifiable using only a single method. Notably, however, some sites which did not achieve high levels of accuracy with any single method achieved 100% accuracy with a combination of the three.

The combination of methods used by Boeschoten and Meyer-Sand et al. compares well to previously tried methods when attempting to identify the point of origin of samples. However, the question most commonly asked by forensic scientists working with timber-trade regulators is not 'Where did this timber come from?', but 'Does this timber come from where it is supposed to come from?'. In order to assess this, 41 samples were removed from the dataset, which was then recalibrated without them. Each sample was then tested against two claims, firstly that it came from the site that it genuinely came from, and secondly that it came from a randomly chosen alternative site. In this second scenario, all trees from the same site as the tree being tested were excluded, to simulate a tree from a genuinely unknown source, which would not be present in the database.

In the scenario where samples were tested against the correct site of origin, the test identified the sample correctly with an accuracy of 87.8%, whereas for the second test, testing a sample against an incorrect point of origin, the correct answer was produced 95.4% of the time. A purely random test would have identified samples from the correct site only 7.7% of the time, whereas it would have excluded samples from the wrong site 91.7% of the time. Thus, while the second test appeared more accurate, it was not a notable improvement on random chance.

Origin fraud is a major problem for the international timber industry, and no testing method has proven to be completely reliable in all settings. Regions such as Central Africa, where there are few geographical barriers and little environmental variation, are particularly problematic. By using three different methods together, Boeschoten and Meyer-Sand et al. were able to reach a level of tracing accuracy better than had previously been obtained for the region, with 94.5% of wood samples assigned within 100 km of their origin and 91% within 50 km. When the method was used to test timber against claimed points of origin, it correctly confirmed true claims 87.8% of the time and rejected false claims 95.4% of the time.

The 800 m-long Blauwe Loper Bridge in the Netherlands is Europe's longest cycle bridge. It was constructed using Azobé wood from Forest Stewardship Council certified sources. The durable nature of the wood means that it is predicted that it will not need to be replaced for 80 years. About 450 tonnes of Azobé wood was used in the construction of the bridge. Fair & Precious.

Combining the three methods provided a greater level of accuracy than using any single method. This is because each variable is driven by a different set of conditions, resulting in a higher level of differentiation, even in a relatively homogeneous environment. The technique was particularly good at placing samples within 50 km of their point of origin compared to other methods, which corresponds roughly to the scale at which soil properties vary. The inclusion of genetic data considerably improved the resolution achieved, even though the lack of geographical barriers resulted in only a gradual genetic change between the sites. 

The method compared well to previous studies which have only used a single technique to try to identify timber from the region, and Boeschoten and Meyer-Sand et al. anticipate that methods using multiple different forms of analysis will prove to be useful in areas where environmental gradients are low, but high resolution testing is required. Legal requirements around sourcing timber sustainably are likely to tighten in consumer countries in the future, which will require more reliable methods of testing claims about the origin of timber, as well as for commodities such as palm oil, soy, rubber, beef and cocoa. The methods chosen to verify the origin of such commodities will likely vary, but for items such as timber from the Congo Basin, where fraud is considered to be a significant problem, testing methods will need to be demonstrably reliable with a high degree of accuracy.

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Zorotypus komatsui: A new species of Ground Louse from Cameroon.

Ground Lice, Zoraptera, are small (less than 3 mm) Insects typically found under bark. They are one of the smallest orders of Insects, with only 46 described species, although this may be a severe underestimation of their true diversity, as they are both easily overlooked and morphologically conservative. Ground Lice have a fossil record dating back to the Palaeozoic, with the last common ancestor of all living species thought to have lived about 270 million years ago. They are mostly wingless, and were once thought to be so throughout their life-cycle (the name Zoraptera means 'pure wingless') but winged forms are produced at some times of year, helping them colonise new areas.

In a paper published in the journal ZooKeys on 1 September 2023, Yoko Matsumura of the Department of Ecology and Systematics at Hokkaido University, Munetoshi Maruyama of the Kyushu University Museum, Nelson Ntonifor of the Department of Agronomic and Applied Molecular Sciences at the University of Buea, and Rolf Beutel of the Entomology Group at Friedrich-Schiller-Universität Jena, describe a new species of Ground Louse from Cameroon.

The new species is described from a single wingless male specimen discovered under a 30 cm long rock half embedded in soil close to the village of Nyasoso in Southwest Region, Cameroon, by Takashi Komatsu and Munetoshi Maruyama. A subsequent search of the surrounding forest yielded no further specimens. It is placed in the genus Zorotypus, and given the specific name komatsui; no explanation is given for this name, but it presumably honours Takashi Komatsu. The single known specimen of Zorotypus komatsui is a wingless male, 2.42 mm in length, with a head 0.47 mm long and 0.50 mm wide. It is light brown in colour, lacking any markings, even eye spots. 

Digitalmicroscopic images of the holotype of Zorotypus komatsui (ventral view) (A) habitus, (B) head and prothorax, (C) hindleg and abdomen. Matsumura et al. (2023).

Matsumura et al. also report the presence of Zorotypus vinsoni, a species previously known only from Mauritius, on Madagascar. This is the second species found to be present on both islands, following Zorotypus delamarei, which was discovered initially on Madagascar and subsequently on Mauritius. Mauritius was formed by volcanic activity about 8.9 million years ago, and probably largely resurfaced by another volcanic episode about 1 million years ago. This being the case, it is likely that both species of Zorotypus found on Mauritius have colonised the island from Madagascar in the recent past.

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Investigating ancient burials in western Africa.

The organised disposal of the dead is considered to be an important step in the development of Human cognition, an activity driven by the needs of the living to cope with the loss of a loved one, rather than any need of the deceased. In Africa, the earliest burials appear about 90 000 years ago, and are generally of single people thought to have been buried by nomadic or semi-nomadic peoples, with notable examples at Taramsa I in Egypt (about 55 000 years old), Shum Laka in Cameroon (7100-6900 and 3300-3000 years old), Mbi-Crater, also in Cameroon (about 7790 years old), Wadi Kubbaniya in Egypt 19 000-17 000 years old), Amekni in Algeria (9000-8000 years old), Ti-n-Hanakaten, also in Algeria (about 6000 years old), and Iwo Eleru in Nigeria (16 000-11 000 years old). These are eventually replaced by the emergence of formal cemeteries, about 25 000-23 000 years ago, in which the dead are buried together at sites dedicated to the purpose, thought to be a sign of people living together in settled communities, with notable examples at Mechta el Arbi in Algeria (22 000-13 000  years old), Afalou Bou Rhummel, also in Algeria (12 450-10 500 years old), Columnata, again in Algeria (8300-7300 years old), Taforalt in Morocco (15 100-14 000 years old), and in northern Sudan (14 340-13 140 years old).

In a paper published in the Journal of Anthropological And Archaeological Sciences on 20 December 2021, Augustin Holl of the Department of Anthropology and Ethnology at Xiamen University explores the Iwo Eleru, Amekni, Ti-n-Hanakaten, and Shum Laka burial sites, and what these can tell us about the people buried there, and the people who buried them.

 

Location of the sites discussed. (1) Iwu Eleru. (2) Amekni. (3) Ti-n-Hanakaten. (4) Shum Laka. Holl (2021).

The Iwo Eleru Rock Shelter in southwestern Nigeria (modern Ondo State). The site was first excavated in the 1960s by a team led by Thurstan Shaw, revealing a Human skeleton in a tightly crouched position between two large collapsed stone slabs. The skeleton was poorly preserved, but is thought to have been a man between 35 and 45 years of age at the time of death. The teeth of Iwu Eleru Man were very badly worn, ground down to the gums in a series of great sweeping oblique curves running in different directions. Damage of this kind can be caused by certain forms of craft-working, notably basket or Reed-mat making, or by eating extremely fibrous foods, such as raw and sometime sandy fibrous tropical tubers. The body was covered by about 1.5 m of sediment, containing numerous lithic artefacts, notably quartz and chalcedony segments, borers, scrapers, trapezes, trapezoïds, points, and truncated blades. Towards the top of this sequence pottery fragments and ground stone axes appear, although there are no obvious stratigraphic breaks in these deposits.

The deposits above the burial indicate that the site continued to be used by living Humans after the burial, although probably not continuously. The site is likely to have been repeatedly used as a shelter by non-settled peoples passing through the area, perhaps seasonally, with the burial being placed there because a member of the community died while they were staying there. No grave goods were found, but the body was covered over by two large stone slabs, and possibly leaves, twigs, and tree branches, which implies some form of ritual, and a desire to protect the body from scavenging by wild Animals.

 

View of Iwo Eleru rock-shelter. Holl (2021).

The Amekni burial is in a granite boulder field to the southwest of the Ahaggar Mountains of southern Algeria. The area is known to have been inhabited by pottery-making foragers between 7000 and 6000 BC, and these are thought to be the people responsible for the burial. Three skeletons were found at this site, a woman thought to be 40-50 years old, and two children aged roughly 2-3 and 5-6, who were buried in a crouched position, and possibly wrapped in Animal skins. The woman is probably two old to have been the children's mother, though she could possibly have been their grandmother. This does not appear to have been the beginnings of an organised cemetery, but rather the burial of three members of a mobile community, and possibly the same family, who died at approximately the same time and were therefore buried in the same place.

The Ti-n-Hanakaten rock shelter is located at the junction of the Tadrart Acacus and Tassili-n-Ajjer mountains, about 150 km to the southeast of the town of Djanet. The site has a Epipalaeolithic archaeological sequence about 5 m thick, which spans about 20 000 years and records the advent of pottery in the area, as well as a scattering of Acheulean artefacts (an Old Stone Age technology, associated with Homo erectus rather than Modern Humans). The site produced a single burial, a child of uncertain age, who was buried in a tightly crouched position, wrapped in an Animal skin, within a circular pit filled with grass and straw, and sealed with a large stone slab, which had been smeared with red ochre. The Ti-n-Hanakaten burial has been dated to about 6000 years old, making it a similar age to the Amekni burial, with which it shares some similarities; in both cases children were buried in crouched positions and wrapped in Animal skins. However, the Ti-n-Hanakaten burial is more elaborate than the Amekni burial.

The Shum Laka rock-shelter is located in the volcanic highlands of northwestern Cameroon, at an altitude of 1600 m above sealevel, overlooking the Laka Valley. The rockshelter is located at the foot of a waterfall, and measures roughly 54 m by 25 m, with a floor surface of about 1181 m², of which 82 m² has been excavated, and an 8 m high roof.

The site has yielded four distinct archaeological units, ranging in age from 32 000 to 3000 years. There are two sets of burials here, both associated with Holocene layers, the older dating from 7100-6900 years ago with four sets of remains in three burial and the younger from 3300-3000 years ago with fourteen sets of remains in nine burials. This larger clustering of burials raises the possibility that the people here might have been moving towards the organised burial of their dead in permanent cemeteries set aside for this purpose.

 

View of Shum-Laka rock-shelter. Holl (2021).

The earlier phase contains three burials at the northwest of the excavated area. The first of these is a man of about thirty with moderate osteophytosis on some vertebrae, some inflammation of the limbs, and two healed fractures, on the clavicle and left humerus, as well as dental calculus and heavy wear to the canine teeth, something which is almost certainly associated with some form of craftwork. His death appears to have been due to the cumulative effects of illness and old age, and his remains have been dated to about 7040 years ago. He was buried bout 8 m from the entrance to the cave, laid on the bedrock and covered with stones (in a similar fashion to the Iwu Elero burial), and covered by about 80 cm of sediment. The skeleton was in a sleeping position on its right side, with hands under the head, fcing towards the entrance of the shelter. 

The second early phase burial is locater 3 m south of the first, and 5 m from the entrance. It contains two sets of remains, a boy of about four years and a subadult about 15 years old, of indeterminate sex, with the child buried on top of the subadult, at the same time, in a pit surrounded by and filled with stones.

The boy has Harris lines on his bones, suggesting periods of arrested growth in his development, possibly indicating he was suffering from an infectious disease before his death. He was buried on his left side in a tightly contracted position, with his knees under his chin, facing towards the north, under about 65-95 cm of sediment, and his remains have been dated to approximately 7150 years ago.

The second skeleton has signs of an injury to the lower jaw, which caused a number of dental deformities, which possibly occurred when they were six or seven years old, as well as signs of an old injury to the left foot, which led to localised vascular disturbance. In addition to the injuries the skeleton had a hypertrophy of the supinator crest, which is an indication of regular practice with a throwing implement, such as a spear. The remains were buried in a half flexed half stretched position, the left arm stretched, the right one folded at right angle, and, like the younger child's, have been dated to 7150 years ago.

The final early stage grave appears to be a secondary grave for someone who was initially buried somewhere else. This contains a selection of limb bones, namely a right and left femur, right radius, and right fibula, all apparently from an 18-year-old male, 1.64 – 1.66 m tall. These were buried in a pit 60 cm deep, 75 cm long, and 25 cm wide, into which some Animal bones had also been deposited, although it is unclear if this association was deliberate. This individual appears to have been suffering from an unhealed ankle injury at the time of death, but was otherwise physically fit, with muscle attachments which suggest a powerful physique, and again regular practice with a spear or similar implement. These remains have been dated to 6870 years ago.

The wide range of dates obtained for these burials combined with the differences in burial style strongly suggest this was not a sign of a developing cemetery, but rather of a series of separate burials by different groups of people who moved through the area, and used the shelter temporarily, burying members of their groups who died while they were there.

 

 

Early and Late Holocene burial clusters from Shum Laka. Holl (2021).

The second group of burials are dated to between 3300 and 3000 years ago, and comprise fourteen sets of remains in nine separate burials, located at the eastern end of the excavated area. 

The first of these burials is a girl of about eight years old. The teeth of this girl suggest a series of severe health crises throughout her life beginning when she was about 6-9 months old, and continuing throughout her life. She was buried in a flexed position on her left side, facing to the north, about 7 m from the cave entrance and 25 cm deep. Her remains have been dated to about 3045 years ago.

The second of the younger phase burials is another young child, this time about four years old, and probably a girl. This individual seems to have been healthier than the first until the time of death, with some dental calculus, but no other pathologies. The body was laid on its back in a pit less than a meter from the previously described burial, and 4-5 m from the cave entrance. These remains have also been dated to about 3045 years ago.

The third of the younger phase burials contains two sets of remains, both those of adult women. This grave was placed 5 m from the rock shelter entrance, and was about 75-95 cm deep. They were placed on their sides, back-to-back, with the first woman facing to the west and the second to the east. Both sets of remains have been dated to 3300 years ago.

The first of these women was 20-30 years old and about 1.53-1.55 m tall at her time of death. She had several dental pathologies which suggest several episodes of illness or malnutrition in her childhood, with muscle attachments that suggest she was physically strong and regularly took part in repetitive physical activity.

The second woman is estimated to have been 30-50 years old at her time of death, and 1.43-1.48 m tall. Unlike the first woman, she appeared to be suffering from a number of health problems, including severe dental decay and Arthritis of the spine and lower arms, which appear to have related to her age and a lifestyle involving frequent hard labour. Despite this, she also appears to have been well muscled, and from the asymmetry of her muscle attachments, probably right handed.

 

The joint burial of two women from the younger burial phase at Shum Laka. Lipson et al. (2020).

The fourth burial of the new phase is located about 1.5 m to the north of the first, and contains 273 skeletal elements, derived from at least seven children, placed in a pit 1 m long, 60 cm wide, and 45 cm deep. This pit appears to contain a mixture of primary and secondary burials, with some of the remains showing signs of heating. The two primary internments are a boy of 5-7 years old showing signs of repeated environmental stresses in his life, and a stone arrowhead stuck in his left ilium, which appears to have been the cause of death, and another child of 10-16 years old. The remaining bones are from disarticulated skeletons, presumed to be secondary burials. These include three children aged 2-4 years, a 3-5 year old, and a 5-9 year old, most of which show pathologies that would have related to health problems in life.

This grave is confusing, and difficult to interpret, but Holl notes that there appear to have been two phases of burial within the same pit, with the two children identified as primary burials interned together, between 3180 and 3025 years ago, and the disarticulated and possibly cremated remains (which could not be dated) added later, possibly accidentaly uncovering the earlier grave in the process.

 

Burial Unit 7 (collective) showing disarticulated crania and one partially articulated post-cranial skeleton (20-30 cm below surface). Lipson et al. (2020).

The fifth of the new phase burials contains the remains of two robust adult males, aged 30-35 and 40-45 years. These remains had been cremated prior to burial, and was disarticulated and separated into three piles, the first containing cranial vault and tibia fragments, the second long bones and cranial vault fragments, and the third long bones and mandibulae fragments. These remains could not be dated, but appear to predate the third new phase burial, which overlies and partially disturbs this burial; this is a reversal of the situation in the fourth new phase burial, in which the deposition of cremated remains appears to have disturbed un-cremated remains which were buried earlier.

The final new phase burial is another set of cremated remains, this time of a single individual. In this case a high temperature appears to have been achieved during the cremation (probably about 800°C) resulting in very white and fragmentary remains, although parts of the skull, teeth, vertebrae, ribs, scapulae and clavicles, hands, sacrum, coccyx, and coxal bones, long bones, feet, and undetermined long bones could be identified, supporting the hypothesis that this was a single, intact, individual. These remains could not be dated, but again they appear to have pre-dated and been partially disturbed by, the third new-phase burial.

Although these burials represent a reasonably high number of individuals in a moderately short period of time (14 individuals in about 300 years), the differences in the ways in which they were buried, combined with the fact that some of the burials appeared to have accidentally disturbed older burials, suggests that this was still not a site being used specifically as a cemetery, but rather repeatedly chosen as a burial site by different groups of people moving through the area, and probably using the rock shelter as a temporary dwelling place.

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Coffea rizetiana: A new species of Coffee from Cameroon.

In the 1980s, the Institut de Reserche pour le Developpement carried out fieldwork in the rainforests of Cameroon and the Republic of Congo (Congo-Brazzaville), searching for new species and strains of Coffee. A large number of specimens were collected, several of which were considered to be representatives of new species, but none were formally described at the time, and the absence of fruiting or flowering specimens meant that none were included in a major review of the genus Cofea in 1998. However, subsequent additional collections have resulted in two of these species being formally described, Cofea charrieriana from southwest Cameroon in 2008 and Cofea anthonyi from Cameroon and the Republic of Congo in 2009.

 

In a paper published in the journal Adansonia on 21 December 2021, Piet Stoffelen of the Meise Botanic Garden, François Anthony of the Unité Mixte de Recherche's Interactions Plantes-Microorganismes-Environnement at the Institut de Reserche pour le Developpement, Steven Janssens, also of the Meise Botanic Garden, and Michel Noirot, also of the Unité Mixte de Recherche's Interactions Plantes-Microorganismes-Environnement at the Institut de Reserche pour le Developpement, describe a new species of Coffee from Mount Kupe in Cameroon, based upon samples collected in 1983 and cultivated at the Meise Botanic Garden, plus additional material collected in 2012, and placed in the Bassin Martin Coffee Collection.

The new species is named Coffea rizetiana, in honour of Georges Rizet of the Orsay University Paris XI, for his role in the 1980s expeditions. It is a small tree, reaching about six metres in height, with elliptical leaves about 6-9 cm long when fully grown, which produces large white flowers and distinctive black fruit, almost spherical and up to 2.3 cm long (this is distinctive among Coffee plants, which tend to have smaller fruit, which are red when ripe).

 

Coffea rizetiana, (A) habit; (B) node with flowers and petioles; (C) detail of flower; (D) fruit; (E) transection of the fruit with two seeds. Scale bars: (A) 3 cm; (B) 2 cm; (C)-(E) 1 cm. Antonio Fernandez in Stoffelen et al. (2021).

Coffea rizetiana has only been recorded growing in a single location, in the south of the Mouyouka-Kompina Forest, on the lower flanks of Mount Kupe, at an altitude of about 60 m. This area has since been cleared for agriculture, and the species is thought to be extinct in the wild, with surviving specimens growing in cultivation on Réunion Island and at the Meise Botanic Garden. It is likely that the distinctive fruit of Coffea rizetiana were consumed (and its seeds scattered by) different Animals than other species of Coffee growing in the area, though this is now impossible to judge.

 

Coffea rizetiana fruit showing its basis (right) and top (left) from the Coffea collection at Bassin Martin (Réunion, France). Stoffelen et al. (2021).

Mount Kupe appears to be somewhat of a hotspot for the genus Coffea, with at least six species growing on or close to its flanks. Coffea rizetiana formerly occupied the understory of the lowland forest on the mountain's lowest flanks. Coffea brevipes is only found on the drier north face of Mount Kupe, although this is otherwise a fairly environmentally tolerant species, found across a wide area of the lower Guinean and Congolian forests. Coffea montekupensis is found on the wet western and southern slopes of Mount Kupe at an elevation of 800 m to 1500 m; this species is found at similar altitudes at other sites in the Bakossi Mountains. Coffea bakossii is found growing at several locations between 700 and 900 m above sealevel; this species is also found elsewhere in the Bakossi Mountains, but is generally considered rare. Coffea liberica appears to grow all over the mountain, with no apparent favoured niche. This is unsurprising, as this is a widespread species found throughout the Guineo-Congolian lowland to submontane forests. Finally, the cultivated Coffea canephora (Robusta Coffee) is grown on the lowland forests surrounding the mountain; despite being grown in the area for about 50 years, this species does not appear to have naturalised to the area, and is not found growing away from Coffee plantations. At least another six species of Coffea are found growing in the forests of southwest Cameroon, leading Stoffelen et al. to recommend that the area should be targeted as a priority for conserving the wild biodiversity of the genus.

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Authorities in Cameroon seize eight African Grey Parrots from wildlife traffickers.

Officials from the Ministère des Forêts et de la Faune, acting on information provided by the Zoological Society of London, seized eight African Grey Parrots, Psittacus erithacus, from traffickers in the town of Djoum in the south of the country earlier this month. The Parrots are thought to have been on their way to the country's capital, Yaoundé, where they would probably have been sold on to pet illicit pet trade in Asia or Europe. According to the Zoological Society of London, Parrots are typically caught in glue-traps in Cameron, with one Bird being glued to the branch of a tree, and others being caught by the glue when they come to investigate. The Society regards this practice as extremely cruel to the highly intelligent Birds, as are the highly cramped conditions in which the Birds are transported, with many dying in transit. Trafficking in Parrots or other endangered wildlife can result in a prison sentence of up to three years in Cameroon, however the high value of the Birds combined with widespread poverty in the country means than many are still tempted to try.

 

Three of a group of eight African Grey Parrots, Psittacus erithacus, seized by the Cameroonian Ministère des Forêts et de la Faune in the town of Djoum earlier this month. Zoological Society of London.

African Grey Parrots are classified as Endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species. They are considered to be threatened across their entire range, both due to poaching and habitat loss, due to deforestation, with little organised protection for the species other than attempts to tackle the illegal pet trade, and a few local re-introduction programs in areas where they have been wiped out. The Parrots were formerly found from Angola and Tanzania north to Kenya and the forests of West and Central Africa, but are now thought to be locally extinct in Togo and Benin, and threatened across the remainder of their range. It is estimated that about 21% of the wild population is taken by hunters for the pet trade each year, with Cameroon losing around 100 000 Birds per year.

 

The current distribution of the African Grey Parrot, Psittacus erithacus. ICUN/Red List.

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Louisea nkongsamba & Louisea yabassi: Two new species of freshwater Crabs from Cameroon.

Crabs are Decapod Crustaceans related to Shrimps, Crayfish and Lobsters. Most Crabs occupy marine environments; however Freshwater and Land Crabs are widespread in the tropics. Members of the Family Potamonautidae are found across Africa, as well as Madagascar, the Seychelles, Zanzibar, Mafia, and Pemba islands in the Indian Ocean, and Bioko, São Tomé, Príncipe, and Sherbro islands in the Atlantic. The genus Louisea is known only from Cameroon, with two described species, Louisea edeaensis from the Lake Ossa wetland complex, and Louisea balssi from Kumba and Mt. Manengouba.

In a paper published in the journal ZooKeys on 17 Ocrober 2019, Pierre Mvogo Ndongo of the Department of Management of Aquatic Ecosystems at the University of Douala at Yabassi, the Museum für Naturkunde at the Leibniz-Institut für Evolutions und Biodiversitätsforschung, and the the Department of Biology at Northern Michigan University, Thomas von Rintelen, also of the Museum für Naturkunde at the Leibniz-Institut für Evolutions und Biodiversitätsforschung, and Neil Cumberlidge, also of the Department of Biology at Northern Michigan University, describe two new species of Louisea, both from Cameroon.

The first new species is named Louisea yabassi, in reference to the Yabassi Coastal Rain Forest where it was discovered. The species is described from two specimens, an adult male 18.11 mm wide and 12.78 mm long, and a subadult male 13.82 mm wide and 10.61 mm long. Both were collected in 1909 by Fritz Wilhelm Riggenbach, and were found in the collection of the Museum für Naturkunde. Louisea yabassi has a smooth, flat and nearly oval carapace, and unequal claws, with the right being larger than the left.

Largest adult male of Louisea yabassi. from Yabassi  (missing left p2–p5, and right cheliped and p2, p3). Scale bar is 8.42 mm. Mvogo Ndongo et al. (2019).

The second new species is named Louisea nkongsamba, in reference to Nkongsamba, the closest town to the Nlonako Wildlife Reserve, where the species was discovered. This species is described from two adult male specimens collected by Pierre Mvogo Ndongo, the larger of these being 20 mm wide and 14.85 mm long, the smaller 18.38 mm wide and 13.32 mm wide. Louisea nkongsamba has a smooth oval carapace, a stout but different-sized claws and slender walking legs. It is dark green or brown in life.

Second largest adult male of Louisea nkongsamba from Mt. Nlonako. Scale bar is 11.63 mm. Mvogo Ndongo et al. (2019).

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