Another option could be using the A-criterion, and the decline of its habitat if the decline can be inferred. /Anders
Cantharellus afrocibarius is an edible changerelle, only known from woodland in southern Democratic Republic of Congo, and northern Zambia. It is rare in the southern part of its range, but can be fairly common further north. However, ongoing threats to its habitat mean that the species is thought to be in decline. The population size is estimated to fall in the range 2,500-9,999 mature individuals, all of which could be said to be in one subpopulation. Therefore, C. afrocibarius is assessed as Vulnerable under criterion C2a(ii).
This species is only known from Zambia and the Democratic Republic of Congo. The type was collected near Chibuli, Copperbelt Province, Zambia (Buyck et al. 2013), while further collections, and reports of consumption, have come from Haut Katanga Province, Democratic Republic of Congo (De Kesle et al. 2016, 2017).
The species appears to be rare in the southern part of its range, however, it appears to be “fairly common” further north (see Buyck et al. 2013, De Kesel et al. 2016). Using Dahlberg and Mueller (2011), it may be appropriate to think that in the south of its range each functional individual should be treated as two mature individuals, whereas further north, each should be treated as ten. Also taking into account relative abundance of the species across its distribution, it could be that the species only occurs at a handful more sites in the south of its range (c.25 sites); whereas further north there could be several hundred potential sites for the species (c.250 sites). Overall, based on these figures, the population size would be 2,550 mature individuals. This may still represent an underestimate, but there would require over 1,000 sites in the northern part of the species’ range in order to exceed the thresholds for Vulnerable under criterion C (given the scarcity of the species in the southern part of its range, it is suspected that even if each functional individual was treated as ten mature individuals, this would not have a significant impact on the overall population size).
The species is also thought to be in decline, as even though it may be associated with a range of different woodlands, and species types, ongoing threats to its habitat will be leading to declines. Rates of forest loss are quite difficult to calculate because of its potential association with a range of different woodlands. Using Global Forest Watch data (2022) between 2010 and 2021 forest cover at 30% canopy cover declined by 726 kha within its potential range, which is roughly equivalent to a 12.1% loss of forest cover (although it is uncertain what % of this was old forest cover). As an ectomycorrhizal species it has a three generation period of 50 years (see Dahlberg and Mueller 2011), and assuming an exponential decline over this time would give an overall decline of 44.5%. Translating this to a population decline is particularly difficult for this species as it appears to have a noticeable variation in its population density across its range, and it is difficult to tell to what degree this loss of forest cover is actually loss of suitable forest habitat. At least, though, the population may be precautionarily suspected to be declining at a fairly rapid rate - potentially approaching the thresholds for listing as threatened under criterion A (20-29%).
Population Trend: Decreasing
The type was collected in Brachystegia woodland, while further collections have occurred in various types of woodland, in particular miombo containing Brachystegia and Julbernardia (De Kesel et al. 2016). It is generally found in older woodland (De Kesel et al. 2016).
Miombo woodland faces a range of threats, which would likely impact this species because it favours older woodland. The most pressing will be the destruction of this habitat type through logging, in addition to clearance for agriculture (see Jew et al. 2016).
Where possible, actions should be taken to protect suitable habitat for this species, including engagement with local stakeholders.
Further research is needed to get a clearer estimate of the population size and trend, as well as identifying how widespread the species could be.
This species is reported to be edible (Degreef et al. 2016, De Kesel et al. 2017).