Congo Research

Adolfus sp.

Adolfus vaureselli

Congo Basin

• Bowl-shaped depression surrounding congo river

• Congo river- 2nd longest

• Region spans 6 countries

• 3 million km2 of tropical forest

• 6 major ecoregions

Poorly Explored Biodiversity

• Okapi 1901

• Bonobo 1928- south of the congo river

• Congo peacock 1936:

• 125000 western lowland gorillas in 2008

Montane speciation vs. refuge hypotheses

• Kingdon 1989: Congo Basin is an evolutionary whirpool

• Both advocate allopatric diversification by climate induced range expansion and contraction

• Lowland rainforest refugia vs. montane forest focus

• Two olivaceus clades distinguished by differences in RAG1 codons and morphology.

Herp Endemicity in Congo Basin

• Amietophrynus, Barej 2011

• Hyperolius Schick 2010

• Osteolaemus Eaton 2009

• Lepidothyris 2009

Three known congo basin toads

• Sclerophrys camerunesis

• Schlerophrys gracilipes

• Schlero Latifrons

Phylogenetic tree

• schlerophrys monophyletic

• Non-forest species at base of scherophrys clade

• Thought: 3 species, but there was 17 specialist toads

A camerunensis

• Can cross ecoregions, rivers, it can move around within a very short amount of time.

• Found everywhere in the congo.

Cryptic toad diversity concentrated in fork between tshuapa and salonga rivers

Most toads don’t have the ability to swim rivers

Tree suggested a rapid radiation in the congo basin

congo basin toads node: ca. 7-14 mya

Species hide in cold weather, they get in “refugees” allopatric situation. They only stay in their area bc otherwise they can die.

Conclusions

• Refugee hypothesis supported by data: congo basin is a center of speciation

• Forest refugia and river barrier formation in the late Miocene likely processes to explain speciation pattern

• Multiple cryptic taxa present, including many new species

• Multiple areas of endemism:

  • Area when you have a species that occur there and nowhere else.

• People thought there was 4 areas of endemism in Africa, WRONG!

  • There are MANY! Areas of endemism for toads in Africa

• Even with snakes, you find very similar patterns.

Toads lack typical rugose, warty skin commonly associated with the members of the family buforidae