Leonardoxa africana explained

Leonardoxa africana is a tropical tree endemic to west-central Africa and southeastern Nigeria. It is divided into four sub-species, of which three are myrmecophytes.[1]

Subspecies

Description

The species grows to a height of between 4-14m tall, its diameter can reach a width of 45 cm but commonly less than 40 cm. Leaves have a pinnately compound arrangement, with 2-4 pairs of leaflets per pinnae but commonly 3 pairs per pinnae; leaflets have a falcate to elliptic shape.[2] Inflorescence is raceme type, 40-60 flowered, position is commonly cauliflorous or ramiflorous, borne on main trunks or twigs but occasionally axillary on young twigs. Pedicel is 2-4 mm long, Calyx is green or red, sepals 0.5-0.8 cm long, petals are commonly violet, pink, mauve, or purple colored.

Habitat

An under-storey tree, it grows near seasonally inundated regions and on dense sands in freshwater rainforest regions of Central Africa.[3]

Ecology

The ant species Petalomyrmex phylax, Aphomomyrmex afer, and Cataulacus mckeyi occupy swollen internodes or domatia of most subspecies of Leonardoxa africana and they feed on the nectaries usually at the base of leaflets and close to the midrib. Petalomyrmex phylax occupy young internodes while Cataulacus mckeyi and Aphomomyrmex afer patrol the basal parts of mature leaves.

Chemistry

Methyl salicylate and hexanones have been identified as two compounds in young and mature leaves of the species.[4]

Notes and References

  1. 2000. Leonardoxa africana (Leguminosae: Caesalpinioideae): a complex of mostly allopatric subspecies. Adansonia. en. 22. 1. 71–109.
  2. Mckey. Doyle. 1984. Interaction of the Ant-Plant Leonardoxa africana (Caesalpiniaceae) With Its Obligate Inhabitants in a Rainforest in Cameroon. Biotropica. 16. 2. 81–99. 10.2307/2387840. 2387840.
  3. Gaume. Laurence. McKey. Doyle. Anstett. Marie-Charlotte. 1997-10-01. Benefits conferred by "timid" ants: active anti-herbivore protection of the rainforest tree Leonardoxa africana by the minute ant Petalomyrmex phylax. Oecologia. 112. 2. 209–216. 10.1007/s004420050302. 28307572. 12539426. 0029-8549.
  4. Brouat. Carine. McKey. Doyle. Bessière. Jean-Marie. Pascal. Laurence. Hossaert-McKey. Martine. 2000. Leaf volatile compounds and the distribution of ant patrollingin an ant-plant protection mutualism: Preliminary results onLeonardoxa (Fabaceae: Caesalpinioideae) andPetalomyrmex(Formicidae: Formicinae). Acta Oecologica. en. 21. 6. 349–357. 10.1016/S1146-609X(00)01091-2.