Ministry for natural resources and the environment directorate general for environment




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2.8 Biodiversity of land fauna


Vertebrate land animals in the country are fairly well known. However, there is a manifest lack of more profound studies of invertebrates or land/aquatic microorganisms such as hydrozoa, spongiaria, polychets, nematodes and more.

2.8.1 Land mammals
According to the data published by the National Environmental Plan for Sustainable Development (PNAAD), among land mammals we may count: Monkeys (Cercophitecus mona), wild pigs (Sus domesticus), six species of bats, Myonycteris branchycephala, Hippodsiderus commersoni, Miniopterus minor and Rousettus aegyptiacus, along with mainland species like Eidolon helvun and Hipposideros ruber. Besides bats, there are two kinds of shrews, namely Crocidura thomensis and Crocidura poensis, as well as mice, Rattus rattus and Rattus norvegicus1.
This table lists the land mammal species enjoying protection status in S. Tomé and Príncipe.
2.8.2 Birds
Sylvan avian fauna (see table 9 below) is comprised of 63 species, of which 25 are endemic, including species typical of rainforests, namely, Lanius newtoni, Bostrychia bocagei, Amaurocichla bocagii and Neospiza concolor. Other prominent species are Columba malherbii, Columba thomensis, Treron australis virescens, Streptopelia senegalensis, Aplopelia larvata simplex or principalis.
Along coastal areas, the fauna is made up mostly of birds inhabiting small islets and coastal areas away from human settlements. Main species nesting in colonies are Phaeton lepturus (Coconzucu), Sula leucogaster, Sula dactylatra, Anous stólidus, Anous minutus, Sterna fuscata, Sterna anaethetus and Oceanodroma castro (band-rumped storm-petrel). In the savannas of northern S. Tomé, there is a distinct group of birds comprised of quails (Coturnix delegorguei) and the African crake (Crecopsis egregia).

Table 9 shows the avian species protected in the archipelago. They are distributed throughout 13 different families. The order Passeriformes includes the largest number of species.


2.8.3 Batrachians or amphybians

Santomean batrachian fauna is constituted by 3 families, 5 genera, and 7 species. 6 have been reported in São Tomé, 2 in Príncipe and 2 on the Ilhéu das Rolas. Distribution is as follows. A species common to all three islands, Rhynobatrachus dispar,one species in São Tomé and the Ilhéu das Rolas, Schistometopum thomense, 4 endemic to São Tomé, Schistometopum ephele, Nesionixalus molleri, Nesionixalus thomensis and Rhynobatrachus dispar and one on Príncipe island, Leptopelis palmatus.

On São Tomé there are the following endemic species: Moller’s gulf frog, Nesionixalus molleri and the Nesionixalus thomensis, the São Tomé tree frog; the Ptychadena newtoni frog and the caecilians, Schistometopum thomense and Schistometopum ephele.

On Príncipe island there are the two frogs, Leptopelis palmatus and Phrynobatrachus dispar.

There are also apods like the bôbô snake which, although not strictly tied to aquatic environments, can be found in humid environments, building galleries after the manner of worms.

2.8.4 Land reptiles
In terms of phylogenetics, reptiles descend from amphibians. They conquered the subaerial environment after they solved reproduction problems in the Paleozoic. Their presence in the country’s fauna is of great ecological worth. This class of vertebrates is represented by 16 species on the islands of São Tomé and Príncipe.2

On the island of São Tomé the following species can be found: Geckos (Hemidactylus greeffii), Panaspsis africana lizards, the beaked snake Rhynotyphlops newtoni and the black cobra, Naja melanoleuca.

On the island of Príncipe the following species can be found: the legless lizard Feyinia polylepis and the snake Typlops elegans.

The gecko Lygodactylus thomensis is endemic to the islands of São Tomé and Príncipe.

The order Chelonia is represented by: the swamp turtle Pelusio castaneus and the forest turtle Pelusio gabonensis. These turtles are increasingly rare in our ecosystems; their numbers tend to diminish. There is no accurate population count or information on status and distribution of either species, for which reason it is necessary to undertake studies on the taxonomy, reproductive biology and ecology of both species (ENPAB-Inland Water Ecosystems, 2002).
2.8.5 Sweet-water fish
Small fish are predominant in sweet waters, such as Eleotris vittata and Pomadasys jubelini, Plynemidae.
2.8.6 Land and sweet water mollusks

Likewise, several species of mollusks are present, such as Neritina afra, Neritina manoeli, Bulinus forskalii and Schistosoma intercalum, which is responsible for the schistosomiasis recently detected on São Tomé and Príncipe (Brown, 1991, 1994).



2.8.7 Insects

Entomological fauna on the archipelago includes about 89 species of butterfly. São Tomé presents 47 species and Príncipe 42; rate of endemism is, respectively, 38% and 21%.

There are endangered endemic species of insects such as Lepidoptera, Graphium leonidas thomasius e oelides bocagii (ENPAB-Forest Ecosystems, 2002). Other species of butterflies (not endangered) are Charaches, Dixeia piscicollis, Neptis eltringhami. As stated above, these species are under constant pressure from fires, both agricultural-related and spontaneous.

Myriapods are represented by Globanus integer and Blobunus marginescaber, which are protected species.

The data included in the last biodiversity report do not mention lepidoptera or choleoptera. Bees of the genus Apis are honey bees and very important to impollination and fertilization of flowering plants, therefore contributing to the preservation of forested areas. The coevolutionary plant-insect relationship may be used in apiculture. Interventions in this domain must include the preservation of entomological fauna. This presupposes control, inventory and species density. The final result of the process is conservation of the environment.

In the agrarian sector, insects are pests to several cultures, such as:



  • Flies, aphids, rust mites, ticks, damaging to tomato plants (Licopersicum sppl.);

  • The green scale (Coccus viridis) and the Leaf Miner (Phyllocnistis citrella), which affect citrus fruits (Citrus sppl.);

  • The crotcha, the weevil and the Noctuidae larvae threaten profitable cultivation of corn;

  • Aphids causing banana tree (Musa sppl.) spot disease;

  • Selenotrips rubrocinthus causing low production of cocoa (Theobroma cacao);

  • Fruit flies, named Ceratitis coffeae and the coffee-tree aphid, Antestiopis lenea ticollis;

  • Moth and red-necked peanutworm, affecting peanut plants (Arapis hypogea);

  • Mites, aphids and silverleaf whitefly, affecting production of tapioca (Manihot esculenta). This culture is also affected by the diseases stemming from the action of Bemisia tabaci, the sweetpotato whitefly.


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