Subterranean Fishes of the World

4581

1981

Giornale Botanico Italiano

372-373

115

The research carried out so far on Somalia's underground waters has provided a biogeographical picture of the distribution of the fauna of the fauna that has been found to be different from one environment to another (L., PARDI, 1976 - Zool monitor. Ital. (NS) , 7: 195-269). Little is known about the flora of these microenvironments: a survey dates back to 1929 and was carried out, only at the level of the Diatoms by CHIOVENDA (1929 - Somali Flora). The results of this work refer to the study of the algal flora present in two distinct environments of Southern Somalia (Baidoa and Bud-Bud) in whose waters two different species of phreatobium fish were found: Uegitglanis zammaranoi (in the Baidoa wells) and Phreatichtys andruzzii (in the Bud-Bud wells) (L. PARDI, 1976 - Zool monitor. ital. (N. S), 7: 195-269). The survey was conducted in February and March 1978 on samples of both materials attached to the well wall and on water and bottom sediment samples. The flora observed was very poor in shape and is represented in the complex by 27 species including 7 Blue Algae, 18 Diatoms, 1 Chlorophycea and 1 Euglenoficea. The Cia-noficee, in both environments, are mostly thickened at the edges of the wells, attached to rigid substrates. They are represented in particular by a rich flora in Lyngbia martensiana associated with Lyngbya limnetica, L. nordgardhti and L. versicolor. The same are found, fragmented, in the water and background samples together with a minimal representation of Spirulina platensis, S. meneghiniana and Microcvstis aeruginosa (the latter in the Bud-Bud samples only). The Diatoms, on the other hand, are differently represented in the two environments both in quantity and in number of species. They are very scarce in the wells of Baidoa (6 species: Navicula bacillaris, N. mutica, Amphora somalica, Nitzschia amphibia, N. obtusa) and frequent instead in those of Bud-Bud (12 Species: Cyclotella comta, Fragilaria virescens, Ceratoneis arcus, Synedra ulna, Achnanthes brevipes v. parvula, Rhoicosphenia curvata, Diploneis ovalis, Anomoeoneis sphaerophora, Navicula bacillaris, N. mutica, Amphora somalica, Cymbella turgida, Gomphonema an-gustatum, G. parvulum, Nitzschia amphibia, N. epiphytica) where some of them, Fragilaria vens . parvula, Diploneis ovalis and Nitzschia epiphytica reach a considerable abundance in both the water samples and those taken from the well wall. The results obtained do not differ much from what the CHIOVENDA had already observed in 1929 and the species found are among those already mentioned for East Africa, in particular for Nyassaland, by SCHMIDLE (1902 - Engler's Bot. Jahrb., 32 : 56-87) and by WOMAN (1904 - Engler's Bot. Jahrb., 34: 9-201). It is worth noting the excessive wealth of species and individuals in these unique environments that, due to their lighting conditions, temperature (25-29 "C) and water stagnation would hypothesize a greater abundance of microflora.

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