Hamann, Ole

Wium-Andersen, Søren

English

Aquatic Commons

This is true for instance of the highly important evergreen Scalesia forests. The genus Scalesia 
(Compositae) is endemic to the Galapagos. Some species grow into trees, the most common of which is S. 
pendunculata. It occurs on Santa Cruz, San Cristobal, Santiago and F10reana and it is in these last two 
islands that it is under the most immediate threat from introduced animals. On Santiago the situation is so 
grave that it has been necessary to protect a few mature individuals with goat-proof fences. On F10reana 
there are still some small popUlations but these are under pressure from the aggressive Psidium guajava and 
Lantana camara (see Noticias 43). Fortunately on Santa Cruz large stable forests remain. 
The GNPS and the CDRS are currently engaged on assessments both of the Scalesia situation and of the 
more aggressive introduced species. It seems inevitable that if action cannot be taken some Galapagos 
species will become extinct. For instance on F10reana there are, or were, several species never found 
anywhere else: Psycho tria angustata. only collected twice; Lippia salicifolia. not found for many years; 
Darwiniothamnus tenuifolius. now reduced to very small populations. Henning Adsersen (pers. com.) 
estimates that perhaps 100 of the 500 native Galapagos species are vulnerable if not actually endangered. 
Their preservation depends on the availability of adequate human and financial resources. 
SCALESIA GORDILLOI 
A NEW GALAPAGOS PLANT SPECIES 
by 
Ole Hamann (1) and Seren Wium-Andersen (2) 
(1) Univ. of Copenhagen. Inst. of Systematic Botany. 140 Gothersgade. DK -1123. Copenhagen K. Denmark 
(2) Univ. of Copenhagen. Freshwater Biological Laboratory. 
51 Helsingersgade. DK - 3400 Hillered. Denmark 
During a visit to the Galapagos in 1982 for the purpose of studying the mangrove communities we were 
escorted round San Cristobal by Senor Jacinto Gordillo, a local teacher and naturalist, who has long been 
the resident representative of the Charles Darwin Research Station in that island. He drew our attention to 
a species of Scalesia near Puerto Baquerizo, the administrative capital of the archipelago, which he 
considered to be a hitherto undescribed species. Subsequent study has shown that his acute powers of 
observation had led him to a correct diagnosis and we therefore decided to name the new species in his 
honour, Scalesia gordi/loi. 
Jacinto Gordillo, a resident of San Cristobal, 
who for many years has represented the CDRS in that island. 
13 
Noticias de Galapagos, vol. 44 1986
The genus Scalesia is endemic to the Galapagos and, with the inclusion of S. gordilloi, now contains 15 
species (21 taxa). The Scalesias are erect, usually single-stemmed shrubs or small trees from 0.3 to 15 
metres in height. Their morphological diversity is parallelled by their diversity of habitat (Eliasson 1974, 
Hamann 1981) ranging from the humid highlands to the restricted area of loose lava rocks in the arid 
coastal zone, to which the new species is confined. Few Galapagos islands are without representatives of 
the genus ana a number of islands have more than one. San Cristobal now has 4 but none of these overlaps 
with S. gordilloi. 
S. gordilloi is easily recognised by the combination of entire leaves with minute glands, few-flowered, 
relatively small heads and small paleae (Fig. 1). It grows to a height of about 1.5 metres. 
Scalesia gordi/loi. type specimen. 
A: Flowering shoot. B: Fully developed leaf. C: Upper surface of leaf. D: Under surface of leaf. 
E: Head. F: Phyllaries. G: Paleae. 
H: Flower and fruits, the fruits with variously developed pappus, either as pointed sets or as blunt callosities. 
REFERENCES 
Eliasson, U. (1974) Studies in Galapagos Plants. XIV. The Genus Scalesia Arn. - Opera Botanica 36. 
Hamann, O. (1981) Plant Communities of the Galapagos Islands. - Dansk Bot Arkiv 34(2). 
14 
Noticias de Galapagos, vol. 44 1986


Scalesia gordilloi a new Galapagos plant species

http://aquaticcommons.org/5782/1/NG_44_1986_Hamann%26Wium-Andersen_Scalesia_gordilloi.pdf

Scalesia gordilloi a new Galapagos plant species

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