D.brevifolia Pursh, D.capillaris Poir., and D.intermedia Hayne have a very similar distribution pattern in the New World, occurring in both North, Central, and South America. D.brevifolia is known from the southeastern USA, Mexico, Belize, Cuba, Brazil, Uruguay (Schlauer, 1987), Argentina, and Paraguay (Dawson, 1938). D.capillaris has been found in the southeastern USA, Mexico, Cuba, Colombia, French Guiana, Guyana, Venezuela, Brazil (Schlauer, 1987). Last of all D.intermedia is known to occur in southeastern Canada, eastern USA, Cuba, Trinidad, Guyana, Surinam, Venezuela, and Brazil (Schlauer, 1987; Silva, 1994), not to mention Europe too. I have even seen a specimen supposedly from western Africa.

So what do these three species have in common, other than belonging in subgen.Drosera (Schlauer, 1987) and having a chromosome number of 2n=20 (Wood, 1955)? Judging from the large morphological diversity, one could suggest that all three species originated in the southeastern USA (or maybe northern S.America in the case of D.capillaris). But most important of all, these three species have a very similar disjunct distribution along the eastern Americas. Strangely, all three skip the Amazon and central Brazil, reappearing in hot and humid sandy coastal habitats of Brazil known as ‘restingas’, where many Utricularia spp. are also common.

According to herbarium specimens I’ve seen, D.intermedia is known from a few locations in eastern Brazil. In Bahia it has been collected at a town called Camaçari, near the capital city, Salvador, as well as in two towns called Caravelas and Belmonte on the southern tip of the state, near the border with the state of Espírito Santo, where it is probably also found. Further south, it has been collected near three towns on the northern coast of Rio de Janeiro: Campos, Macaé, and Cabo Frio. One of these, Sitio de Paulistas near Macaé is the type location for D.capillaris Poir. var.brasiliensis Diels, which is a synonym of D.intermedia (the plants were incorrectly identified by Diels).

I have searched for D.intermedia at Cabo Frio, unsuccessfully. The herbarium collections are several decades old and since then numerous beach house developments have possibly extinguished this species in that region. Yet I did see wild D.intermedia at the Gran Sabana in southern Venezuela, where it supposedly extends a bit into northern Brazil along the Guyana Highlands. In Eastern Brazil this species is recorded to be a deep wine-red in color and have white flowers. It probably grows as a perennial, without any dormancy. The loose rosettes have semi-erect leaves up to around 3.5cm in length and with inflorescences reaching nearly 15cm in height.

D.capillaris occurs further south along the Brazilian coast than D.intermedia, without any overlap, from the state of São Paulo south through Paraná, Santa Catarina, to Rio Grande do Sul. It very likely also occurs in Uruguay. This region has short cool winters, not enough for D.capillaris to go dormant or grow as an annual. It simply slows down a bit during the colder months. The flowers are light pink in color, on scapes usually less than 10cm in height, and the flat leaf rosettes are a reddish-green in color, around 2-4cm in diameter.

I’ve studied D.capillaris at two locations I São Paulo, where it has successfully colonized areas deforested for beach developments, leaving the sandy soil beneath exposed to sunlight. I cultivated specimens from Torres, in R.Grande do Sul, which were identical to the São Paulo plants. D.capillaris, like D.intermedia, is also found in northern Brazil on the Guyana Highlands.

D.brevifolia occurs sympatrically with D.capillaris in Paraná, S.Catarina, and R.Grande do Sul, but no records of hybrids exist. D.brevifolia, is known to extend south into Uruguay, and curiously, up from the coast into the southern highlands of Brazil and even further westward to northern Argentina and southern Paraguay. I have heard a few unconfirmed reports of D.brevifolia on the southern coast and highlands of S.Paulo, where it may very likely occur since it has been collected just over the border in Paraná. I have also seen live specimens of what appeared to be this species from highlands near Airuoca, which is quite far away, in southeastern Minas Gerais state.

I studied several natural locations of D.brevifolia on the eastern highlands of Paraná and have also cultivated specimens from Torres, R.Grande do Sul. Once again no significant variation was observed between specimens from different areas. The small flat leaf rosettes are green when shaded by grasses all the way to a deep-red when fully exposed to sunlight. Flowers of D.brevifolia are a light pink-lilac and appear mostly in the spring, between September and November. Inflorescences are usually less than 10cm long and the leaves usually less than 1.5cm in length. The rosettes often shrivel and die after flowering or during the dry winter, but new rosettes soon emerge from the dormant rootstock.

References:

1.) Dawson, G. 1938. Las especies del género Drosera de la flora Argentina. Rev. Arg. Agron. 5: 231-239.
2.) Diels, L. 1906. Droseraceae. In Engler, A. (ed.). Das Pflanzenreich 26 (IV, 112). Leipzig.
3.) Saint-Hilaire, A. 1824. Droseraceae. Histoire des plantes les plus remarquables du Brésil et du Paraguay 1: 253-271. Paris.
4.) Schlauer, J. 1987. Nomenclatural Synopsis of Carnivorous Phanerogamous Plants. Carnivorous Plant Newsletter 15: 59-117.
5.) Silva, T.R.S & A.M.Giulietti. 1997. Levantamento das Droseraceae do Brasil. Bol. Bot. Univ. São Paulo 16: 75-105.23.
6.) Wood, C.E. 1955. Evidence for the hybrid origin of Drosera anglica. Rhodora, 57, 676: 105-130.