The genus Sohnreyia is represented by a single species, S. excelsa, which was
described by Krause (1914) from specimens gathered by Ule. Sohnreym like
Diomma, is one of those dicotyledons with a palm-like habit. Krause describes
this plant as an erect, palm-like tree with a slender unbranched trunk bearing
very large pinnate leaves crowded at the apex. Also, like Diomma, Sohnreyia
is a species which blooms and fruits but once at the termination of its existence
(Krause 1921; Ducke 1930).
Krause (1914) notes that the large, pinnately compound leaves of Sohnreyia
are glandular-punctate. Flowers are white, regular, polygamous, 5-merous, and
disposed in loose, many-flowered panicles. The free stamens are inserted at the
base of a gynophore opposite the sepals. In the female and bisexual flowers,
stamens are smaller than in the male flowers. The filaments are provided with
a wing-like, bifid appendage in the lower part. The 2-locular ovary is inserted
on a thick, subcylindrical gynophore. Ovaries are small, rudimentary, and
estigmatose in male flowers, but in female and bisexual flowers the ovaries are
larger, somewhat laterally compressed, and in females bear a short style terminated
by a fairly large, bilobed, discoid stigma. Ovules are pendulous, anatropons,
and solitary in each locule of the ovary. Krause did not see fully
developed fruits. However, in 1922, Ducke described the fruits of Sohnreyia
as resembling the samaras of certain Combretacrae, e.g., Terminalia argentea.
However, he noted that the fruits of Sohnreyia were 2-secded, dry, and with 2
membranous confluent wings which are conspicuously reticulate. According to
Ducke and Black (1953), Sohnreyia e.reeha is scattered in Brazil on uplands from Manaus to the lower part of the Trombetas River north of the Amazon
River, and south of the Amazon River from Juruti Velho and Maues to the
northern part of the Mato Grosso and the Territory of Guapore.
Krause (1914) placed Sohnreyia in the Rutaccac, in an isolated position,
mentioning- that it could be related to Dictyoloma, but lacking mature fruits no
definite association could be made. Bngler (1931) agreed with Krause regarding
the definitely rutaceous nature of Sohnreyia. and erected a special monotypic
subtribe Sohnrcyiinac under the tribe Toddalieae of the subfamily ToddaJioidcae
to contain this genus.