A large sample of Siphonophoridae from Brazil was studied; two morphological groups
could be distinguished. Here species considered to be from the genus
Columbianum
Verhoeff, 1941
are examined in detail. The genus is known from Central and South America (guatemala, Panama,
Honduras, guiana, Colombia, Peru and Brazil) and is characterised by a clear demarcation between
head and rostrum in combination with long antennae, clearly surpassing the tip of the rostrum. A list of
previously described species considered to belong to the genus is given; three new species are described:
C. major
sp. nov. has a large body size and a small head,
C. nahvalr
sp. nov. has a particularly pronounced
domed head and a more castellated appearance to the body,
C. adisi
sp. nov. has a small body size and
a very characteristic hind margin to the pleurites. Variation in the state of preservation of specimens
hinders a diagnosis, but the examination of the accessory claw and details of the metazonital limbus
and pleurite edges are helpful. Unusually for Diplopoda, the male gonopods are not very useful for
identification. Ecological comments are given for each new species, one of which,
C. adisi
sp. nov., is
from the seasonally flooded forest and appears to avoid inundation by climbing trees.