Description

Ecology All the individuals were collected from an inundation forest, Igapó. Almost all the specimens were collected from TM 50, TM 51 or TM 52, which were traps on trees catching downward movement. A few were from TM 47 (tree traps catching upward movement and a few also from standing crop studies. Table 2 shows the numbers of individuals found in different months (most were collected in 1976, but a small number from 1977 are also included). This forest is inundated from March / April until August / September (see Wolf & Adis 1992 for more information). It can be seen that most individuals were found during the end of the time when the forest was inundated. The majority of these specimens were captured walking down trees. The single male in May, one female in February and one female in November were found walking up trees. In addition, one male in June and one in July were recorded as part of standing crop surveys, together with one female in February and 7 in June. This suggests that the bulk of the movement down trees takes place in July – September, during the inundation period although towards the end. Presumably this species spends the beginning of the inundation period in the trees, but where it lives the rest of the year is not known. It is tempting to think that the long setae and the paddle-shaped claw have something to do with the habitat of this species in the forest, which is seasonally inundated. However, the claw shape, although perhaps most pronounced in the males of this species, is also found in S. hebetunguis (details of the habitat of this species are unknown) and perhaps in a less pronounced way in S. tuberculata sp. nov. (see below). The final column in Table 2 indicates the number and proportion of ‘ long-haired’ males in the samples. For this purpose, a ‘ long-haired’ male is considered to be one with setae equal to or more than 0.08 mm long. From this it is apparent that ‘ long-haired’ males can be found at almost any time of the year. Although more ‘ long-haired’ individuals were found towards the end of the inundated period, this is also when more individuals were collected in general. The considerable size range of the males in terms of number of body rings suggests that individuals continue moulting after attaining maturity. However, it cannot be determined from the present collection whether males moult between long and short setal forms, the long setae develop over a series of moults, or they moult into a long (or short) setal form and then continue with this morphology. See Table 1 for comments concerning differences between this species and others from Brazil.

Common Names

Taxonomic Hierarchy

Kingdom: Animalia

Phylum: Arthropoda

Class: Diplopoda

Order: Siphonophorida

Family: Siphonophoridae

Genus: Siphonophora

Species: Siphonophora setaepromissa Read & Enghoff, 2019