Isopod: Working as Architect, Builder
ESF Top 10 New Species of 2016
From the Author...
The terrestrial crustaceans in the suborder Oniscidea found in Brazilian caves include many new species that have only recently begun to be described. The collaboration between researchers is important in this type of work because the strong suits of the individuals complement each other. Thus, our biospeleologist Rodrigo painstakingly searches the caves and brings to light species from the bowels of the earth so that taxonomists like me (Leila) can study and describe them. The new knowledge enables us to protect this rare fauna. André, our specialist in another crustacean group, Amphipoda, came aboard our new-species-describing adventure, providing us with his illustrating skills and thinking. He is also good at organizing papers according to official rules so that they are ready for publication.
Iuiuniscus iuiuensis, whose name was based on the location where we found it, is an exclusively subterranean species, and therefore eyeless and nonpigmented. When I examined it for the first time, one morphological trait struck me: the sides of the body were jagged into big spikes, like in no other member of this family (Styloniscidae)!
I was even more surprised after seeing photos of the little “homes” which this species builds using sediment from the cave. This was new for the entire suborder! The only similar case involved the digging of shelters in the ground outside caves. These “homes” offer protection against predators during times of vulnerability, such as molting, when the exoskeleton is replaced, and hatching, when the young emerge from the eggs kept in the marsupium, an egg pouch in the ventral part of the mother’s body. In addition, this species, like few Oniscidea, is amphibious and spends part of its life cycle in water. The spikes probably repel potentially predatory fish with which they share the ponds.
This wonderful species deserved a new genus and a new subfamily!
— Leila A. Souza
About the Isopod
Name: Iuiuniscus iuiuensis
Size: 9.2 mm (about a third of an inch)
Etymology: Named for the type locality, Iuiú
Type locality: Brazil, Bahia, Iuiú, in Lapa do Baixão cave
Holotype: Universidade Federal da Bahia, Instituto de Biologia, Salvador, Bahia, Brazil
More information: Leila A. Souza, Rodrigo L. Ferreira, and André R. Senna. 2015. Amphibious shelter-builder Oniscidea species from the New World with description of a new subfamily, a new genus, and a new species from Brazilian cave (Isopoda, Synocheta, Styloniscidae). PLOS One 10 (5): e0115021. DOI: 10.1371/journal.pone.0115021