Ontogenia, polietismo fisiológico e plasticidade de ninhos em Nasutitermes ephratae (Homlgren, 1910) (Termitidae : Nasutitermitinae)

Abstract

Nasutitermes ephratae, an arboreal wood-feeder higher termite from Neotropical region was analyzed regarding i) ontogeny pathway for caste development; ii) structure of gut bacterial community among six different instars of neuter lineage; iii) and policalism and nesting plasticity behaviors. Seven morphometric measurements were taken from several distinct instars of N. ephratae and analyzed by principal component analyses (PCA). The development system was similar to previously describe Nasutitermes genus, with a first instar larvae molt into neuter or reproductive lineages; reproductive line comprising five nymphal steps plus alates; a high polymorphic neuter lineage, within 5 worker instars and monomorphic soldier and presoldier. The microbial intestinal community was checked by high-throughput sequencing of 16S rRNA and remarkable differences were observed between young and old worker instars. A transition from wood-cellulolytic bacteria (Spirochaetes, Fibrobacteres) to humus-degrading bacteria (Bacteriodetes, Firmicues, Proteobacteria) was observed from young to old workers, suggestion the occurrence of age polyethism in food processing. Nest plasticity was also documented by the dissection and characterization of the peculiar architecture of both polycalic nest found in Atlantic Rain Forest and a mound nest of N. ephratae collected in Cerrado region. Nest plasticity in this termite species seems to be drive by the quality and availabity of adequate support tree trunks.