Murillo Lino Bution

Ileum of the Cephalotes ants: A specialized structure to harbor symbionts microorganisms

We conducted comparative morphological studies of the tract digestive of Cephalotes atratus, C. clypeatus and C. pusillus, aiming at describing the relationships among these three species, as well as the histochemical, enzymatic, and ultra-morphological differences of the wall and the contents of the digestive tract, therefore contributing for the understanding of the relationships between symbionts and their host.

Contribution of the Malpighian tubules for the maintenance of symbiotic microorganisms in cephalotes ants

Given the physiological importance of the Malpighian tubules to homeostasis in ants, this study aimed to characterize the enzymology, histology, histochemistry, and ultramorphology of the Malpighian tubules of Cephalotes atratus, C. clypeatus, and C. pusillus, as a contribution for the understanding of this organ, as well as to examine its role in the maintenance of symbiontic microorganisms in the ileum of these ants.

First report of endocytobionts in the digestive tract of ponerine ants

We conducted ultrastructural studies to examine the presence of microorganisms in the midgut of the ant Odontomachus bauri (Ponerinae), as a contribution towards understanding the relationships between microorganisms and their hosts. The presence of microorganisms in this region, including inside the cells, suggests their participation in food digestion as symbiontic organisms and represent a new possibility to exploit food sources in the environment.

Proventriculus of Cephalotes ants: a structural and comparative analysis.

The use of optic microscopy and scanning electron microscopy propitiated the comparative examination of the structure of the proventriculus bulb of Cephalotes atratus, Cephalotes clypeatus and Cephalotes pusillus. This portion of the digestive tract possesses highly sclerotized projections which act in the selection of victuals. This structure is of importance to phylogeny studies and thus was compared with others known species of ants in a dendrogram adapted from Eisner (1957). We did not detect differences among the three studied species in the nature of histochemistry and ultra morphology.

A new strategy of endosymbiont midgut bacteria in ant (Ponerinae).

The location and ultrastructure of bacteria associated with microvilli in the midgut of Odontomachus bauri were examined by transmission electron microscopy. These filamentous type bacteria are the second morphotype described in the midgut of this ant. They colonizes only the ectoperitrophic space, more specifically attaching along microvilli. A thick capsule attaches bacteria to microvilli and protect them from acidic pH and digestive enzymes. Details of the location and association with microvilli are discussed.