Tripanosomatídeos de insetos e plantasanálise do crescimento, diferenciação e divisão celular, biometria e fenômenos sugestivos de sexualidade; valor taxonômico

In this study, fifty trypanosomatid isolates from insect and plants were comparatively analyzed by classic parasitological techniques with intend to know their biological, morphological, and biometric features, to group them according their similarities, to identify characters with diagnostic value, as well as to review taxonomic questions. The isolates were grown at ~27.3oC in "liver infusion tryptose" (LIT) medium or LIT with 20% fetal calf serum (LIT 20%), the latter to enable the growth of the fastidious isolates. All isolates were analyzed between 48\F02D144 h of cultivation, at 24 h intervals, to evaluate their growth rates, and to prepare Giemsa stained smears for studies under optical microscope (1,000\F0B4). The measures and the percent of each developmental stage and the division types were determined. Peculiar cells and pairs suggesting steps of a sexual phenomenon were also searched. With of exception three species, which are awaiting further analyses, the trypanosomatids under study were classified in fourteen groups (morphobiodemes), seven of them being identified with previously named genera, whose diagnose was reviewed in the present study: Crithidia, Wallaceina, Angomonas, Strigomonas, Herpetomonas (sensu Prowazek), Cercoplasma e Phytomonas. Aiming to better define the complex differentiation pattern found in the choanomastigote-shaped trypanosomatids, we proposed the names prochoanomastigote, parachoanomastigote and metachoanomastigote, respectively, to those stages having ante-, para- and postnuclear kinetoplast, besides the name endochoanomastigote to those forms with internal bent flagellum In Angomonas genus, the metachoanomastigotes were the predominant forms (mean \F03E 55.0%), whereas in Wallaceina predominated the endochoanomastigotes (mean \F03E 50.0%). Crithidia species did not present these two stages or they were seen at low mean rates (\F0A3 2.3%). However, their small choanomastigotes, mainly aflagellates, either free or adhered to each other (haptomonads), were helpful markers for their identification. In Strigomonas, the parachoanomastigotes predominated, the endochoanomastigotes and aflagellate haptomonads were absent, and the metachoanomastigotes occurred at low mean rate (~5.0%). The Herpetomonas genus, as it has been identified by nearly one century, actually contains a mixture of taxa. Based on descriptions and illustrations from several pioneering authors, only the so-called H. muscarum ingenoplastis is similar to the type-species of this genus (H. muscarum), presenting very large promastigotes, mainly biflagellates, with a great and peculiar kinetoplast. The others species identified as Herpetomonas are very distinct from H. m. ingenoplastis, and their generic classification needs revision. The great diversity of the species identified in the Leptomonas genus was confirmed, and they were classified into seven groups. Accounting the uncertainties about the authenticity of the typespecies (L. butschlii), it is difficult to know if any species studied herein could be classified as Leptomonas. However, it is noteworthy that two cystogenic isolates from phytophagous hemiptera presented morphological similarity with the first insect trypanosomatid classified in this genus (L. jaculum). Solely L. mirabilis could be associated to a previously reported genus (Cercoplasma), in which it was already been placed. This species is suggested as reference, and it presents a very complex combination of features, among them the "giant" twisted forms (70\F02D200\F06Dm), which are of great diagnostic value The Phytomonas species basically present promastigotes and a variable percent of twisted cells. However, at least, two features could easily distinguish them: their elongated aflagellate forms, only free in cultures, usually smaller than the flagellate ones, and their peculiar division process, which gives rise either to two cells with very different flagellum size, or one having flagellum and the other not. In the present study, it was evidenced that the cellular division can also generate distint stages, besides multiplying highly differentiated forms. It was also confirmed that stages with postnuclear kinetoplast, internal bent flagellum, and the twisted cells are not exclusive from a single genus of the Trypanosomatidae family. Peculiar cells and pairs, previously described as suggestive steps of a sexual phenomenon, were also found in Crithidia, Leptomonas e Phytomonas species, but mainly in the so-called Herpetomonas, which more frequently displayed possible events of migration and fusion of nuclei. Our studies confirmed that it is possible to identify and classify trypanosomatids by classical parasitological approaches, taking into account their set of features, these rather known by analyses under standardized experimental conditions, and including reference strains