ABSTRACT. From a series of biological samples collected from different freshwater environments in Costa Rica, Central America, the exotic Asian cyclopoid Mesocyclops thermocyclopoides Harada, 1931 was identified. We analyzed the mor- phology and appendage ornamentation of different Neotropical populations of this species, including specimens from Honduras, southeastern Mexico, and Costa Rica. We also examined Asian specimens from Taiwan, Indonesia, Vietnam, and Thailand, and performed a comparison of the Neotropical and Asian populations including a Principal Component Analysis (PCA). The Neotropical and Asian specimens show subtle morphological variations in the antennules, anten- nae, mandibles, swimming legs 1-4, and fifth legs. Some characters in the Neotropical group appear to diverge from the Asian pattern and the PCA indicated that intercontinental populations of M. thermocyclopoides are far from being homo- geneous. These intra-specific differences are described to expand the known morphological range of this species and to provide the first comparative analysis of an exotic copepod in the Americas. Our analysis suggests that the geographic isolation of the American populations and the subtle morphological divergences with respect to the Asian patterns could be related to speciation processes in the Neotropicalregion, but also intra-Asian differences are reported. In the Neotropicalregion this species appears to be restricted to southeastern Mexico, Central America, and one Caribbean island; its potential as biological control of mosquito might enhance its spread in the region.
In the present study, nuclear DNA content was analyzed in 53 species of Characiformes fish from the Neotropicalregion. Diploid number ranged from 2n = 48 in Astyanax fasciatus, Gymnocorymbus ternetzi and Hyphessobrycon griemi to 2n = 102 in Potamorhina squamoralevis, with a modal number of 54 chromosomes. Nuclear DNA content ranged from 1.70 ± 0.04 pg of DNA per diploid nucleus in Acestrorhynchus pantaneiro to 3.94 ± 0.09 pg in Tetragonopterus chalceus. A general analysis showed a mean value of 2.9 pg of DNA per diploid nucleus. Very similar DNA content values were observed in the species of the family Cynodontidae which showed a variation of 3% between the two genera studied. Small variations were observed between populations of Gymnocorymbus ternetzi, Astyanax fasciatus and Moenkhausia sanctaefilomenae (Characidae, Tetragonopterinae). The subfamilies Tetragonopterinae and Acestrorhynchinae (Characidae) presented the widest range, about 96%. Even in those families in which diploid number and karyotypic formulae were conserved such as the families Anostomidae, Curimatidae, and Prochilodontidae, episodes leading to losses or gains of genetic material became fixed in their evolutionary history.
Myllaena arcana Casey 1911: 239 [original description]. Notman 1920: 708 [characters in key]. Bernhauer & Scheerpeltz 1926: 508 [in world catalog, as synonym of M. minuta (Gravenhorst, 1806)]. Scheerpeltz 1934: 1529 [in world catalog, as synonym of M. minuta (Gravenhorst, 1806)]. Blackwelder 1944: 153 [in checklist from Neotropicalregion, as synonym of M. minuta (Gravenhorst, 1806)]. Moore & Legner 1975: 454 [in Nearctic catalog, as synonym of M. minuta (Gravenhorst, 1806)]. Klimaszewski 1982: 220-221 [redescription, as valid species; lectotype designated]: 183 [in checklist from Nearctic region, as valid species]: 186 [geographic distribution]: 191 [characters in key]: 216 [in cuneata species group]: 217 [distribution map]: 193, 222-223, 240 [illustrations]. Klimaszewski & Génier 1986: 35 [new records from USA]. Klimaszewski & Frank 1992: 400-401 [new records from USA]. Pace 1997: 102 [characters; comparison with M. cornelli Pace, 1997]. Navarrete-Heredia et al. 2002: 191 [in checklist from Mexico].
ABSTRACT. A new species of Stilobezzia Kieffer from the NeotropicalRegion (Diptera, Ceratopogonidae). A new species from the NeotropicalRegion, Stilobezzia (Stilobezzia) pseudopunctulata Cazorla & Ronderos, is described and illustrated based on male and female adults and pupal exuviae. Adults were collected in the Argentinian provinces of Chaco, Formosa, Corrientes and Buenos Aires, and in Santa Cruz, Bolivia. The pupa was collected from mats of floating aquatic macrophytes in a lagoon in Ilha da Marchantería, in the vicinities of Manaus, Brazil. This new species is compared with its similar congener Stilobezzia punctulata Lane, from which it can be mainly distinguished by the wing with only two dark spots, the parameres longer and hook-shaped, the pupal respiratory organ with 11-12 pores and the very short apicolateral processes of the anal segment.
Scale insects associated with Arabica coffee showed the diversity of this group in Brazil and the wide range expansion of several of these species. Most Rhizoecidae scale species associated with Arabica coffee in the Neotropicalregion are not reported occurring in Brazilian Arabica coffee, and it is important because if introduced they may be established in Brazil. Alecanochiton marquesi and P. trilobitiformis are first reported associated with Arabica coffee in Minas Gerais, and Cc. alpinus in Espírito Santo. Dismycoccus texensis remains restricted to Minas Gerais and São Paulo in Arabic coffee. The periods of low coffee prices in international market may influence the spread of scale insect species due to the reduced pest control by Brazilian coffee producers. Elevations, in general, did not seem to influence the spread of scale insect species found on samples. Information obtained in this study are of interest to Brazilian coffee producers, and to other regions. It will help to improve the knowledge of geographical distribution, and spread of scale insects associated with Arabica coffee in the Neotropics, particularly in Brazil.
Hemerobiidae (Insecta, Neuroptera) is a cosmopolitan clade that comprises about 600 described species distributed into 26 genera. Since the publication of revisions to Hemerobius, Megalomus, Nusalala and Nomerobius, new records have been added in literature and taxonomic modifications have occurred at the genus level. The aim of this study was to update a checklist of Hemerobiidae species from Brazil and of specimens deposited at Coleção de Invertebrados do Instituto Nacional de Pesquisa da Amazônia (INPA), Manaus, Brazil; in order to summarize the geographical data of species in Brazilian states and in the NeotropicalRegion and to present new distributional data. The INPA collection holds 19 nominal species (55.2% of the all specimens identified at species level) of hemerobiids into eight genera and six subfamilies, mainly from the NeotropicalRegion; the remaining studied specimens were identified to the genus level. Megalomus marginatus is reported for the first time in Brazil and Nusalala dispar in Ecuador. Moreover, ten new records for the Brazilian states are presented: two to Nusalala tessellata and Hemerobius, and one each to Megalomus impudicus, Notiobiella maculata, Sympherobius ariasi, Megalomus, Nusalala and Sympherobius.
Genus Ornithodoros. Most species are known only from the larval stage, and therefore, the keys for specific diagnosis, although older, refer to this stage (KOHLS et al., 1965; 1969). Currently, the genus comprises around 118 known species around the world (VIAL; CAMICAS, 2009; NAVA et al., 2009; GUGLIELMONE et al., 2010; DANTAS-TORRES et al., 2012; HEATH, 2012; VENZAL et al., 2013a, b); 55 species occur in the Neotropicalregion, and 16 in Brazil. The first species Figures 33-36. Larva of Otobius. 33. Idiosoma dorsal view, showing two pairs of eyes (arrow). 34. Haller’s organ, showing branch-like posterior projections and very long posthalleral setae (arrow). 35. Gnathosoma dorsal view. 36. Gnathosoma ventral view. Scale bars: 33, 90 µm; 34, 30 µm; 35, 40 µm; 36, 60 µm.
Our results suggest that the interaction between pre-adult stages of Z. indianus, D. sturtevanti and D. simulans in oviposition sites can affect their relative abundance over time. Possible results are the elimination of one or more of these competitor species or coexistence among them, as occurred with other invading Drosophilidae species, such as D. malerkotliana and D. simulans, which reached equilibrium with native Neotropical populations, after a population demographic explosion of these species. Monitoring the interactions among Z. indianus
the occurrence of chromosome rearrangements, other mechanisms including changes in DNA content may be in- volved in the speciation process of these groups. Events in- volving the fusion of acrocentric chromosomes which resulted in the origin of biarmed chromosomes, through breaks and losses of small DNA segments corresponding to the pericentromeric region of the chromosomes, could de- termine a substantial loss of genetic material, with conse- quent changes in the nuclear DNA content of the species (Redi et al., 1990; Slijepcevic, 1998; Caputo et al., 1998). Such cytological events could be identified as being re- sponsible for changes occurred in the genomic structure and, consequently, for the species differentiation in these groups.
Damborenea & Cannon (2001), on a neotropical temnocephalans revision, pointed out the absence of any muscular structure (sphincter) in T. chilensis vagina. They also recorded a conic cirrus with a swollen introvert measuring an average of 149 µm in length. All these characteristics differs from T. grisella sp nov. The authors also assert the lack of sphincter on T. talicei. Volonterio (2009), while re-describing T. talicei, has shown the existence of a single conspicuous and asymmetric distal sphincter, pointing out similarities of this species with T. mertoni. Likewise T. talicei and T. mertoni, T. cyanoglandula also have only one vaginal sphincter, which is also distal and asymmetric (Seixas et al. 2015a).