51 resultados para NEOTROPICAL HARVESTMAN
Resumo:
This paper revises the bees currently considered to belong to the genus Rhectomia s.l. and proposes a species phylogeny based on morphological characters, using other Corynurina as outgroups. The results indicate that Rhinocorynura Schrottky renders Rhectomia s.l. paraphyletic. Consequently, Corynurella is removed from synonymy with Rhectomia s.s., and Paracorynurella gen.n. is proposed. The topology among these genera is: outgroup [(Rhectomia s.s. + Rhinocorynura) (Paracorynurella gen.n. + Corynurella)]. Nine species are assigned to Corynurella: C. brokopondoi sp.n., C. caerulea sp.n., C. cognata sp.n., C. decora sp.n., C. harrisoni (Engel), C. mourei Eickwort, C. nigra sp.n., C. singularis sp.n. and C. triangulata sp.n. Three new species are described in Paracorynurella gen.n.: type species P. betoi sp.n., P. excavata sp.n., P. reticulata sp.n.; P. difficillima (Ducke) comb.n. is transferred from Rhinocorynura. Three species are recognized in Rhectomia s.s.: R. catarina sp.n., R. liebherri Engel and R. pumilla Moure. The male of R. liebherri is described for the first time. Keys for the identification of the genera and species are provided.
Resumo:
The Castniidae, or butterfly moths, are characteristically colourful diurnal moths, distributed throughout the tropics except in Africa. The Neotropical representatives forage almost exclusively on monocotyledonous plants and many species are crop pests with more than 60% of the Neotropical castniids found or endemic in Brazil. Research studies that focus on taxonomy, systematics, and morphology of this group are scarce. In this study, Yagra Oiticica, a small genus restricted to south-eastern South America, is revised and the diagnostic morphological characters of male and female genitalia are illustrated. This research is part of long-term study on the Castniidae for future phylogenetic analysis.
Resumo:
Mallodeta Butler and Erruca Walker, revalidated, are redescribed and revised. Mallodeta henceforth includes only its type-species, Glaucopis (Lycorea) clavata Walker, and Erruca is resurrected with seven species: E. deyrolii Walker (type-species), E. consors (Walker), new combination, E. erythrarchos (Walker), new combination, E. cardinalis (Hampson), new combination, E. hanga (Herrich-Schaffer), new combination, E. cruenta (Perty), new combination and E. sanguipuncta (Druce), new combination. Six new synonyms are established, four specific and two generic (junior synonyms in parentheses): Zygaena capistrata Fabricius (=Mallodeta cubana Gaede), Glaucopis (Lycorea) clavata Walker (=M. simplex Rothschild), Erruca deyrolii Walker (=Laemocharis aecyra Herrich-Schaffer and Glaucopis (Hyda) sortita Walker), and Erruca Walker (=Aristodaema Wallengren and Rezia Kirby). Lectotypes are designated to the following species: Erruca deyrolii Walker, Laemocharis deyrollei Herrich-Schaffer, Laemocharis hanga Herrich-Schaffer, Laemocharis aecyra Herrich-Schaffer, Laemocharis norma Herrich-Schaffer, Cosmosoma cardinalis Hampson and Mallodeta sanguipuncta Druce. Illustrations of adults and male and female genitalia of Mallodeta and Erruca are provided, as well as a key to the species of the latter.
Resumo:
The courtship behavior in calopterygid damselflies is well documented; however, the behavior of the large Neotropical genus Mnesarete is still unknown. Thus, here we present the first description of male-female interactions in Mnesarete pudica, a common damselfly in the Neotropical Savanna. The male-female interactions were composed of courtship displays, mounting, and chasing. The courtship behavior lasted 5.23 +/- 1.65 s and is very different from other calopterygids, consisting of hovering flights and the cross display made in front of females rather than on the oviposition site. The arrival and presence of females on a male territory are not sufficient to initiate sexual interactions; the male usually interacts with the female only after a patrolling flight. The females may present three distinct behaviors in response to male approach: (a) warding off signal (31.53%), (b) escape (28.83%), (c) and wing flipping (39.64%), which seems to stimulate male courtship. Females also may sit still, which induces males to react as if females were signaling they are willing to mate. In this paper, we also suggest that male courtship behavior is mediated by female signals.
Resumo:
Populations of Synchaeta jollyae (Shiel & Koste, 1993) (Rotifera), a species recently recorded for the first time in Brazil and South America, were analyzed in reservoirs in Southeast Brazil. Sampling was carried out monthly from August 2006 to July 2007 at Furnas Reservoir in the Rio Grande basin, state of Minas Gerais, and in four cascade reservoirs in the Tiete River basin (Barra Bonita, Bariri, Ibitinga and Nova Avanhandava) state of Sao Paulo, in June and September 2008 and in January and May 2009. Synchaeta jollyae occurred in most samples and periods. From the results obtained it is evident that S. jollyae occurs in water bodies of varied trophic status but reaches larger populations in eutrophic water bodies and during lower temperature periods. The greatest densities of S. jollyae were found in the eutrophic Bariri Reservoir, on the Tiete River, during the winter. Mann-Whitney test confirmed the significant difference between the population densities in periods of high and low temperatures, with populations reaching higher densities at lower temperatures. It is not yet possible to tell whether S. jollyae is a widely distributed species that has been overlooked in previous plankton studies in South America. Wherever these populations of S. jollyae might have originated, it appears to be a species well established and adapted to a wide range of conditions in the Neotropics.
Resumo:
Two new species of Hudsonimyia Roback, 1979 (Diptera: Chironomidae: Tanypodinae) are described and illustrated as male, pupa and larva. The generic diagnosis of pupa is emended and keys to males, pupae and larvae of known species are provided. The different life stages for one of the described species were associated by DNA barcodes.
Resumo:
The present study evaluated the relative growth and allometry of Massartella brieni Lestage and Thraulodes sp. (Leptophlebiidae: Ephemeroptera). The morphometric analysis was based on 23 measurements and was conducted using a multivariate approach. Throughout postembryonic ontogeny, all of the head measurements, including those of the mouthparts, exhibited negative allometric growth. The mesothorax and wing pad exhibited positive allometric growth. The hind legs lengths in M. brieni and the fore and hind legs lengths in Thraulodes sp. exhibited positive allometry. The abdominal length in these two species exhibited positive allometric growth. Positive allometry was also observed along the abdomen width for M. brieni, and isometry was observed for Thraulodes sp. The relative strengthening of the thorax (in preparation for the winged stage) and the relative increase in the abdomen (which may be related to the development of the reproductive structures) during growth indicate that many of the structures that exhibit positive allometric growth are related to the transition from the aquatic to the adult stage of development.
Resumo:
Male secondary sexual characters in Lepidoptera may be present or absent in species that otherwise appear to be closely related, an observation that has led to differences of opinion over the taxonomic usefulness of these structures above the species level. An evolutionary issue raised by this debate is whether male secondary sexual characters (1) can be regained after being lost evolutionarily, (2) are not lost after being evolved, or (3) are 'switched on and off' by genes that regulate development. A second evolutionary issue is the conditions under which male secondary sexual characters might be lost or gained evolutionarily. Because these structures are thought to promote species recognition, theory predicts evolutionary losses to be most likely in allopatry; evolutionary gains to be most likely during the process of secondarily establishing sympatry or during sympatric speciation. We updated the species-level taxonomy of the brilliant emerald winged Neotropical lycaenid butterfly genus Arcas and performed an analysis of phylogenetic relations among species to assess these evolutionary issues. We morphologically detail a scent pouch on the ventral hindwing of Areas and report that six species possess the pouch with androconia, one possesses the pouch without androconia, and the remaining two species have neither pouch nor androconia. In addition, eight Areas species have a morphologically species-specific male forewing scent pad, and one lacks a scent pad. This variation appears to be the result of three evolutionary losses and no gains of male secondary sexual organs. The four Areas species lacking a scent pouch or a scent pad are allopatric with their closest phylogenetic relatives while four of five with both of these structures are sympatric. Although Arcas is a small genus, these results are significantly more extreme than predicted by chance. For taxonomy, this study provides a rationale for the evolutionary loss of male secondary sexual structures and suggests that their absence, but itself, does not indicate a lack of relationship above the species level.
Resumo:
Preliminary observations of the harvestman Leiobunum vittatum found that individuals rub their bodies against the substrate, presenting the possibility of chemical marking. To determine whether or not L. vittatum individuals can detect substrate-borne chemical cues, we compared responses of L. vittatum males and females to substrate-borne male and female cues. We found that individuals of L. vittatum do respond to conspecific cues and that their responses are sex-specific. In response to substrate-borne conspecific cues, male L. vittatum spent more time, engaged in more scraping with their sensory legs I, and engaged in pedipalpal tapping more often in the presence versus absence of conspecific cues (male and female equally). Furthermore, in the presence of conspecific cues, males engaged in two behaviors never observed in females-(a) "fast approach" and (b) "jerking", the latter of which was never observed in the presence of cricket cues. In contrast to males, females did not spend more time on conspecific cues, but did spend more time tapping their pedipalps in the presence of male vs female cues, suggesting an ability to distinguish between them. A final experiment explored the possibility that females could discriminate among males of varying histories of agonistic interactions based upon their chemical cues. We found no support for this hypothesis. Our results demonstrate that L. vitattum do respond to conspecific cues, and introduce the possibility that intraspecific communication may be mediated in part by chemical cues.
Resumo:
During the evolutionary process of the sex chromosomes, a general principle that arises is that cessation or a partial restriction of recombination between the sex chromosome pair is necessary. Data from phylogenetically distinct organisms reveal that this phenomenon is frequently associated with the accumulation of heterochromatin in the sex chromosomes. Fish species emerge as excellent models to study this phenomenon because they have much younger sex chromosomes compared to higher vertebrates and many other organisms making it possible to follow their steps of differentiation. In several Neotropical fish species, the heterochromatinization, accompanied by amplification of tandem repeats, represents an important step in the morphological differentiation of simple sex chromosome systems, especially in the ZZ/ZW sex systems. In contrast, multiple sex chromosome systems have no additional increase of heterochromatin in the chromosomes. Thus, the initial stage of differentiation of the multiple sex chromosome systems seems to be associated with proper chromosomal rearrangements, whereas the simple sex chromosome systems have an accumulation of heterochromatin. In this review, attention has been drawn to this contrasting role of heterochromatin in the differentiation of simple and multiple sex chromosomes of Neotropical fishes, highlighting their surprising evolutionary dynamism.
Resumo:
We revisit species diversity within Oreobates (Anura: Strabomantidae) by combining molecular phylogenetic analyses of the 16S rRNA amphibian barcode fragment with the study of the external morphology of living and preserved specimens. Molecular and morphological evidence support the existence of 23 species within Oreobates, and three additional candidate species (Oreobates sp. [Ca JF809995], Oreobates sp. [Ca EU368903], Oreobates cruralis [Ca EU192295]). We describe and name three new species from the Andean humid montane forests of Departamento Cusco, southern Peru: O. amarakaeri New Species from Rio Nusinuscato and Rio Mabe, at elevations ranging from 670 to 1000 m in the Andean foothills; O. machiguenga, new species, from Rio Kimbiri (1350 m), a small tributary of the Apurimac River, in the western versant of Cordillera Vilcabamba; and O. gemcare, new species, from the Kosnipata Valley at elevations ranging from 2400 to 2800 m. The three new species are readily distinguished from all other Oreobates by at least one qualitative morphological character. Three species are transferred to Oreobates from three genera of Strabomantidae: Hypodactylus lundbergi, Pristimantis crepitans, and Phrynopus ayacucho (for which the advertisement call, coloration in life, and male characteristics are described for first time). Oreobates simmonsi is transferred to the genus Lynchius. Hylodes verrucosus is considered a junior synonym of Hylodes philippi. In addition, H. philippi is removed from the synonymy of O. quixensis and considered a nomem dubium within Hypodactylus. The inclusion of Phrynopus ayacucho in Oreobates extends the ecological range of the genus to the cold Andean puna. Oreobates is thus distributed from the Amazonian lowlands in southern Colombia to northern Argentina, reaching the Brazilian Atlantic dry forests in eastern Brazil, across an altitudinal range from ca. 100 to 3850 m.
Resumo:
Non-myrmecophilous lepidopteran larvae using plants bearing ant attractants such as extrafloral nectaries are good models for studying morphological and behavioural mechanisms against ant predation. Udranomia spitzi (Hesperiidae) is a butterfly whose larvae feed on leaves of Ouratea spectabilis (Ochnaceae), a plant with extrafloral nectaries. We described the early stages of U. spitzi, and used field observations and experiments to investigate the defensive strategies of caterpillars against predatory ants. Larvae pass through five instars and pupation occurs inside larval leaf shelters. Ant-exclusion experiments revealed that the presence of ants did not affect significantly caterpillar survival. Predation experiments showed that vulnerability to ant predation decreased with increase in larval size. The present study showed that predatory ants are not as relevant as demonstrated for other systems, and also illustrates how observational data and field experiments can contribute to a better understanding of the biology and ecology of a species of interest.
Resumo:
Steindachneridion parahybae is a freshwater catfish endemic to the Paraiba do Sul River and is classified as an endangered Neotropical species. An increasing number of conservation biologists are incorporating morphological and physiological research data to help conservation managers in rescue these endangered species. This study investigated the embryonic and larval development of S. parahybae in captivity, with emphasis in major events during the ontogeny of S. parahybae. Broodstocks were artificially induced to reproduce, and the extrusion occurred 200-255 degree-hours after hormonal induction at 24 degrees C. Larval ontogeny was evaluated every 10 minutes under microscopic/stereomicroscopic using fresh eggs samples. The main embryogenic development stages were identified: zygote, cleavage, including the morula, blastula, gastrula phase, organogenesis, and hatching. The extruded oocytes showed an average diameter of 1.10 +/- 0.10 mm, and after fertilization and hydration of eggs, the average diameter of eggs increased to about 1.90 +/- 0.60 mm, characterized by a large perivitelline space that persisted up to embryo development, the double chorion, and the poles (animal and vegetative). Cell division started about 2 minutes after fertilization (AF), resulting in 2, 4, 8 (4 x 2 arrangement of cells), 16 (4 x 4), 32 (4 x 8) and 64 (2 x 4 x 8) cells. Furthermore, the blastula and gastrula stages followed after these cells divisions. The closed blastopore occurred at 11 h 20 min AF; following the development, the organogenetic stages were identified and subdivided respectively in: early segmentation phase and late segmentation phase. In the early segmentation phase, there was the establishment of the embryonic axis, and it was possible to distinguish between the cephalic and caudal regions; somites, and the optic vesicles developed about 20 h AF. Total hatching occurred at 54 h AF, and the larvae average length was 4.30 +/- 0.70 mm. Gradual yolk sac reduction was observed during the first two days of larval development. The first feeding occurred at the end of the second day. During the larval phase, cannibalism, heterogeneous larval growth and photophobia were also observed. This information will be important in improving the artificial reproduction protocols of S. parahybae in controlled breeding programs.
Resumo:
Five new species are described herein for the Neotropical genus Psilochlorops, up to now known only from the type-species, P. clavitibia Duda-P. brunneus sp. n., P. elongatum sp. n., P. flavisoma sp. n., P. nigrifemur sp. n. and P. paganelliae sp. n. All new species are described in detail and illustrated. A key to the species of the genus is provided. The diagnosis of Psilochlorops, after the addition of these species, is emended. A cladistic analysis of the genus indicates that Psilochlorops is monophyletic and show the affinities between the species.
Resumo:
Currently the genus Corynoneura Winnertz comprises 10 species already cited or described for the Neotropical region. In the present paper 15 new species are described for the Neotropics: 12 new species are described from Brazil, five of them are described as male, female, pupa and larva, Corynoneura canchim sp. n., C. diogo sp. n., C. espraiado sp. n., C. humbertoi sp. n., C. salviniatilis sp. n.; three as male, pupa and larva, C. franciscoi sp. n.; C. longiantenna sp. n. and C. renata sp. n.; the species C. sisbiota sp. n. as male, female and pupa; C. bodoquena sp. n. as male and pupa and C. boraceiasp. n. and C. vidiapodeme sp. n. as males. Corynoneura trondi sp. n. is described from Chile (male, pupa), C. guanacaste sp. n. from Costa Rica (male) and C. zempoala sp. n. from Mexico (male). The knowledge of the distribution of Corynoneura fortispicula, C. sertaodaquina, C. septadentata and C. unicapsulata all species described by Wiedenbrug and Trivinho-Strixino (2011) as well as Corynoneura ferelobata Sublette et Sasa is extended. A larval morphotype is also included. Keys for males, females, pupae and larvae to known species of the Neotropical Corynoneura are given.