ABSTRACT
Male Tettigoniidae emit sound to attract conspecific females. The sound is produced by stridulation. During stridulation the forewings open and close, but it is during the closing stroke that the scraper contacts the file teeth to generate the predominant sound components, which are amplified by adjacent wing cells specialized in sound radiation. The sounds usually exceed the sonic boundary and might occur above 40 kHz, reaching extreme ultrasonic frequencies of 150kHz in some species. Here we test the hypothesis that Tettigoniidae species should prefer microhabitats that favour efficient signal transmission, i.e. that there is a relationship of sound frequency with the vertical distribution of the species (from ground to canopy) at Gorgona National Natural Park, Colombia. We sampled 16 trees and four different altitudinal levels between 1 and 20m above the understory vegetation. We placed collecting blankets separated by vertical distances of 5m, and knocked insects down using the technique known as fogging. We found no correlation between vertical distribution and carrier frequency, but there was a preference for open spaces (below the canopy and above the understory) in species using extreme ultrasound. This is the first quantitative description of the vertical distribution in neotropical species of the family Tettigoniidae and its relationship to the calling song frequency. Rev. Biol. Trop. 62 (Suppl. 1): 289-296. Epub 2014 February 01.
Los machos de Tettigoniidae producen sonido frotando las alas anteriores para atraer a sus hembras coespecíficas con fines reproductivos (mecanismo conocido como estridulación). Un borde esclerotizado (o raspador) en el ala derecha es frotado sobre una vena modificada con dientecillos en el ala izquierda. Durante la estridulación las alas abren y cierran, pero es durante el cierre que el raspador contacta los dientecillos de la lima y produce vibraciones que son amplificadas por celdas adyacentes especializadas para radiar sonido. Sonidos que superen los 20 000Hz, se consideran ultrasónicos, en los Tettigoniidae, la mayoría de los cantos superan el umbral sónico y pueden ocurrir a más de 40 000Hz, con casos extremos de hasta 148 000Hz. La esencia de este trabajo es el estudio de esta gama espectacular de frecuencias de la familia Tettigoniidae y su relación con la distribución vertical de los individuos en las especies que habitan en Gorgona. Se muestrearon 16 árboles a cuatro niveles diferentes de altitud entre 1 y ~20m sobre el sotobosque, instalando sabanas colectoras a intervalos de 4-5m. Los insectos se colectaron mediante el método de nebulización térmica. El análisis indica que no hay correlación entre la distribución vertical de las especies y la frecuencia del canto. Sin embargo se observó una preferencia por espacios abiertos en especies que cantan a frecuencias extremas. Este estudio representa la primera descripción cuantitativa de la distribución vertical de Tettigoniidae Neotropicales y su relación con la frecuencia del canto.
Subject(s)
Orthoptera/classification , Gryllidae/anatomy & histology , Grasshoppers/anatomy & histology , Acoustics , Colombia , Animal Distribution , NoiseABSTRACT
The karyotypes of five species of Brazilian Pseudophyllinae belonging to four tribes were here studied. The data available in the literature altogether with those obtained with species in here studied allowed us to infer that 2n(♂)=35 is the highest chromosome number found in the family Tettigoniidae and that it is present in species belonging to Pseudophyllinae, Zaprochilinae and in one species of Tettigoniinae. In spite of that all five species exhibit secondary karyotypes arisen surely by a mechanism of chromosomal rearrangement of centric fusion, tandem fusion and centric inversion types from those with 2n(♂)=35 and FN=35, they share some common traits. The X chromosome is submetacentric (FN=36), heteropicnotic during the first prophase, the largest of the set but its size is rather variable among the species and the sex chromosomal mechanism is of the XO( ♂ ), XX( ♀ ) type. The chromosomal rearrangements involved in the karyotype evolution of the Pseudophyllinae and its relationship with those of the family Tettigoniidae are discussed and we propose that the basic and the ancestral karyotype of the Tettigoniidae is formed by 2n(♂)=35, FN=35 and not by 2n(♂)=31, FN= 31, as usually accepted.
Subject(s)
Animals , Male , Orthoptera/classification , Orthoptera/genetics , Brazil , Cytogenetic Analysis , KaryotypingABSTRACT
The thirteen species of Phaneropterinae here studied can be arranged in four different groups according to their basic karyological traits. All of them share the same kind of chromosomal sex determining mechanism with X0(male) and XX(female). The X chromosome differs among species and always appears heteropycnotic during prophase I, it is the largest in the set and segregates precociously during anaphase I. Among the species, the karyotypes varies in fundamental number between 31 to 21. The meaning of these significant changes in the karyotypes in relation to the phylogeny within some large taxonomic group of species is discussed.
As treze espécies de Phaneropterinae estudadas neste trabalho podem ser organizadas em quatro diferentes grupos tomando como referência suas características cariotípicas. Todas possuem sistema cromossômico de determinação sexual do tipo X0(masculino), XX(feminino). O cromossomo X é sempre heteropicnótico durante a prófase I, tem dimensões e morfologias variáveis nas diferentes espécies mas é sempre o maior elemento do cariótipo, além de apresentar segregação precoce durante a anáfase I. O número cromossômico fundamental (NF) varia de 21 a 32. Neste trabalho, são discutidos os significados evolutivos das variações cariotípicas encontradas e suas correlações filogenéticas com outros grupos de espécies pertencentes à mesma subfamília.
Subject(s)
Orthoptera/classification , Orthoptera/geneticsABSTRACT
Se revisa el género Cephalocoema Serville, 1839 y sus especies constituyentes, en base a al examen de los ejemplares tipo. Se agregan otras nuevas y se da información primaria de aquellas que deberán ser sinonimizadas a otros géneros. Cada especie es estudiada en base a su morfología externa, sus caracteres genitales tanto femeninos como masculinos y se ubican las localidades tipo en un mapa de la Región Neotropical, realizado sobre el estudio de las zonas fitogeográficas, por medio del cual se obtiene un patrón aproximado de las características de los hábitats preferidos por estas especies y por ende, del género en su totalidad.
The genus Cephalocoema Serville, 1839 is revised by the study of its type-species and additional ones. New species are described and synonymies are made. Each species is studied in its morphological features and genital characters, both male and female. Type localities are marked in Biogeographical regions map, which let us to get a pattern of distribution related with the habitat preferences of each species, for the whole genus.