7 research outputs found

    Morphometric differences in the grasshopper Cornops aquaticum (Bruner, 1906) from South America and South Africa

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    The semi-aquatic grasshopper Cornops aquaticum is native to South America and inhabits lowlands from southern Mexico to Central Argentina and Uruguay. It is host-specific to aquatic plants in the genera Eichhornia and Pontederia. A quarantine population has existed in South Africa for 10 y, and it is planned to release it there as a biological control agent of water hyacinth, E. crassipes. Various studies of C. aquaticum are coordinated under HICWA (www.mpil-ploen.mpg.de). This paper compares the morphometry of the release population and 11 native populations in South America. We tested four hypotheses: 1) South African and South American populations of C. aquaticum differ in morphology; 2) the South African laboratory population is more similar to other isolated populations in South America than to nonisolated populations; 3) morphology differs across sites; 4) morphology differs with host plant. South African populations differed from continental nonisolated populations, but not from continental isolated ones. Isolated populations presented smaller individuals than nonisolated, but there was also a change in male morphology: while in nonisolated populations male wing length was similar to their body length, in isolated populations, male wings were smaller than body length. Females were larger when on Eicchornia azurea than on E. crassipes, while males presented larger wings than their body on E. azurea, and similar lengths on E. crassipes. These morphological changes may have resulted from phenotypic plasticity, selection for small size, or because of a loss of genetic diversity in quantitative traits.Fil: Adis, Joachim. Institute for Limnology; AlemaniaFil: Sperber, Carlos F. Universidade Federal de Viçosa; BrasilFil: Brede, Edward G. Institute for Limnology; AlemaniaFil: Capello, Soledad. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe. Instituto Nacional de LimnologĂ­a. Universidad Nacional del Litoral. Instituto Nacional de LimnologĂ­a; ArgentinaFil: Franceschini, Maria Celeste. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Nordeste. Centro de EcologĂ­a Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de EcologĂ­a Aplicada del Litoral; ArgentinaFil: Hill, Martin. Rhodes University; SudĂĄfricaFil: Lhano, Marcos G. Universidade Federal de Viçosa; BrasilFil: Marques, MarinĂȘ. A;z M.. Universidade Federal de Mato Grosso; BrasilFil: Nunes, Ana L.. MusĂ©u Paraense EmĂ­lio Goeldi; BrasilFil: Polar, Perry. CAB International; Trinidad y Tobag

    Taxonomy based on science is necessary for global conservation

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    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & NemĂ©sio 2007; Donegan 2008, 2009; NemĂ©sio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    Variação do peso fresco em Cornops aquaticum (Bruner) (Orthoptera, Acrididae) associado a Eichhornia azurea (Sw) Kunth (Pontederiaceae) em uma baía no Pantanal de Poconé, Mato Grosso Variation of the fresh weight in Cornops aquaticum (Bruner) (Orthoptera, Acrididae) associated with Eichhornia azurea (Sw) Kunth (Pontederiaceae) in a bay in the Pantanal of Poconé, Mato Grosso

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    Variação do peso fresco em Cornops aquaticum (Bruner) (Orthoptera, Acrididae) associado a Eichhornia azurea (Sw) Kunth (Pontederiaceae) em uma baĂ­a no Pantanal de PoconĂ©, Mato Grosso. Cornops aquaticum (Bruner, 1906) (Orthoptera, Acrididae) desenvolve seu ciclo de vida sobre macrĂłfitas aquĂĄticas da famĂ­lia Pontederiaceae. Como os gafanhotos sĂŁo capazes de responder Ă s mudanças sazonais, a alternĂąncia de perĂ­odos que ocorre no Pantanal pode refletir em sua biologia. Este estudo foi desenvolvido no Pantanal de PoconĂ© - MT, com o objetivo de avaliar possĂ­veis variaçÔes no peso fresco dos adultos e ninfas de C. aquaticum. Durante o perĂ­odo de março/2006 a fevereiro/2007 coletaram-se mensalmente, 50 indivĂ­duos de C. aquaticum. Um total de 600 indivĂ­duos foi avaliado, sendo 43,5 % adultos e 56,5 % ninfas. Os maiores valores de peso fresco total ocorreram nos meses de setembro (9,106g; 0,182g/indivĂ­duo) e outubro/2006 (8,865g; 0,177g/indivĂ­duo) e os menores em março/2006 (3,413g; 0,068g/indivĂ­duo). Nos indivĂ­duos adultos os maiores pesos frescos foram registrados em setembro/2006 (8,680g; 0,223g/indivĂ­duo) e outubro/2006 (8,654g; 0,234g/indivĂ­duo), no final do perĂ­odo de seca, e o menor em março/2006 (1,792g; 0,138g/indivĂ­duo), durante o perĂ­odo de cheia. As ninfas tiveram o maior peso fresco em abril/2006 (2,913g; 0,076g/indivĂ­duo) inĂ­cio da vazante, enquanto o menor peso fresco ocorreu em outubro/2006 (0,211g; 0,016g/indivĂ­duo) inĂ­cio da enchente. Apenas a variação no peso fresco mĂ©dio das fĂȘmeas foi significativa (f = 6,43; p = 0,001), com os maiores registros durante o perĂ­odo de enchente, o que pode evidenciar uma estratĂ©gia reprodutiva.<br>Cornops aquaticum (Bruner, 1906) (Orthoptera, Acrididae) develops its life cycle on aquatic macrophyte of the Pontederiaceae family. As grasshoppers are able to respond to the seasonal changes, the alternation of periods that occurs in the Pantanal may reflect in their biology. This study was carried out in the Pantanal of PoconĂ©- MT, with the aim of evaluating possible variations in the fresh weight of the adults and nymphs of C. aquaticum. From March/2006 to February/2007, 50 individuals of C. aquaticum were collected each month. A total of 600 individuals was assessed, 43.5% of which were adults and 56.5% nymphs. The highest values of total fresh weight occurred in September (9.106g; 0.182g/individual) and October/2006 (8.865g; 0.177g/individual) and the lowest in March/2006 (3.413g; 0.068g/individual). Among the adult individuals the highest fresh weight was registered in September/2006 (8.680g; 0.223g/individual) and October/2006 (8.654g; 0.234g/individual), at the end of the dry period, and the lowest in March/2006 (1.792g; 0.138g/individual) during the flood period. The nymphs had the highest fresh weight in April/2006 (2.913g; 0.076g/individual) at the beginning of the draining period, whereas the lowest fresh weight occurred in October/2006 (0.211g; 0.016g/individual) at the beginning of the flood period. Only the variation in the average fresh weight of females was significant (f = 6.43; p = 0.001) with the highest recordings occurring during the flood period, what may show a reproductive strategy

    Morphometry of the nymphal stages in Cornops aquaticum (Acrididae: Leptysminae) from Argentina

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    Cornops aquaticum estĂĄ ampliamente distribuĂ­da en toda LatinoamĂ©rica y su ciclo biolĂłgico estĂĄ estrechamente relacionado a Eichhornia crassipes (Mart.) Solms y Eichhornia azurea KUNTH (Pontederiacea). La correcta determinaciĂłn de los estadĂ­os ninfales de C. aquaticum resulta de fundamental importancia para conocer la estructura de las poblaciones en una determinada regiĂłn. El objetivo del presente trabajo es evaluar la utilidad de los caracteres morfomĂ©tricos de las ninfas de C. aquaticum para determinar los distintos estadĂ­os ninfales. Para esto se realizĂł la crĂ­a de ninfas de primer estadĂ­o en laboratorio, en Corrientes (N= 29, 28 y 24) y Santa FĂ© (N= 26, 16), donde se encuentran diferentes condiciones de temperatura e insolaciĂłn. Las ninfas fueron pesadas y medidas al inicio de la experiencia y despuĂ©s de producida la ecdisis: distancia desde el fastigium hasta el final de las pterotecas o pronotum (A), distancia desde el fastigium hasta el final del abdomen (B), longitus del fĂ©mur posterior (H), longitud de la antena (L), nĂșmero de antenĂłmeros (N° Ant. ) y peso fresco (Peso). La longitud del fĂ©mur posterior mostrĂł ser la medida mĂĄs constante en cada estadĂ­o ninfal. En contraste con otros caracteres, presenta la ventaja de ser preciso y constituye ademĂĄs una medida sencilla de registrar cuando se trabaja con un gran nĂșmero de individuos. Con la informaciĂłn morfomĂ©trica, se espera complementar los estudios morfolĂłgicos ya existntes y contribuir al conocimiento ecolĂłgico de la especie.Cornops aquaticum is a widely distributed species in Latin America and has a life cycle associated with Eichhornia crassipes (MART.) SOLMS and E. azurea (SW.) KUNTH (Pontederiaceae). The correct determination of the nymphal stages in C. aquaticum is important to study the population structure in a specific region. The purpose of this study is to evaluate if morphometric characters can be used to determine the different nymphal stages in C. aquaticum. For this reason, first-stage nymphs were reared at two localities (Corrientes: N = 29, 28, 24; Santa Fe: N = 26, 16) under different conditions of temperature and insolation. After hatching and after each moult, fresh weight ("Peso") of nymphs was determined and measurements of the following morphometrical characters were taken: distance from fastigium to end of pterothecas or pronotum (A), distance from fastigium to end of abdomen (B), length of hind femur (H), length of antenna (L), and number of antennal segments (N Ant.). Length of the hind femur (H) was the most constant and precise character in each nymphal stage, subjected to little measuring bias and easy to measure when working with a high population density. Morphometrical and morphological data are expected to contribute to the ecological knowledge of this species.Fil: Franceschini, Maria Celeste. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Nordeste. Centro de EcologĂ­a Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de EcologĂ­a Aplicada del Litoral; ArgentinaFil: Capello, Soledad. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe. Instituto Nacional de LimnologĂ­a. Universidad Nacional del Litoral. Instituto Nacional de LimnologĂ­a; ArgentinaFil: Lhano, Marcos G.. Universidade Federal do Reconcavo da bahĂ­a; BrasilFil: Adis, Joachim. Instituto Max Plank para LimnologĂ­a; AlemaniaFil: de Wysiecki, Maria Laura. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - La Plata. Centro de Estudios ParasitolĂłgicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios ParasitolĂłgicos y de Vectores; Argentin

    Taxonomy based on science is necessary for global conservation

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