RESUMO
The first records of outbreaks of the Pine Spittle bug Ocoaxo assimilis Walker were recently identified from Puebla, Mexico, which promoted more than 2600 ha of forest foliar fall. Beyond the taxonomic and distribution information of this species, the basic traits of its biology remain unknown. This study aims to describe some biological aspects of O. assimilis, in a natural pine forest at Nicolás Bravo, Puebla (NB). Using morphological characteristics and a phylogenetic analysis of a fragment of cytochrome oxidase subunit I mtDNA (COI), immature instars with adults were studied; the instar number was determined by means of a multivariate analysis of 19 morphological characteristics of 121 specimens. The systematic sampling to evaluate the occurrence of nymphal specimens during a year, plus host selection experiments, allowed for determination of the abundance over time, voltism, and host preferences. Phylogenetic analysis of the COI supported that both nymphs and adults collected in NB correspond to O. assimilis. Principal coordinate analysis supported the existence of five nymphal stages. Field sampling and host selection experiments indicated that this species displays a single generation per year, is associated with the rainy season, and that specimens from the three first nymphal stages feed on roots of eight host species (one grass, four herbaceous species, one bush, and two trees). From the fourth instar, the insects feed on pine roots to complete their development, and when they are adults, they migrate to needles of young or mature pine stands of Pinus pseudostrobus to feed and reproduce.
RESUMO
The soft scale insect genus Paralecanium Cockerell (Hemiptera: Coccomorpha: Coccidae), mainly characterised by the possession of fan-shaped marginal setae, has never been revised and most of the species currently recognised were described in the early part of the twentieth century. The present revision is based on the morphology of the adult females and redescribes and illustrates all 34 species or subspecies previously included in the genus. These three subspecies have been raised to full specific rank, namely P. expansum javanicum (Green) to P. javanicum (Green) stat. n.; P. expansum rotundum (Green) to P. rotundum (Green) stat. n. and P. frenchii macrozamiae (Fuller) to P. macrozamiae (Fuller) stat. n. Of the remaining previously recognised species, three have been made junior synonyms: P. album Takahashi is here considered to be a junior synonym of P. metallicum (Green), syn. n.; P. angkorense Takahashi is considered to be a junior synonym ofP. cocophyllae Banks, syn. n.; and P. limbatum Green is considered to be a junior synonym of P. geometricum (Green), syn. n. Paralecanium marianum Cockerell from Brazil is clearly not closely related to Paralecanium and so a new genus, Mariacoccus Hodgson Williams gen. n., has been introduced to take it and the adult female is redescribed and illustrated; comparison of the adult female of M. marianus with that of Coccus lizeri (Fonseca) showed that the latter species is a junior synonym of M. marianus (Cockerell), syn. n. Based on the morphology of the above species and on the new species mentioned below, two new genera have been introduced: Insularicoccus Hodgson Williams gen. n. (type species P. carolinensis Beardsley), and Discochiton Hodgson Williams gen. n. (type species D. martini Hodgson, spec. n.). This brings the number of soft scale genera with fan-shaped marginal setae to three. Diagnoses of each of these 3 genera are presented, along with a key to the genera based on adult female morphology. The species that have been left in Paralecanium Cockerell are: P. calophylli (Green), P. frenchii (Maskell), P. geometricum (Green), P. hainanense Takahashi, P. machili Takahashi, P. macrozamiae (Fuller), P. maculatum Takahashi, P. marginatum (Green), P. maritimum (Green), P. minutum Takahashi, P. neomaritimum Takahashi, P. ovatum Morrison, P. pahanense Takahashi, P. peradeniyense (Green), P. planum (Green) and P. zonatum (Green). The species transferred to Discochiton as comb. n. are: P. album Takahashi, P. cocophyllae Banks, P. expansum (Green), P. javanicum (Green), P. luzonicum Cockerell, P. malainum Takahashi, P. mancum (Green), P. metallicum (Green), P. milleri Takahashi, P. pseudexpansum (Green), P. quadratum (Green), P. rotundum (Green),P. trifasciatum (Green) and P. vacuum Morrison. The only species transferred to Insularicoccus is the type species, namelyP. carolinense (Beardsley), comb. n. In addition, adult females of the following 11 new species are described and illustrated in the genus Paralecanium (as defined here) spec. n.: P. acinaces Hodgson, P. busoense Hodgson, P. claviseta Hodgson, P. comperei Hodgson, P. cypripedium Hodgson, P. elongatum Hodgson, P. leei Hodgson, P. morobeense Hodgson, P. neoguineense Hodgson, P. palawanense Hodgson and P. vacerra Hodgson. In addition, the following 8 species are described and illustrated as Discochiton spec. n.: D. browni Hodgson, D. crenulatum Hodgson, D. diplodiscus Hodgson, D. martini Hodgson, D. papillatum Hodgson, D. paucipedis Hodgson, D. sarawakense Hodgson and D. seychellarum Williams Hodgson, and 1 species of Insularicoccus is described as new and illustrated, namely I. syzygium Hodgson spec. n. Keys, based on adult female morphology, are provided for separation of all the species in each genus. As part of this revision, the morphological characters used to diagnose species in this group of genera are re-evaluated and a number of new characters found; greater emphasis has been placed on some character-states, so the basic morphology of this group of genera is also described. Lectotypes have been designated for 22 species, namely: Lecanium calophylli Green; L. expansum Green; L. expansum javanicum Green; L. expansum metallicum Green; L. expansum rotundum Green; rotundum Green; L. geometricum Green; L. limbatum Green; L. mancum Green; L. marginatum Green; L. maritimum Green; L. peradeniyense Green; L. planum Green; L. pseudexpansum Green; L. quadratum Green; L. trifasciatum Green and L. zonatum Green. Also: Paralecanium album Takahashi; P. hainanense Takahashi; P. malianum Takahashi; P. marianum Cockerell; P. neomaritimum Takahashi and P. vacuum Morrison. Finally, an example of the first-instar nymphs, second-instar males and second/third instar females of both Paralecanium and Discochiton are described and illustrated and compared with those already known in the tribe Paralecaniini.
Assuntos
Hemípteros , Ninfa , Animais , Brasil , Besouros , Feminino , Masculino , OrchidaceaeRESUMO
Postembryonic development, fecundity and food consumption of Dichroplus exilis (Orthoptera: Acrididae) under controlled conditions. Dichroplus exilis is a widely distributed species in Southern South America. Although there have been reports of D. exilis as an agricultural pest, some recent observations suggest that the damage attributed to D. elongatus may actually have been caused by D. exilis. This study was conducted to determine the postembryonic life cycle stages, fertility and food consumption of this species under controlled conditions (30°C, 14L-10D, 40% RH).Individuals employed belong to the laboratory-hatched first generation (F1), from adults (n=64, ♀=28, ♂=36) collected in natural grasslands near Rafaela, Santa Fe province in North- Eastern Argentina. Three cohorts of 16, 17 and 20 individuals were monitored independently in acetate tubes on a daily basis, until death of the last insect. Average fecundity was 381.84, 38.54 eggs per female. Egg-pod incubation time was 14.4, 1.08 days and six nymphal instars were recorded. Nymphal development time was 41.38, 0.71 days (I=8.73, 0.20; II=6.38, 0.24; III=5.64, 0.33; IV=7.15; 0.43; V=9.76, 0.54; IV=7.85, 0.95). The recorded food consumption was 9.89, 1.08 (mg/ind/day) for nymphs IV, 18.04, 0.73 (mg/ind/day) for nymphs V-IV, 16.76, 1.06 (mg/ind/day) for pre-reproductive males, 28.09, 1.81 (mg/ind/day) for pre-reproductive females, 7.71, 0.91 (mg/ind/day) for reproductive males and 13.06, 0.71 (mg/ind/day) for reproductive females, while the average adult food consumption, regardless of sex and reproductive status, was 16.41, 4.32mg/day. Average food consumption of adult females was 17.47, 1.15mg, and was significantly higher than that of males (10.83, 0.91mg). Data obtained in this study showed that D. exilis exhibits at least some of the biological attributes needed to configure an actual or potential agricultural pest, albeit not yet recognized as such. Field monitoring ...
La Subfamilia Melanoplinae tiene una relevancia central dentro de la acridiofauna Argentina. Varias especies suelen ser numéricamente dominantes en las comunidades de acridios del país y algunas constituyen serias plagas. El objetivo de este trabajo fue conocer el ciclo de vida postembrionario, la fecundidad y supervivencia de las hembras y el consumo de alimento de Dichruplus exilis bajo condiciones controladas (30°C; 40%HR y 14L-10O). Para ello se realizó el seguimiento de tres cohortes de 16, 17 y 20 individuos. El tiempo de incubación fue de 14.4±1.08 días. La duración del desarrollo ninfal fue 41.38; 0.71 días (I 8.73; 0.20, II 6.38; 0.24, III 5.64; 0.33, IV 7.15; 0.43, V 9.76; 0.54; IV 7.85; 0.95); la fecundidad promedio fue de 381.84, 38.54huevos/hembra. El consumo registrado fue de 9.89; 1.08 (mg/ind./día) para las ninfas de IV, 18.04; 0.73 (mg/ind./día) para las de V y IV, mientras que el consumo promedio de los adultos, sin diferenciar sexo y estado reproductivo, fue de 16.41; 4.32mg/día. Estos parámetros, al ser comparados con los de otras especies afines, indican que D. exilis exhibe atributos biológicos que condicen con los de otros melanoplinos considerados plaga.
Assuntos
Animais , Feminino , Masculino , Comportamento Alimentar/fisiologia , Gafanhotos/crescimento & desenvolvimento , Estágios do Ciclo de Vida/fisiologia , Animais de Laboratório , Fertilidade/fisiologia , Gafanhotos/classificação , Gafanhotos/fisiologiaRESUMO
The three nymphal instars of Abrocomophaga hellenthali Price & Timm, 2000 are described and compared with both sexes of the adult stage. The most remarkable quali and quantitative body features of all instars are cathegorized and its progression along the development stated.
RESUMO
The three nymphal instars of Abrocomophaga hellenthali Price & Timm, 2000 are described and compared with both sexes of the adult stage. The most remarkable quali and quantitative body features of all instars are cathegorized and its progression along the development stated.