Life cycle of Retracrus johnstoni Keifer (Acari: Phytoptidae)

Abstract

Neotropical Entomology 32 (2):197-201 (2003) Ciclo de Vida de Retracrus johnstoni Keifer (Acari: Phytoptidae) RESUMO -Os ácaros Eriophyoidea estão comumente associados a palmeiras, entretanto poucas espécies têm sido relatadas causando danos econômicos nessas plantas. Uma exceção é Retracrus johnstoni Keifer, praga de Bactris gasipaes Kunth, planta utilizada na produção de palmito. R. johnstoni tem sido encontrado em grande número de arecáceas no Sudeste do Brasil. O objetivo deste trabalho foi estudar a biologia deste ácaro em laboratório. Seções de folhas da palmeira Syagrus romanzoffiana (Cham.) Glassman com cerca de 15 folíolos foram conservadas mantendo suas bases em água destilada. Aproximadamente 20 adultos de R. johnstoni foram transferidos para cada folíolo para oviposição. Após 24h, os ácaros foram removidos, deixando-se apenas um ovo por folíolo. Diariamente os ovos e os estágios subseqüentes foram examinados para determinação do ciclo de vida, taxa de oviposição e sobrevivência. Cada estágio imaturo de R. johnstoni teve duração de aproximadamente sete dias, totalizando aproximadamente 20,5 dias para o desenvolvimento de ovo a adulto. A razão sexual foi de aproximadamente duas fêmeas para cada macho. A fecundidade total foi de cinco ovos por fêmea. Formas imaturas e adultos eram cobertos por uma camada de material branco secretado por eles. O espermatóforo de R. johnstoni é semelhante ao de outras espécies da superfamília, e consiste em uma cabeça de aproximadamente 6 x 6 µm e uma base de aproximadamente 6 µm de comprimento. Os danos apresentam-se como manchas escuras na superfície inferior e manchas amareladas nas regiões correspondentes da superfície. As manchas foliares aumentam progressivamente, coalescem e a folha morre e cai prematuramente. PALAVRAS-CHAVE: Biologia, Eriophyoidea, Arecaceae ABSTRACT -Eriophyoid mites are commonly associated to palm trees, although few of them have been reported causing economic damage to those plants. One exception is Retracrus johnstoni Keifer, a pest of Bactris gasipaes Kunth, plant used for palm heart production. R. jonhstoni is frequently found in large numbers on Arecaceae in southeast Brazil. The biology of this mite was studied under laboratory condition. Sections of leaves of the palm tree Syagrus romanzoffiana (Cham.) Glassman, with ca. 15 leaflets, were kept alive by maintaining their bases in distilled water. Ca. 20 field collected adults of R. johnstoni were transferred onto each leaflet for oviposition. After 24h, mites were removed, leaving only one egg laid. Once a day, the eggs and the subsequent stages were examined to determine the life cycle, oviposition rate and survivorship. Each immature stage of R. johnstoni lasted ca. seven days, corresponding to ca. 20.5 days for immature development. The sex ratio was ca. two females per male. Total fecundity was slightly over five eggs per female. Immature and adult mites secreted a layer of white material, which covered their bodies. Spermatophores of R. johnstoni resemble those of other species in ...

Demographic parameters of Phyllocoptes adalius (Acari: Eriophyoidea) and influence of insemination on female fecundity and longevity

“…Results showed that P. adalius has a short developmental period; a slightly shorter or similar length of development was observed for Aculops lycopersici (Massee) (Abou-Awad 1979 ; Haque and Kawai 2003 ) and Metaculus mangiferae (Attiah) (Abou-Awad et al 2011b ). Some other species need longer periods to reach adulthood; up to 20.5 days for Retracarus johnstoni Keifer, a dangerous pest of palm trees (Gondim and de Moraes 2003 ). Juvenile development is longer for P. fructiphilus , a species closely related to P. adalius (Kassar and Amrine 1990 ).…”

“…However, and despite the importance of eriophyoids, either as pests or biological agents, knowledge on their biology and ecology is limited. To date, detailed studies on the life history of eriophyoids have been performed for only a few species (Sabelis and Bruin 1996 ; Abou-Awad et al 2000 , 2005 , 2011a , b ; Ebrahim 2000 ; Shi 2001 ; Gondim and de Moraes 2003 ; Haque and Kawai 2003 ; Ansaloni and Perring 2004 ; Skoracka and Kuczyński 2004 , 2006 ; Ozman and Goolsby 2005 ; Walton et al 2010 ; Stoeva et al 2011 ).…”

How small you can go: Factors limiting body miniaturization in winged insects with a review of the pantropical genus Discheramocephalus and description of six new species of the smallest beetles (Pterygota: Coleoptera: Ptiliidae)

“…200 µm, and range from 80 µm to 500 µm (Lindquist, 1996). The smallest eriophyoid mites normally only have a single egg per female at any one time (Gondim & Morales, 2003) and their males are smaller than the females (Colwell, 2000). These mites, however, are not egg-parasitoids but freeliving organisms that feed on plant tissue.…”

What’s “cool” on eriophyoid mites?

“…The procedure developed by De Silva and Fernando (2008) to successfully mass rear Aceria guerreronis Keifer on embryo culture seedlings for up to 5 weeks offers promise for rearing of species strictly associated with young and meristematic tissues. Rearing was also indirectly handled in a few others studies (Courtin et al 2000;Schwoebel and Beiderbeck 2000;Gondim and de Moraes 2003;Skare et al 2003;Ansaloni and Perring 2004;Skoracka and Kuczyński 2004;Witt 2004;Britto et al 2008), resulting in successful multiplication of eriophyoids dedicated to various subsequent biological investigations.…”

“…Wax secretion by adults and immatures has been recorded for Retracrus johnstoni Keifer (Gondim and de Moraes 2003). Frost (1997) showed that changes in the rate of wax production by grass-feeding A. hystrix had genetic and environmental components.…”