Manoel G.C. Gondim

Can the red palm mite threaten the Amazon vegetation

The red palm mite Raoiella indica Hirst (Tenuipalpidae) was first reported in the New World in 2004, dispersing quickly and widely while adopting new plant species as hosts. Since then, it has caused severe damage in this region, especially to coconut (Cocos nucifera L.). It was first found in Brazil in 2009, in the northern Amazonian state of Roraima. In the present study, native and introduced plants were sampled between March 2010 and February 2011 in sites of the 15 Roraima municipalities, to estimate its distribution and the associated mite fauna. In addition, monthly samples were taken from a coconut plantation in Mucajaí throughout the same period, for an initial appraisal of the levels R. indica could reach. It was found in 10 municipalities, on 19 plant species of four families. Six species are reported for the first time as hosts. Among the associated predators, 89.1% were Phytoseiidae, most commonly Amblyseius largoensis (Muma), Iphiseiodes zuluagai Denmark & Muma and Euseius concordis (Chant). The highest densities of R. indica, 1.5 and 0.35 mites/cm2 of leaflet (approx total of 331 and 77 mites/leaflet), were reached respectively in March 2010 and February 2011. The highest density of phytoseiids on coconut (0.009 mites/cm2 or about 2 mites/leaflet) was reached in November 2010. The average densities of R. indica recorded for Roraima were comparable to those reported for countries in which the mite is reportedly economically damaging. The dispersal of R. indica through the Amazon forest may result in damage to cultivated and native palms, and plants of other families, if the projected increase in both the frequency and the severity of drought events occurs. Parts of the Amazon have undergone periods of low rainfall, a condition that appears to favour the biology of this mite. Its eventual arrival to northeastern Brazil may result in heavy economic and ecological losses.

A new deuterogynous eriophyid mite (Acari: Eriophyidae) with dimorphic males from Caesalpinia echinata (Caesalpiniaceae) from Brazil: description and biological observations

Abstract Aceria inusitata Britto and Navia n. sp. (Acari: Eriophyidae) is described from protogynes, deutogynes and two forms of males occurring under a “patches of webbing” from “pau-brasil,” Caesalpinia echinata L. (Caesalpiniaceae), leaves. This is the first example of a deuterogynous eriophyid mite in tropical regions with two forms of males, one resembling the protogyne and the other the deutogyne. In addition, biological observations are presented. Aberoptus cerostructor Flechtmann, is given a new generic assignment, Aceria cerostructor n. comb.

Compatibilidade reprodutiva de duas populações de Iphiseiodes zuluagai Denmark & Muma (Acari: Phytoseiidae)

The present work consisted of an evaluation of the reproductive compatibility between two populations of a predatory mite preliminarily identified as Iphiseiodes zuluagai Denmark & Muma, obtained from a commercial plantation of Citrus sinensis (L.) Osbeck. (Rutaceae) and from Syagrus romanzoffiana (Cham.) Glassman (Arecaceae) found in a forest area. The results of this study could indicate the possibility that the latter system could serve as a reservoir of I. zuluagai to the former. The colonies of I. zuluagai were maintained in a laboratory using the method described by Reis et al. (1988), at 25±1oC, 85±5% of R.H. and 12h light: 12h dark. The reproductive compatibility was evaluated through crosses and back-crosses between mites of each colony and observations on their fecundity during 10 days. The heterogamic crosses and the back-crosses resulted in fertile progeny in proportions comparable to homogamic crosses. These results indicate that both tested populations belong to the same species, which suggest a possible positive role of S. romanzoffiana as reservoir of I. zuluagai, from which the predator could eventually re-colonize patches of cultivated plants.

A new species of the genus Typhlodromips De Leon (Acari: Phytoseiidae) from the state of Bahia, Brazil.

ABSTRACT A new species of Phytoseiidae, Typhlodromips theobromae n. sp., is described from the leaves of cocoa, Theobroma cacao L. (Sterculiaceae), and mango, Mangifera indica L. (Anacardiaceae), from the State of Bahia, northeastern Brazil.

A new species of Proctolaelaps Berlese (Acari: Ascidae) from northeastern Brazil

Abstract Proctolaelaps bulbosus n. sp. (Acari: Ascidae) is described from adult females and males of a laboratory colony derived from a collection from Cocos nucifera L. (Arecaceae) in northeastern Brazil. This species is distinguished from other Proctolaelaps species by the absence of the setae z3 and R3, knobbed seta Z5 and long spermatodactyl.

Effect of relative humidity on the biology of the predatory mite Amblyseius largoensis (Acari: Phytoseiidae)

ABSTRACT Amblyseius largoensis Muma (Acari: Phytoseiidae) is a common predator in the humid tropics, where it has been found in association with Raoiella indica Hirst (Acari: Tenuipalpidae), an important coconut pest. The objective of this study was to assess the performance of A. largoensis from Recife, Pernambuco, northeast Brazil (Atlantic Forest biome), under different levels of relative humidity (RH). Also, to analyse the world-wide distribution of A. largoensis. This phytoseiid was evaluated at the following development RH levels (20%, 36%, 56%, 65%, 72%, 80%, 89%, and 95%) and on reproduction RH levels (66%, 83%, 91%, and 98%) at 27°C. Amblyseius largoensis failed to complete development at or below 72% RH. Maximum population increase of the predator (about 26-fold in one generation) occurred at 91% RH. Only 7% of the records of the distribution of A. largoensis were from hot arid areas. The results suggested, that while the Recife population of A. largoensis is well adapted to survive high RH conditions, its efficiency as a biological control agent might be limited in drier inland areas. Thus, populations of A. largoensis that occur in drier areas of the world should be evaluated as to their potential as biological control agents of R. indica.

New taxa of eriophyid mites (Acari: Eriophyidae) from fruit trees in northeastern Brazil

Abstract A new genus and a new species of Phyllocoptini associated with soursop, Annona muricata L. (Annonaceae), namely Shrekin graviolae n. gen. and n. sp., and a new species of Nothopodini associated with the West Indian cherry, Malpighia emarginata Sessé and Moc. (Malpighiaceae), namely Cosella decorata n. sp., are described from the State of Pernambuco, northeastern Brazil.