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The black amaranth (Amaranthus quitensis Kunth) is traditionally cultivated in the Ecuadorian highlands, where it has great social, cultural and food importance for the native population, and locally it is called ataco or sangorache. Currently, there are no data on the diversity and conservation status in which the ataco landraces are found. We have evaluated the phenotypic diversity of black amaranth landraces collected at two different times (1981-1986 and 2014-2015) in three representative Andean provinces for this crop (Imbabura, Tungurahua and Cañar). Thirty agro-morphological descriptors were used, 11 quantitative and 19 qualitative. Most of the quantitative traits showed high levels of variation, especially grain yield per plant. The qualitative traits showed less diversity, although the characters related to the plant pigmentation and the shape and attitude of the inflorescence were significantly discriminating between accessions from different provinces. Few significant differences were detected between both collects, so the farmers seem to be carrying out adequate on-farm conservation of the ataco germplasm. The agro-morphological information obtained in this study may be useful for enhancing the use of this plant genetic resource in future amaranth breeding programs, as well as for effectively managing the black amaranth collection from Germplasm Bank of the Ecuadorian National Institute for Agricultural Research (INIAP).

Pineapple mealybug wilt has been reported as one of the most important diseases affecting pineapple crops worldwide. This study aimed to determine the prevalence of mealybugs associated with two agroclimatic zones of pineapple production in the department of Valle del Cauca, Colombia. The survey was conducted in the upper (Dagua, Restrepo, La Cumbre and Vijes) and lower (Buga and Palmira) land zones. A total of 75 MD2 pineapple plots in different development growth stages were evaluated. The mealybugs were recorded mainly in the upper land zone, with a prevalence of 32 %. Concerning the plots growth stages, the highest prevalence was observed in second-cycle plots (13.3 %), followed by third-cycle ones, including abandoned plots (9.3 %), and first-cycle plots (6.7 %), which were associated with the use of pesticides. Dysmicoccus brevipes was the only mealybug species (Pseudococcidae) found on pineapples in the study area.

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During a study carried out to determine the prevalence of mealybugs in pineapple (Ananas comosus) orchards conducted in the department of Valle del Cauca, Colombia, the parasitoid wasp Hambletonia pseudococcina Compere, 1936 (Hymenoptera: Encyrtidae) and the predatory fly Pseudiastata sp. (Diptera: Drosophilidae) were found in association with the pineapple mealybug Dysmicoccus brevipes (Cockerell, 1893) (Hemiptera: Pseudococcidae). These two natural enemies are briefly diagnosed and illustrated. This is the first record of the genus Pseudiastata in Colombia.

A total of 281 species of scale insects (Hemiptera: Coccomorpha) have been recorded in Colombia, South America. New information on Colombian scale insect diversity is presented based on the morphological examination of slide-mounted specimens preserved in museums and newly collected material during field collecting surveys in the Atlantic and Pacific coasts (including Valle del Cauca) of Colombia. Specimens were prepared for microscopy and identified using a morphological approach. Eight species are recorded for the first time in Colombia: Phalacrococcus howertoni Hodges & Hodgson, 2010 (Coccidae); Aspidiella hartii (Cockerell, 1895), Diaspis bromeliae (Kerner, 1778), Lepidosaphes tokionis (Kuwana, 1902), Pseudoparlatoria chiapensis Wolff, 2001 (Diaspididae); Comstockiella sabalis (Comstock, 1883) (Halimococcidae); Lecanodiaspis prosopidis (Maskell, 1895) (Lecanodiaspididae) and Phenacoccus tucumanus Granara de Willink, 1983 (Pseudococcidae). Taxonomic keys for scale species known from Colombia are provided for those genera which are newly recorded for the country. Additionally, new host records were found for 35 species previously recorded for Colombia: Pseudococcidae (11 spp.), Coccidae (11 spp.), Diaspididae (7 spp.), Aclerdidae (1 sp.), Eriococcidae (1 sp.), Monophlebidae (1 sp.), Ortheziidae (1 sp.), Putoidae (1 sp.) and Rhizoecidae (1 sp.).

The guava cottony scale, Capulinia linarosae Kondo & Gullan (Hemiptera: Eriococcidae), is an important pest of guava, Psidium guajava L. (Myrtaceae) in northern Colombia and Venezuela. A species of Metaphycus (Hymenoptera: Encyrtidae) is the only known primary parasitoid associated with this insect pest. The parasitoid is herein described as M. marensis Chirinos & Kondo, sp. nov., based on morphological characteristics of the adult female and male. Biological studies on adult longevity, fecundity, host preference, and sex ratio were conducted. The maximum longevity of the female and the male were 8.0 and 6.5 days, respectively, when fed with diluted honey. On average, a fed mated female laid approximately 40 eggs. Adult females of M. marensis were shown to prefer to parasitize 11- to 15-day-old adult females of C. linarosae and do not parasitize first-instar nymphs of the host eriococcid. The female-to-male sex ratio of the parasitoid was 2.24: 1. When ovipositing females of M. marensis were given only small-sized individuals (second-instar nymphs) of C. linarosae, generally the resulting progeny was a single male wasp. This parasitoid species has arrhenotokous reproduction and is a facultative gregarious parasitoid. These results show a short adult longevity, as well as a relatively low fecundity of the female compared with studies conducted on other Metaphycus species. This study provides essential baseline information for future biological control programmes for C. linarosae.

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