A historical perspective on the use and production of species of Dactylopius (Hemipetera: Dactylopiidae) and Opuntia (Cactaceae: Opuntioidae), information on their origin, diversity and distribution in Mexico are reviewed, and aspects of their conservation are discussed. The use and exploitation of both genera are part of Mexican cultures since prehistory. Opuntia species were among the main components of human diet during preagricultural times. Cochineal was used and probably cultivated at least from the Tenth century. During the colonial period, cochineal generated significant benefits to the Spaniard colonizers and Mexico was the world's first producer of insects and dyes until the mid Nineteenth century. Currently, Mexico is the main producer of Opuntia cladodes and prickly pear, but cochineal cultivation is marginal and only maintained in traditional indigenous systems. Mexico is one of the main areas of diversity of Opuntia, having 83-104 out of nearly 200 species worldwide. More than 50 species are used mainly as food, fodder and medicine and 20 species are cultivated with different degrees of domestication. The genus Dactylopius includes nine species, with five of them naturally occurring in Mexico. Only D. coccus has been cultivated and domesticated but other wild species have been used throughout history. Arid and semiarid areas of Mexico are among the most important reservoirs of biological diversity for both genera, particularly for D. coccus. Specific measures for protection of such biodiversity and generic resources are required. Strategies for in situ conservation combined with re-established use and cochineal production may enhance conservation policies.

Phylogenetic analyses, from polymerase chain reaction (PCR)-amplified 12S rRNA and 18S rRNA gene sequences from cochineal insects of the genus Dactylopius present in Mexico, showed that D. ceylonicus, D. confusus, and D. opuntiae are closely related. D. coccus constitutes a separate clade, and D. tomentosus is the most distantly related. Bacterial 16S rRNA sequences from all the Dactylopius species sampled showed a common β-proteobacteria, related to Azoarcus, also found in eggs and in bacteriocytes in D. coccus. We propose the name "Candidatus Dactylopiibacterium carminicum" for this endosymbiont. Other bacterial sequences recovered from the samples were close to those from soil or plant associated bacteria, like Massilia, Herbaspirillum, Acinetobacter, Mesorhizobium, and Sphingomonas, suggesting a possible horizontal transmission from Cactaceae plant sap to Dactylopius spp. during feeding. This is the first molecular analysis of Dactylopius species and of their associated bacteria.

The aim of this work was to characterize the mucilage extracted from six species of Opuntia. The species studied were as follows: O. atropes, O. tomentosa, O. hyptiacantha, O. streptacantha y O. joconostle and O. ficus‐indica. The first step was to find the best extraction conditions to obtain an unaltered chemical structure of mucilage. The mucilages were characterized using high‐performance liquid chromatography and Fourier transform infrared spectroscopy techniques. The optimal conditions employed to obtain the mucilage were: ratio of cladodes : ethanol solution at 50% of 1:1 (w/v), temperature of 22C and precipitation of mucilage with a solution of ethanol 96%, at a ratio of 1:4 (v/v). Mucilage from all species studied had a high content of soluble dietary fiber, ranging from 51.79 to 67.51%. In decreasing order, sugars found in the mucilages were: L‐arabinose (26.83–35.36%), D‐galactose (21.59–45.48%), D‐xylose (12.23–17.05%), uronic acids (5.59–13.91%), D‐glucose (5.18–16.21%) and L‐rhamnose (1.41–5.40%). Practical Applications This research presents an optimization method for the extraction of mucilage five wild species of cactus based on temperature and time of extraction and solvent ratio: sample used. Mucilages were characterized chemically and by chromatographic and Fourier transform infrared spectroscopy techniques and were compared with the species mucilage Opuntia ficus‐indica, the species most commercially studied. The mucilage obtained can be used for commercial purposes as additives in the food industry.

The distribution pattern of species of the genus Dactylopius Costa in Mexico was analyzed in relation to the distribution of their host plants (subfamily Opuntioideae) to evaluate the speci icity of the insect-host association. The distribution of Dactylopius currently recognized is narrower than that of its hosts and probably is not representative. Therefore, a broader distribution of the Dactylopius species in correspondence with those of their hosts was hypothesized. Insects and their hosts were collected and georeferenced in 14 states of Mexico from 2005 to 2007. The distribution areas, maps, and habitat characteristics of Dactylopius, Opuntia sensu stricto, Nopalea and Cylindropuntia were determined on the basis of ield collections and examination of museum collections. This information was complemented with information from the exhaustive examination of microscope slides from a local insect collection, plants from local herbaria, and literature reviews. The current distribution of the genus Dactylopius and its hosts included 22 and 25 states of Mexico, respectively, and Dactylopius had a continuous distribution according to its hosts, broader than recognized hitherto. The new georeferenced records of the ive Mexican Dactylopius species are reported. Insects with morphological characteristics of D. confusus combined with those of D. salmianus were identi ied, as well as insects with characteristics of D. opuntiae combined with those of D. salmianus. These records suggest that the number of local Dactylopius species could be higher than previously thought or that possible new processes of hybridization between native and introduced species may be occurring.

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