Alcides Sánchez-Monge

An updated list of the plants associated with plant-parasitic Aphelenchoides (Nematoda: Aphelenchoididae) and its implications for plant-parasitism within this genus.

Few Aphelenchoides spp. are facultative plant-parasites (foliar and bulb nematodes); three of them are well known in agricultural systems, namely Aphelenchoides besseyi, A. fragariae and A. ritzemabosi. Ten other plant-parasitic species, A. arachidis, A. bicaudatus, A. blastophthorus, A. dalianensis, A. ensete, A. nechaleos, A. paranechaleos, A. saprophilus, A. sphaerocephalus and A. subtenuis, have been reported from a limited number of plant species. We compiled a new database of the associated plants for these thirteen species, a comprehensive list that includes 1104 reports from 126 botanical families. A. besseyi, A. fragariae and A. ritzemabosi represent 94% of the reports, circa 83% and 16% of the total reports correspond to flowering plants and ferns, respectively, with three records on conifers and two from other botanical groups also listed. Most plant-parasitic Aphelenchoides show a remarkably broad diversity of associated plants. Most species appear to have no specific plant hosts (i.e. are generalists). The broad host ranges of these species and absence of more intimate interactions with the associated plants highlights the primitive mode of parasitism in Aphelenchoides species, making them potentially interesting in the study of the evolution of plant parasitism. Even though the compiled list of associated plants is long, it probably only represents a fraction of the potential range. The complete compilation has been uploaded to http://nematodes.myspecies.info/.

mtCOI successfully diagnoses the four main plant-parasitic Aphelenchoides species (Nematoda: Aphelenchoididae) and supports a multiple origin of plant-parasitism in this paraphyletic genus

Composed mostly of fungivorous species, the genus Aphelenchoides also comprises 14 plant-parasitic species. The most common and devastating, A. besseyi, A. fragariae, A. ritzemabosi and A. subtenuis have been reported on more than 900 plant species. The combination of low inter-specific and high intra-specific morphological variability makes morphology-based identification extremely difficult within this genus, and has led to molecular tools being employed to ensure accurate diagnoses. rDNA markers are widely used for the identification of nematodes while the Cytochrome Oxidase I gene (COI) remains relatively unexplored despite its role as the standard barcode for almost all animal groups. To explore its suitability as a diagnostic tool, we studied a fragment of the mtCOI region of the four main plant-parasitic Aphelenchoides within a phylogenetic framework. We generated 69 mtCOI and 123 rDNA sequences of diverse Aphelenchoides taxa; 67 belong to the main plant-parasitic species including the first mtCOI sequence of A. fragariae and the first mtCOI and 28S sequences of A. subtenuis. mtCOI had a similar success rate for PCR amplification. Phylogenetic trees based on the three studied markers are largely in agreement with one another, validating their use for Aphelenchoides diagnosis; additionally, we were able to locate several misidentified sequences of plant-parasitic Aphelenchoides in existing databases. The concatenated analysis from the three markers resulted in a more robust insight into the phylogeny and evolution of Aphelenchoides, revealing that plant-parasitism has evolved independently at least three times within this genus, presumably from fungal-feeding ancestors.

A Contribution to Thrips-Plant Associations Records (Insecta: Thysanoptera) in Costa Rica and Central America

ABSTRACT Thrips are small, cosmopolitan insects directly or indirectly associated with plants. Records of these associations in the neotropics add greatly to better understanding of Thysanoptera, not the least because some thrips species are economically important in agriculture and amenity plantings. In this paper we report new plant associations of Franklinothrips vespiformis (Crawford), Gastrothrips sp. Hood, Haplothrips gowdeyi Franklin, Leptothrips astutus Johansen, Leptothrips obesus Johansen, Liothrips spp. Uzel, Torvothrips martinezi Johansen, Arorathrips mexicanus Crawford, Caliothrips fasciapennis (Hinds), Caliothrips nanus (Hood), Caliothrips punctipennis (Hood), Echinothrips caribbeanus Hood, Echinothrips selaginellae Mound, Frankliniella cephalica Crawford, Frankliniella standleyana Hood, Hoodothripiella ignacio Retana-Salazar, Microcephalothrips abdominalis (Crawford) and Retanathrips silvestris (Hood). Some records of the presence of thrips species are new for Costa Rica and Central America.

New Records of Aphid-Plant Associations (Hemiptera: Aphididae) from Eastern Costa Rica

ABSTRACT Aphids cause damage to numerous crops and ornamentals. Most of them are relatively host specific, but some species are polyphagous and feed on several different hosts. In this paper we present new records for Aphis gossypii Glover, Aphis spiraecola Patch, Myzus ornatus Laing, Myzus persicae Sulzer, Hysteroneura setariae Thomas and Schizaphis rotundiventris Signoret, on several hosts belonging to a wide variety of plant families.

Three-dimensional modelling and printing as tools to enhance education and research in Nematology

Three-dimensional (3D) modelling has an increasing number of applications in different fields as it eases the understanding and enhances the representation of complex 3D structures and objects (Murakawa et al., 2006). Within biological sciences, several tools and techniques have been used to build 3D representations of organisms, e.g., serial images acquired from transmission electron microscopy (TEM), confocal laser scanning microscopy (CSLM), scanning electron microscopy (SEM), digital single-lens reflex camera (DSLR), μ-CT or light microscopy (LM) reconstructions (Hall, 1995; Bumbarger et al., 2006, 2009; Beutel et al., 2008; Ragsdale et al., 2008, 2009, 2011; Apolonio Silva De Oliveira et al., 2012; Wipfler et al., 2012; Handschuh et al., 2013; Nguyen et al., 2014). However, these techniques require multiple focal plane images, different objective angles, or rotation of the specimen. Furthermore, these techniques are not only time-consuming but often difficult for nematodes given their minute size and high transparency. Here we propose a relatively simple time-saving method using Autodesk® Maya®, a software widely used in animation and industrial design (Derakhshani, 2012). With this method a 3D model can be created based only on the combination of LM and SEM images; LM serves as a reference for the modelling and the position of internal structures and SEM images are incorporated as a reference for general body shape and surface details. The presented method uses the default tools of the

Ultrastructural Morphology of Larva II of Taeniothrips inconsequens (Terebrantia: Thripidae)

Abstract Thysanoptera comprises both economically neutral species and economically important pests of crops. The immature stages of many pest species are not well known and, ironically, those are the most harmful stages for crops. Taeniothrips inconsequens (Uzel) has been reported on at least 35 different host plant species and it is found almost worldwide, but the knowledge of this species is still incomplete. Herein we present SEM images of the larva II of T. inconsequens with comments and remarks on specific features for the accurate identification of this species.

NEW RECORDS OF THRIPS (THYSANOPTERA) FROM CENTRAL AMERICA WITH COMMENTS ON SPECIFIC CHARACTERS

The increase in Thysanoptera research has led to the description of new species, especially in the Neotropic region (Mound 2002). Similarly, new location records for species considered endemic are common in the current literature, as in the case of Ameranathrips herediae Mound & Marullo and Neohydatothrips hadrosetae Mound & Marullo both described for Costa Rica and found recently in Cuba (Gonzalez & Suris 2005; Gonzalez & Castillo 2009). Neohydatothrips hadrosetae was described in Costa Rica from a single specimen in poor condition. A similar case is that of Ethirothrips firmus Hood, which was known only from 5 specimens collected in Brazil and was recently collected in the State of Nayarit in Mexico (ValenzuelaGarcia et al. 2011). With the development of new technologies to study the geographical distribution of species occurrence, the acquisition of new records is important in order to establish new distribution points of various species. These types of data become an essential tool for modern ecology because they lead to an accurate portrayal of species’ distribution and behavior and thereby allow us to predict new locations as potential sites for colonization (Broennimann & Guisan 2008). New localities in Central America for 2 known species are reported in this paper, and comments on variations of their morphological characters are included.