Petra Sánchez-Nava

Larval stages of trematodes in gastropods from Lake Chicnahuapan, State of Mexico, Mexico

During the period from January to December (2007), 1,095 freshwater molluscs of four species were captured (Lymnaea stagnalis, Stagnicola elodes, Physella cubensis and Physa acuta) in Lake Chicnahuapan, State of Mexico, Mexico. Two hundred seventy-two (24.84% prevalence) of these molluscs were parasitised by 11 trematode species (from which two were not identified at the species level) having six cercariae species and five metacercariae species represented in five families. The cercariae Telorchis corti (Plagiorchiidae) and the metacercariae Cotylurus cornutus (Strigeidae) were the species with the highest prevalence among the examined snails. The highest percentage of infection was observed in L. stagnalis (27.45% of prevalence, n = 572) and P. cubensis (23.96%, n = 455). Twenty-one of the examined snails had multiple infections with up to three trematode species.

HELMINTH PARASITES OF THE TROPICAL GAR, ATRACTOSTEUS TROPICUS GILL, FROM TABASCO, MEXICO

A total of 8 helminth species were recorded in an examination of 43 tropical gar, Atractosteus tropicus Gill, collected at the Pantanos de Centla Biosphere Reserve, Tabasco, Mexico. The parasite species included 1 adult trematode, 3 metacercariae, 1 cestode, 1 adult nematode, and 2 nematode larvae. Six of these 8 species were rare, with low prevalence (<17%) and abundance (<1.0 helminths per examined fish). The larvae of Contracaecum sp. were the most abundant in the sample, constituting 60% of the total helminths (64% prevalence, 3.8 ± 5.2 abundance), followed by the cestode Proteocephalus singularis, constituting 18% of the worms (30.5% prevalence, 1.1 ± 3.0 abundance). Species richness, individual parasite abundance, and diversity were low in the infracommunities. The recording of 3 specialist species in the tropical gar confirms that the helminth fauna of gar has an appreciable degree of specificity. This study indicates the importance of ecological determinants of richness in helminth communities of the tropical gar.

Corky-root symptoms for coffee in central Veracruz are linked to the root-knot nematode Meloidogyne paranaensis, a new report for Mexico

The coffee corky-root disease associated with root-knot nematode infection is a major concern for coffee production in Mexico, particularly in the Veracruz State where substantial losses from Coffea arabica plantations are reported annually due to this disease. Previous studies based on perineal patterns of Meloidogyne females identified M. incognita as the species responsible for coffee corky root disease in this state. Populations of Meloidogyne were collected from coffee plants with corky root symptoms and from intercropped banana plants, when present, in eight sites distributed through the major coffee growing region of Veracruz State. These populations were characterized by multiplex PCR using sequence-characterized amplified region (SCAR) markers for the three major coffee Meloidogyne species in Latin America: M. exigua, M. incognita and M. paranaensis. M. paranaensis was the only species present on all eight coffee samples and is reported here for the first time in Mexico. Consequently, the coffee industry in Mexico should focus more attention to this very destructive root-knot nematode, particularly at the prophylactic level to avoid its dissemination via nursery seedlings. Additionally, M. paranaensis was found in the five samples of intercropped Musa AAA and AA plants suggesting that this crop is a good host and a potentially important way of dispersal of this very pathogenic root-knot nematode since banana suckers are frequently used by growers for plantation renovations. Additionally, M. incognita was detected on Musa AAA and AA plants in three of the five studied sites with intercropped banana but never on the coffee plants even those sampled nearby banana plants.

Rediscovered Population of Mexican Plateau Spotted Whiptail Lizard, Aspidoscelis septemvittata (Teiidae), from México, D.F.

ABSTRACT. Multiple surveys carried out by herpetologists in México, D.F., during the 1980s failed to find specimens of Aspidoscelis septemvitatta (Squamata: Teiidae). However, 10 specimens were recently collected to the east of México, D.F., inside a protected area, Sierra de Santa Catarina. The Sierra de Santa Catarina has been heavily modified by human activity and habitation. Morphological and natural history information about the specimens are presented, as well as notes on locality.