A new locality for the rare Guerreran Centipede Snake, Tantilla coronadoi Hartweg, 1944 (Squamata, Colubridae), with comments on morphological variation

We record the third known specimen of Tantilla coronadoi Hartweg, 1944 from Guerrero, Mexico. Our new record extends this species’ distribution by 90 km and to a new Mexican biogeographic province (Balsas Basin). The morphological similarity between this and the two previously known specimens supports the validity of the taxon, and otherwise points to the possible presence of an undescribed taxon on the coast of Guerrero. Additional fieldwork yielding a larger series of this and other infrequently encountered species may enable a better understanding of their distribution, natural history, ecology, and conservation.

Diversity and Genetic Structure of Dioon holmgrenii (Cycadales: Zamiaceae) in the Mexican Pacific Coast Biogeographic Province: Implications for Conservation

Dioon holmgrenii De Luca, Sabato et Vázq.Torres is an endangered species; it is endemic and its distribution is restricted to the biogeographic province of the Mexican Pacific Coast. The aim of this work was to determine the diversity and genetic structure of nine populations. The genetic diversity parameters and Wright’s F statistics were determined with six microsatellite loci. The genetic structure was determined by using the Structure software and by a discriminant analysis. The genetic diversity of the populations was high. The proportion of polymorphic loci was 0.89, the observed heterogeneity was higher (Ho = 0.62 to 0.98) than expected (He = 0.48 to 0.78), and the fixation index was negative (IF = −0.091 to −0.601). Heterozygous deficiency (FIT = 0.071) was found at the species level and heterozygotes excess (FIS = −0.287) at the population level. The genetic differentiation between populations was high (FST = 0.287), with the number of migrants less than one. Three groups of populations were differentiated, and the variation within populations, between populations, and between groups was: 65.5, 26.3, and 8.2%, respectively. Multiple factors explain the high genetic diversity, while the genetic structure is due to geographic barriers. Community reserves are urgent in at least one most diverse population of each group.

Rumohra ponceana (Polypodiales: Dryopteridaceae): a new species from Pampean biogeographic province in Argentina

The fern Rumohra ponceana sp. nov., a narrow endemic of the Austral Pampean district, Pampean biogeographic province in Argentina, is described and illustrated. The species inhabits the Tandilia and Ventania Systems, where it grows in sunny rock crevices. The new species differs from the widespread R. adiantiformis (sensu lato) by the reduced size of all parts of the sporophyte and conspicuous capitate glandular hairs at the margins of petiole and rhizome scales. Also, there are significant differences in the architecture of the laminae, the colour and size of the spores and the ornamentation of the perispore, which is folded in R. ponceana and projects in irregular tubercles throughout its surface.

Taxonomic notes on genus Floridotarsonemus (Acari: Tarsonemidae) with a description of two new species from West Bengal, India and keys to the world species

Two new species of Floridotarsonemus Attiah, 1970 (Acari: Heterostigmatina: Tarsonemidae), F. kukri Karmakar & Mondal sp. nov. and F. kanthali Karmakar & Mondal sp. nov. are described based on the specimens collected from Rhododendron indicum (Ericaceae), Cinchona officinalis (Rubiaceae) and Artocarpus heterophyllus (Moraceae) in Central Himalayan biogeographic province located in Darjeeling and Kalimpong district and Nadia district in the new alluvial zone of West Bengal, India. This registers the first record of Floridotarsonemus from the Indo-Malyan biogeographic realm. A note on the generic diagnosis of Floridotarsonemus and keys to differentiate the species of world Floridotarsaonemus are provided.

New records of lichens and lichenicolous fungi from Murmansk Region, Russia

As a contribution to the lichen flora of the Murmansk Region, eight taxa of lichens and lichenicolous fungi collected from the biogeographic province Kuusamo, are reported for the first time, including two species new to Russia: Roselliniella nephromatis and Scytinium aquale. Arthonia granitophila is new to European Russia, and Sclerophora amabilis – for North European Russia. Comments on habitats, substrates, key anatomical features and distribution of new records are provided.

Research on helminths from Mexican amphibians: gaps, trends, and biases

We present a taxonomic, spatial, and thematic overview of the current state of knowledge on helminth parasites of Mexican amphibians. Sixty-six host species have been studied so far, representing 17.5% of the amphibian species distributed in Mexico. A total of 139 nominal species of helminths – 68 platyhelminths, 62 nematodes, three acanthocephalans, three annelids (hirudineans), and three arthropods (pentastomids) – have been recorded parasitizing these hosts. Most taxa found in larval stages have not been identified at the species level. The gastrointestinal nematode Aplectana itzocanensis exhibits the broadest host range, while the bladder fluke Gorgoderina attenuata and A. itzocanensis show the widest geographic distribution. Our analysis of helminthological studies evidenced gaps and biases on research efforts that have been devoted to relatively few host species, regions, and approaches. Most helminthological records come from two species, the cane toad Rhinella marina and the Montezuma's frog Lithobates montezumae, and most studies have focused on describing the helminth fauna of a host species in a particular location or on the description of new helminth species. The highest proportion of records corresponds to the Veracruzan biogeographic province, and helminth richness is significantly correlated with host richness and with total amphibian richness by biogeographic province. Only three provinces (Yucatan Peninsula, Pacific Lowlands, and Baja Californian) have positive, yet still low helminth species discovery effort. Based on our findings, we recommend pursuing research approaches unexplored in Mexico and we provide guidelines to improve research on helminths parasitizing amphibians.

The first register of the weed fern Pteris cretica var. laeta (Pteridaceae) in central Argentina

Pteris cretica L. var. laeta is recorded for the first time in the Comechingones biogeographic province in central Argentina. This is the first record of P. cretica in central Argentina, and P. cretica var. laeta for the country. Until now Pteris cretica has only been known to occur, in America, in North America (Florida), Central America and South America in Neotropical biomes from Peru, Chile, Brazil, Paraguay, Uruguay and northern Argentina as established in the Yungas biogeographic province, and as ruderal in Buenos Aires. An updated description is provided, along with pictures, differences with P. cretica var. cretica, and characteristic of the novel habitat of the species.