A new species, Hypoxis colliculata from Oaxaca and Chiapas, México is presented here. It belongs to the group with black seeds and is separated from the other species by the colliculate sculpturing of the seeds.

Phragmipedium warscewiczii is reported as new record for the Mexican orchid flora from material recently collected in Chiapas. The species is described from Mexican specimens and it is compared with P. exstaminodium, its closest ally. The Mexican locality is the…

During fieldwork in San Juan Teponaxtla, Oaxaca, 3 individuals of Aristolochia tricaudata Lemaire, a very rare species threatened with extinction, were observed with flowers and fruits. Although this species is present in many botanical gardens, fruits have never been observed.…

Two orchid species, both previously known from Central America, are reported for the Mexican flora: Oncidium poikilostalix and Telipogon helleri. The former species was previsouly known under the name Sigmatostalix poikilostalix, and the latter as Stellilabium helleri. The rediscovery of…

Here is described the first dinosaur evidence from Chiapas, and also the southernmost evidence of dinosaurs in Mexico. A small theropod tooth, identified as Richardoestesia isosceles, based on its shape and the presence of small denticles on the mesial and…

Acanthocereus chiapensis Bravo was described from plants collected in Chiapas, Mexico in March 1967. Field observations as well as detailed morphological and anatomical studies revealed that this entity rather belongs to genus Peniocereus. This taxonomic opinion was supported by the…

A lungworm of the genus Rhabdias (Nematoda: Rhabdiasidae) was recovered from Scinax staufferi (Anura: Hylidae) collected in Guadalupe Victoria Mapastepec, Chiapas, Mexico (15°28'28"N, 92°53'26"W, 102 m). Morphology of the nematode is briefly described and compared with other species of the…

Two species of Orchidaceae are recorded here for the first time in Mexico, namely Cryptarrhena guatemalensis and Domingoa gemma. Cryptarrhena guatemalensis is widespread in the Neotropics and can be distinguished from C. lunata, the only other species of the genus,…

This study analyzes data and information of the physical and chemical characteristics of water, and type of sediments of the continental shelf of the Gulf of Tehuantepec, Mexico. The changes of salinity, temperature, and dissolved oxygen fluctuate according to the…

After 22 years of the 1982 eruption of El Chichón volcano, we conducted a statistically based survey of the residents of the community of Chapultenango (10 km east of the volcano) to assess their perception of volcano hazards and risk.…