Biota colombiana

20-31

Authors: Esteban Terneus Jácome, Berenice Vallejo, Mateo Gómez de la Torre

We evaluated the impact of climate change on the structure and floral composition of the aquatic plants occurring in five Andean lakes (3900 m a. s. l.) at the foot of the Chiles Volcano. We obtained field information using transects and depth quadrants to evaluate richness and cover vegetation patterns, whereas physical chemistry of water was evaluated using electronic measuring equipment in situ. Part of the information from the same lakes 17 years ago was used as a basis for comparison. Were recorded fifteen species of aquatic plants, with evidence of a reduction in the populations of Isoetes sp., Crassula venezuelensis and Elatine ecuadoriensis. Apparently, Lilaeopsis schaffneriana and Juncus stipulatus were replaced by Lachemilla nivalis and a Poaceae of the genus Agrostis as a colonizer. The abiotic characteristics of the lakes show changing trends in pH and conductivity of the waters, turning them more neutral than acidic. This leads to conditions that may allow for the establishment of species other than those of historical records, increasing the general variety, implying the possibility that climate change effects are not necessarily negative in this situation. However, there is evidence of damage to the natural aquatic ecosystem, through the loss or replacement of hydrophilic for halophile plants. This potential transformation process of the natural environment jeopardizes the ecological functioning of the aquatic ecosystems in the area.

46-58

Authors: Zuleyma Mosquera Murillo, Sandra Patricia Sánchez Vazquez

We present a preliminary report on the richness and distribution of aquatic Diptera in the department of Chocó, from 490 specimens (larvae and pupae) kept in the Chocó Limnological Collection (CLCH-Insec), corresponding to 18 municipalities (between 5 and 3202 m a.s.l.), 46 water streams of different order and 14 lentic ecosystems of the Atrato, San Juan and Baudó Rivers basins. There are 12 families and 30 genera, of which 4 families and 16 genera are recorded for the first time for Chocó. Chironomidae is the most abundant and most widely distributed family, while Dixidae and Sciomyzidae are the families with lowest abundance and distribution. The highest taxonomic richness is recorded for the families Culicidae and Ceratopogonidae, with five genera each. Macrophytes are the substrate with the greatest specific richness. The largest taxonomic record is found in the Atrato River basin, with 11 families and 24 genera. These results show the enormous diversity of aquatic Diptera in the department of Chocó and the need to develop new research that will broaden their taxonomic and ecological knowledge in the region.

76-92

Authors: Carlos A. Aya-Cuero, Federico Mosquera-Guerra, Diego A. Esquivel, Daniel Brooks, Fernando Trujillo

We describe the diversity of medium and large mammals from an area in the Colombian Orinoco River basin. For three years we systematically used camera traps at 72 sampling stations and walked forest and savanna transects to determine the diversity of medium and large mammals. Relative abundance was documented for 29 native and 2 feral mammals from a sampling effort of 1789 camera-days and 469.5 km walked. Thirty-one species of mammals (9 orders, 19 families) were recorded. Threatened species recorded included the giant armadillo (Priodontes maximus), lowland tapir (Tapirus terrestris), white-lipped peccary (Tayassu pecari), and giant anteater (Myrmecophaga tridactyla). The most abundant species were the collared peccary (Pecari tajacu) and the common opossum (Didelphis marsupialis). We recorded rare species, including the bush dog (Speothos venaticus) and the Llano semi-endemic long-nosed armadillo (Dasypus sabanicola). The species documented face diverse pressures, including development, hunting for subsistence, and competition with invasive species and livestock. Our results suggest that the surveyed areas are important for the conservation of mammals in the eastern plains of Colombia.

105-119

Authors: Julieth Stella Cárdenas Hincapie, Diana Alexandra Delgadillo Méndez

The anuran collection of the Museo de La Salle is one of the oldest in Colombia, with 2059 specimens collected since 1917. Its age represents a challenge for a thorough quantification of its status, considering that it may not necessarily fit current quality standards. Therefore, we implemented a methodology to evaluate the status of the collection in terms of health, data completeness, taxonomic representativeness, taxonomic identification and geographical coverage. The collection harbors 13 families, with Craugastoridae as the best represented, with 44 species and 517 specimens. The department with the largest number of specimens was Cundinamarca, with 363 records of 52 species. Most specimens are in optimal condition of conservation and preservation. The results of this research enabled the solution of problems in the collection and it could be useful for other collections.

128-133

Authors: Edison Gabriel Mejía Valenzuela

Leucism is a congenital hypopigmentary disorder that has been described in several species of wild mammals, as an abnormal and unusual condition. The first record of Dasyprocta fuliginosa with leucism is presented and the possible causes of this condition are discussed.