José Antonio Guerrero

Operational criteria for genetically defined species: analysis of the diversification of the small fruit-eating bats, Dermanura (Phyllostomidae: Stenodermatinae)

Species diversity and species limits of the small fruit-eating bats, genus Dermanura (Phyllostomidae: Stenodermatinae) were examined. Estimates of species diversity based on classical morphological criteria (current taxonomy) were compared to diversity estimates based on monophyly and cytochrome-b sequence divergence. The most recent taxonomic list included nine species, whereas the genetic based list contained 11: anderseni, azteca, bogotensis, cinerea, glauca, gnoma, phaeotis, rava, rosenbergi, tolteca, and watsoni, of which three (bogotensis Andersen, rava Miller, and rosenbergi Thomas) have been considered synonyms of cinerea, glauca, phaeotis, and tolteca by previous authors. In addition, we consider incomitata to be a synonym of watsoni. Phylogenetic analyses of mtDNA sequences resolved the interrelationships among taxa and prompted us to re-evaluate some morphological characters that support the distinction of all the recognized taxa, therefore providing a robust estimate of species status. A phylogenetic tree revealed a geographic component to the diversification of Dermanura, including a historical connection between western Andean and Middle American biota. In South America, no species has been recorded from both sides of the Andes Mountains, and at least one clade (glauca, gnoma, and bogotensis) is restricted to the eastern versant of the Andes. Using genetic data (monophyly and genetic distance) to identify species we were able to produce testable genealogical and biogeographic hypotheses to facilitate further studies.

Aggression and tolerance by dominant males of Artibeus jamaicensis: strategies to maximize fitness in harem groups

Abstract Strategies of males in harem-forming mammals may change depending on 2 variables, female group size and consequent ability of the harem male to monopolize copulations, and the relative costs and benefits of tolerating other males. We studied harems of 4–20 females associated with a dominant male in small groups of Artibeus jamaicensis (<14 females), and with dominant and subordinate males in large groups (>14 females). Dominant males displayed defensive behavior toward satellite males when they intruded into the roosting site. Small groups received the highest number of visits by satellite males, and dominant males did not display total defense of females. During the breeding season, females roosted in highly compacted clusters and dominant males were more active in their defensive behavior. Subordinate males were generally tolerated in harem groups and their presence reduced the number of adult male visits. Some young in large harem groups were sired by subordinate males, resulting in a genetic benefit for both dominant and subordinate males. Dominant males had the highest fitness in the large harem groups by sharing paternity with related subordinate males and by rejecting unrelated intruders.

TAXONOMIC STATUS OF ARTIBEUS JAMAICENSIS TRIOMYLUS INFERRED FROM MOLECULAR AND MORPHOMETRIC DATA

Abstract The taxonomic status of Artibeus jamaicensis triomylus was evaluated by mitochondrial cytochrome-b sequences, as well as cranial morphometric comparisons with 4 other subspecies of the A. jamaicensis complex and 5 species of large Artibeus. Phylogenetic analyses showed that 2 monophyletic groups exist within A. jamaicensis complex, separated by a sequence divergence of 3.6%. One clade grouped samples of A. j. triomylus from western Mexico, and the other contained samples of A. j. yucatanicus, A. j. richardsoni, A. j. paulus, and A. j. jamaicensis from the Gulf of Mexico, Central America, and the Caribbean. Additionally, multivariate analyses revealed a significant divergence in quantitative cranial characters between A. j. triomylus and non-triomylus specimens. These results, in conjunction with morphological data previously reported, suggest that A. j. triomylus represents a distinct and monophyletic lineage, consequently deserving recognition at the species rank.

Relationship between the abundance of the Endangered volcano rabbit Romerolagus diazi and vegetation structure in the Sierra Chichinautzin mountain range, Mexico

The volcano rabbit Romerolagus diazi is endemic to the mountains of central Mexico, where its habitat has been gradually destroyed to make way for agriculture, ranching and logging, and by forest fires. The volcano rabbit is categorized as Endangered on the IUCN Red List. We evaluated the relationship between the abundance of the volcano rabbit and vegetation structure at a small scale (0.25 ha). Using a general linear model we generated a set of 21 predictive models and proposed the best model as a habitat quality index. Our results suggest that greater height and cover of bunchgrasses and the presence of a shrub layer offer the volcano rabbit the best refuge from predators. The habitat quality index and the limited available habitat documented in our survey indicate that the populations of volcano rabbits in the study area are more threatened than previously thought. As R. diazi is a habitat specialist it does not have the option of moving to another habitat type.

Cranial differentiation of fruit-eating bats (genus Artibeus) based on size-standardized data

Size-standardized craniometric variation was investigated among species of the genus Artibeus. Eleven extant and one extinct species were examined using geometric and linear morphometric analyses to evaluate morphological differences among species. Based on 19 landmarks located in the ventral side of the cranium, 29 size-standardized linear measurements were calculated and used for statistical multivariate analyses. Discriminant Function Analysis showed major interspecific differences in shape between A. anthonyi and A. concolor with respect to the remaining extant species of Artibeus. These two species are described as morphologically unique morphotypes with a broader rostrum, enlarged squamosal region, and wider basicranium. Specifically, a broader premaxilla is the character that better discriminates A. anthonyi from all other species, whereas a broader squamosal region (particularly the deep mandibular fossa, and elongated squamosal) and wider braincase are the main characters differentiating A. concolor. All other species of the genus overlap to varying extents in their morphology showing high shape similarities. The least variant shape features include the pterygoid fossa, the glenoid (mandibular) fossa, the maxillae, and the occipital region; these regions in all cases contribute to mechanical aspects of jaw function and bite. The fact that the least variant aspects of skull shape all involve feeding is consistent with the hypothesis that selection has favored a specific diet-associated morphology rather than divergence or character displacement in Artibeus.

A NEW SPIRURID (NEMATODA) PARASITE FROM MORMOOPID BATS IN MEXICO

Abstract: A new nematode species, Spirura mexicana n. sp., is described from specimens recovered from the esophageal mucosa of the Parnells mustached bat Pteronotus parnellii, Davys naked-backed bat Pteronotus davyi, Wagners mustached bat Pteronotus personatus, and the ghost-faced bat Mormoops megalophylla in the State of Morelos, Mexico. This nematode is characterized by having a relatively short prostoma, 5–6 pairs of caudal papillae, and a smooth distal end of the tail in females. This is the first species of Spirura described from bats in the New World.

TAXONOMIC STATUS OF ARTIBEUS ANTHONYI (CHIROPTERA: PHYLLOSTOMIDAE), A FOSSIL BAT FROM CUBA

Abstract The subgenus Artibeus includes 8 species of frugivorous bats of widespread neotropical distribution. The only fossil species, Artibeus anthonyi, was described from deposits of the Cuban Quaternary, and its taxonomic status has been debated in the literature. Based on exceptionally well-preserved new fossil material, an emended diagnosis and a detailed description of the cranium of A. anthonyi are presented. In addition, we used multivariate analyses to explore the morphometric differentiation between A. anthonyi and the extant species of the subgenus Artibeus. A. anthonyi shows the greatest morphological divergence compared with extant Artibeus species.

Pterygodermatites (Pterygodermatites) mexicana n. sp. (Nematoda: Rictulariidae), a parasite of Balantiopteryx plicata (Chiroptera) in Mexico

A new species of nematode, Pterygodermatites (Pterygodermatites) mexicana n. sp., is described based on specimens recovered from the intestine of the gray sac-winged bat, Balantiopteryx plicata (Chiroptera, Emballonuridae), from the Biosphere Reserve “Sierra de Huautla” in the state of Morelos, Mexico. This is the second species in the genus described from bats in the New World, since most of the rictaluriids reported in these hosts belong to the closely related genus Rictularia Froelich, 1802. However, members of Rictularia possess only a single oesophageal tooth at the base of the buccal capsule, whereas in the current nematodes three conspicuous oesophageal teeth are present. They are therefore included in Pterygodermatites Wedl, 1861. The new species is characterized by the presence of 23 small denticles on the periphery of the buccal capsule and by the presence of 40 and 66 pairs of cuticular processes in males and females, respectively. Additionally, males possess 3–4 ventral precloacal fan-like processes, and the cuticular processes of females are divided into 40 pairs of comb-like and 26 pairs of spine-like processes; the vulva opens on the level of approximately pair 40. The dorsally directed stoma and the 40 prevulvar cuticular processes makes it difficult to place the species in any of the subgenera present in the New World, yet characters correspond with the diagnosis of Pterygodermatites (Pterygodermatites) in the Mediterranean region and North Africa.

Configuration of the volcano rabbit (Romerolagus diazi) landscape in the Ajusco-Chichinautzin Mountain Range

Endemic to the central mountains of the Trans-Mexican Volcanic Belt, the volcano rabbit (Romerolagus diazi), known locally as the zacatuche, is a threatened species at risk of extinction. In the Ajusco-Chichinautzin Mountain Range, the Pelado and Tlaloc volcanoes are core distribution areas for this species; however, suitable habitat within these areas is patchy. We analyzed the habitat of this species at the landscape level, taking into account biotic, abiotic, and anthropogenic factors. We used geographic information systems for the habitat analysis and a linear mixedeffects model to identify the habitat patches available, analyze them in the FRAGSTATS program, and calculate their landscape metrics. To identify the habitat of the volcano rabbit, we used its relative abundance index in the context of land use and vegetation, elevation, slope, road and highway density, and distance to human settlements. The analyses indicated that the relative abundance index of this species decreases with increasing proximity to human settlements and with increasing road and highway density. At the landscape level, there are 957 patches of habitat available to the species, covering 75.44 km2. Most of the patches are 2,500 m2 in area and regular in shape (square); however, because they are small patches it is possible that they will disappear. The largest patches are located on the Pelado and Tlaloc volcanoes, and coincide with the core distribution areas of the volcano rabbit described in the literature.

New records of flowering plants in Morelos state, Mexico

Nine new records of flowering plants are reported for Morelos state, Mexico. Most of the species occur at the Biological Corridor Chichinautzin and the Biosphere Reserve Sierra of Huautla, located at north and south of Morelos state, respectively. A brief diagnosis, phenology, notes and illustrations are included. These records are the outcome of floristic studies carried out by the authors in both natural reserves.