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1.
Mol Phylogenet Evol ; 191: 107977, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38008369

RESUMO

A highly endemic ant fauna is found in the arid regions of southern Africa, including species in the genus Ocymyrmex. This genus of ants has higher species richness in the western arid regions of southern Africa compared to tropical and subtropical parts of the continent. The processes that have produced these patterns of diversity and distribution of arid adapted ants in southern Africa have never been investigated. The diversification of many other taxa in the region has been associated with past climate fluctuations that occurred during the Miocene epoch. In this study, the nature and timing of historical processes that may have led to the diversification within Ocymyrmex were assessed. We hypothesized that past climate oscillations, characterized by long periods of aridification, have driven the current distribution of Ocymyrmex species that resulted in the highest species richness of the genus in the Deserts & xeric shrublands biome in southern Africa. Ninety-four Ocymyrmex worker specimens from Botswana, Kenya, Namibia, South Africa, Tanzania and Zimbabwe, representing 21 currently described species and six morphospecies, were included in a phylogenomic analysis. Phylogenies for the genus, based on next generation sequencing data from ultraconserved elements, were inferred using Maximum Likelihood, and a dating analysis was performed using secondary age estimates as calibration points. A distribution database of Ocymyrmex records was used to assign species ranges, which were then coded according to major biomes in southern Africa and used as input for biogeographical analysis. We explored the phylogenomic relationships of Ocymyrmex and analysed these within a biogeographical and paleoclimatic framework to disentangle the potential processes responsible for diversification in this group. Dating analyses estimated that the crown age of Ocymyrmex dates to the Oligocene, around 32 Ma. Diversification within this group occurred between the mid-Miocene (∼12.5 Ma) and Pleistocene (∼2 Ma). Our biogeographic analyses suggest that Ocymyrmex species originated in the south-western region of southern Africa, which is now part of the Deserts & xeric shrublands biome and diversified into eastern subtropical areas during the Pliocene. Paleoclimatic changes resulting in increased aridity during the Miocene likely drove the diversification of the genus Ocymyrmex. It is most likely that the diversification of grasslands, because of historical climate change, facilitated the diversification of these ants to the eastern parts of southern Africa when open grasslands replaced forests during the early Miocene.


Assuntos
Formigas , Animais , Filogenia , Formigas/genética , Ecossistema , Florestas , África Austral
2.
Naturwissenschaften ; 111(4): 41, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080026

RESUMO

Ant-following behavior is a common phenomenon in birds of Neotropical and Afrotropical rainforests but yet little is known from Central Africa. We here report on the phenomenon in lowland rainforest in Cameroon, quantifying the strength of the interaction of different ant-following bird species with driver ants and test the hypothesis that higher levels of specialization in ant-following behavior are associated with dominance or aggression-dependent plumage and other morphological traits. Flock size varied between 1 and 11 individuals with a mean size of 5.34 ± 2.68 (mean ± SD) individuals occurring at the same time. The maximum number of species present during one raid observed was ten, whereas the minimum number was four with an overall species richness of 6.89 ± 2.1 species. The 21 attending bird species strongly varied in the degree of ant-following behavior. In an interspecific comparison, plumage traits such as the presence of a colored crown, eyespots, and bare skin around the eye, in combination with metatarsus length and weight, were significantly correlated with ant-following behavior. These results suggest that-in size and identity of species-ant-following bird assemblages in Central Africa are similar to those reported from East Africa. They also suggest that ant following favors the selection of traits that signal dominance in interactions between individuals struggling for valuable food resources in the forest understory.


Assuntos
Formigas , Comportamento Animal , Aves , Animais , Formigas/fisiologia , Aves/fisiologia , Camarões , Comportamento Animal/fisiologia , Plumas/fisiologia , Plumas/anatomia & histologia , Floresta Úmida
3.
Mol Phylogenet Evol ; 162: 107178, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33892098

RESUMO

Rhipicephalus are a species-diverse genus of ticks, mainly distributed in the Afrotropics with some species in the Palearctic and Oriental regions. Current taxonomic consensus comprise nine informal species groups/lineages based on immature morphology. This work integrates biogeographic, ecological and molecular lines of evidence to better understand Rhipicephalus evolution. Phylogenetic analysis based on four genes (12S, 16S, 28S-D2 and COI) recovered five distinct clades with nine descendant clades that are generally congruent with current taxonomy, with some exceptions. Historical biogeography is inferred from molecular divergence times, ancestral distribution areas, host-use and climate niches of four phylogenetically significant bioclimatic variables (isothermality, annual, seasonal and diurnal temperature range). Novel hosts enabled host-linked dispersal events into new environments, and ticks exploited new hosts through nested predator-prey connections in food webs. Diversification was further induced by climate niche partitioning along gradients in temperature range during off-host periods. Ancestral climate niche estimates corroborated dispersal events by indicating hypothetical ancestors moved into environments with different annual and seasonal temperature ranges along latitudinal gradients. Host size for immature and adult life stages was important for dispersal and subsequent diversification rates. Clades that utilise large, mobile hosts (ungulates and carnivores) early in development have wider geographic ranges but slower diversification rates, and those utilising small, less mobile hosts (rodents, lagomorphs and afroinsectivores) early in development have smaller ranges but higher diversification rates. These findings suggest diversification is driven by a complex set of factors linked to both host-associations (host size, ranges and mobility) and climate niche partitioning along annual and seasonal temperature range gradients that vary with latitude. Moreover, competitive interactions can reinforce these processes and drive speciation. Off-host periods facilitate adaptive radiation by enabling host switches along nested predator-prey connections in food webs, but at the cost of environmental exposure that partitions niches among dispersing progenitors, disrupting geneflow and driving diversification. As such, the evolution and ecological niches of Rhipicephalus are characterised by trade-offs between on- and off-host periods, and these trade-offs interact with nested predator-prey connections in food webs, host-use at different life stages, as well as gradients in annual and seasonal temperature ranges to drive adaptive radiation and speciation.


Assuntos
Cadeia Alimentar , Especiação Genética , Especificidade de Hospedeiro , Filogenia , Rhipicephalus/classificação , Rhipicephalus/genética , Temperatura , Animais , Ecossistema , Feminino , Masculino
4.
Am J Bot ; 107(7): 1004-1020, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32643810

RESUMO

PREMISE: Despite the fast pace of exploration of the patterns and processes influencing Neotropical plant hyperdiversity, the taxa explored are mostly from large groups that are widely distributed, morphologically diverse, or economically important. Vochysiaceae is an example of an undersampled taxon, providing an excellent system for investigating Neotropical biogeography. We present a phylogenomics-based hypothesis of species relationships in Vochysiaceae to investigate its evolutionary history through space and time. METHODS: We inferred a phylogeny for 122 species from Vochysiaceae and seven other families of Myrtales. Fossils from four myrtalean families were used to estimate the divergence times within Vochysiaceae. Historical biogeography was estimated using ancestral range probabilities and stochastic mapping. RESULTS: Monophyly of all genera was supported except for Qualea, which was split by Ruizterania into two clades. Vochysiaceae originated ~100 mya, splitting into an Afrotropical and a Neotropical lineage ~50 mya, and its ancestral range is in the area currently occupied by the Cerrado. CONCLUSIONS: The most recent common ancestor of Vochysiaceae + Myrtaceae had a West Gondwanan distribution, supporting a South American + African ancestral range of Vochysiaceae. On a global scale, geographic range reduction was the principal biogeographic event. At a finer scale, initial range reduction was also important and the Cerrado region was the most ancestral area with multiple colonization events to the Amazon, Central America, and the Atlantic Forest. Colonization events occurred from open areas to forest vegetation, an unusual finding regarding the evolution of plants in the Neotropics.


Assuntos
Myrtales , Teorema de Bayes , América Central , Filogenia , Filogeografia
5.
BMC Evol Biol ; 19(1): 166, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31434566

RESUMO

BACKGROUND: The Old World insectivorous bat genus Rhinolophus is highly speciose. Over the last 15 years, the number of its recognized species has grown from 77 to 106, but knowledge of their interrelationships has not kept pace. Species limits and phylogenetic relationships of this morphologically conservative group remain problematic due both to poor sampling across the Afrotropics and to repeated instances of mitochondrial-nuclear discordance. Recent intensive surveys in East Africa and neighboring regions, coupled with parallel studies by others in West Africa and in Southern Africa, offer a new basis for understanding its evolutionary history. RESULTS: We investigated phylogenetic relationships and intraspecific genetic variation in the Afro-Palearctic clade of Rhinolophidae using broad sampling. We sequenced mitochondrial cytochrome-b (1140 bp) and four independent and informative nuclear introns (2611 bp) for 213 individuals and incorporated sequence data from 210 additional individuals on GenBank that together represent 24 of the 33 currently recognized Afrotropical Rhinolophus species. We addressed the widespread occurrence of mito-nuclear discordance in Rhinolophus by inferring concatenated and species tree phylogenies using only the nuclear data. Well resolved mitochondrial, concatenated nuclear, and species trees revealed phylogenetic relationships and population structure of the Afrotropical species and species groups. CONCLUSIONS: Multiple well-supported and deeply divergent lineages were resolved in each of the six African Rhinolophus species groups analyzed, suggesting as many as 12 undescribed cryptic species; these include several instances of sympatry among close relatives. Coalescent lineage delimitation offered support for new undescribed lineages in four of the six African groups in this study. On the other hand, two to five currently recognized species may be invalid based on combined mitochondrial and/or nuclear phylogenetic analyses. Validation of these cryptic lineages as species and formal relegation of current names to synonymy will require integrative taxonomic assessments involving morphology, ecology, acoustics, distribution, and behavior. The resulting phylogenetic framework offers a powerful basis for addressing questions regarding their ecology and evolution.


Assuntos
Quirópteros/classificação , Quirópteros/genética , Filogenia , África , Animais , Núcleo Celular/genética , Citocromos b/genética , DNA Mitocondrial/genética , Íntrons , Simpatria
6.
BMC Ecol ; 19(1): 45, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676006

RESUMO

BACKGROUND: Vector-borne diseases are among the leading causes of morbidity and mortality in humans and animals. In the Afrotropical region, some are transmitted by Culicoides, such as Akabane, bluetongue, epizootic haemorrhagic fever and African horse sickness viruses. Bluetongue virus infection has an enormous impact on ruminant production, due to its high morbidity and mortality rates. METHODS: A nationwide Culicoides trapping campaign was organized at the end of the 2012 rainy season in Senegal. A Maximum Entropy approach (MaxEnt), Boosted Regression Tree (BRT) method and Ecological Niche Factor Analysis (ENFA) were used to develop a predictive spatial model for the distribution of Culicoides, using bio-climatic variables, livestock densities and altitude. RESULTS: The altitude, maximum temperature of the warmest month, precipitation of the warmest quarter, mean temperature of the wettest quarter, temperature seasonality, precipitation of the wettest quarter and livestock density were among the most important factors to predict suitable habitats of Culicoides. Culicoides occurrences were, in most of the cases, positively correlated to precipitation variables and livestock densities; and negatively correlated to the altitude and temperature indices. The Niayes area and the Groundnut basin were the most suitable habitats predicted. CONCLUSION: We present ecological niche models for different Culicoides species, namely C. imicola, C. oxystoma, C. enderleini and C. miombo, potential vectors of bluetongue virus, on a nationwide scale in Senegal. Through our modelling approach, we were able to determine the effect of bioclimatic variables on Culicoides habitats and were able to generate maps for the occurrence of Culicoides species. This information will be helpful in developing risk maps for disease outbreaks.


Assuntos
Vírus Bluetongue , Ceratopogonidae , Animais , Ecossistema , Insetos Vetores , Senegal
7.
Mol Phylogenet Evol ; 127: 119-128, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29772349

RESUMO

We examined the colonization history and phylogeographic structure of the two endemic freshwater crab species (Potamonautes margaritarius and P. principe) inhabiting the volcanic islands of São Tomé and Príncipe, respectively, using mitochondrial and nuclear DNA sequence data. All samples were sequenced for the mtDNA COI locus and used in the phylogeographic analyses, while a single specimen per lineage was sequenced for the two remaining loci (16S rRNA and histone 3) and used in the phylogenetic reconstruction. Phylogenetic results reveal that P. principe diverged early within a clade of East/Southern African Potamonautes during the Miocene, while P. margaritarius diverged between the Late Eocene to Early Miocene. Furthermore, the two species are not sister taxa and are distantly related. These results corroborate previously hypothesised independent transoceanic dispersal events that resulted in the establishment of the endemic freshwater crab fauna of the two islands. Within P. margaritarius, we observed two reciprocally monophyletic clades on São Tomé Island. Clade one occurred in the southeast and southwest of the island, while clade two occurred in the northeast and the northwest; the divergence between the latter two clades was estimated to be of Pleistocene age. The two clades within P. margartarius are genetically highly structured and characterised by the absence of shared maternal haplotypes, suggesting possible speciation within P. margartarius. In contrast P. principe exhibits a shallow population genetic structure. Possible mechanisms of colonization and cladogenesis in the two freshwater crabs are discussed.


Assuntos
Evolução Biológica , Braquiúros/classificação , Água Doce , Ilhas , Filogeografia , Animais , Braquiúros/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Filogenia , RNA Ribossômico 16S/genética , São Tomé e Príncipe , Fatores de Tempo
8.
Ecol Lett ; 19(3): 308-17, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26807694

RESUMO

Declines in migratory species are a pressing concern worldwide, but the mechanisms underpinning these declines are not fully understood. We hypothesised that species with greater within-population variability in migratory movements and destinations, here termed 'migratory diversity', might be more resilient to environmental change. To test this, we related map-based metrics of migratory diversity to recent population trends for 340 European breeding birds. Species that occupy larger non-breeding ranges relative to breeding, a characteristic we term 'migratory dispersion', were less likely to be declining than those with more restricted non-breeding ranges. Species with partial migration strategies (i.e. overlapping breeding and non-breeding ranges) were also less likely to be declining than full migrants or full residents, an effect that was independent of migration distance. Recent rates of advancement in Europe-wide spring arrival date were greater for partial migrants than full migrants, suggesting that migratory diversity may also help facilitate species responses to climate change.


Assuntos
Distribuição Animal , Migração Animal , Aves/fisiologia , Animais , Mudança Climática , Europa (Continente) , Dinâmica Populacional , Estações do Ano
9.
Mol Phylogenet Evol ; 97: 233-241, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26724404

RESUMO

Afrotropical Acraeini butterflies provide a fascinating potential model system to contrast with the Neotropical Heliconiini, yet their phylogeny remains largely unexplored by molecular methods and their generic level nomenclature is still contentious. To test the potential of mitogenomes in a simultaneous analysis of the radiation, we sequenced the full mitochondrial genomes of 19 African species. Analyses show the potential of mitogenomic phylogeny reconstruction in this group. Inferred relationships are largely congruent with a previous multilocus study. We confirm a monophyletic Telchinia to include the Asiatic Pareba with a complicated paraphylum, traditional (sub)genus Acraea, toward the base. The results suggest that several proposed subgenera and some species groups within Telchinia are not monophyletic, while two other (sub)genera could possibly be combined. Telchinia was recovered without strong support as sister to the potentially interesting system of distasteful model butterflies known as Bematistes, a name that is suppressed in some treatments. Surprisingly, we find that this taxon has remarkably divergent mitogenomes and unexpected synapomorphic tRNA rearrangements. These gene order changes, combined with evidence for deviating dN/dS ratios and evidence for episodal diversifying selection, suggest that the ancestral Bematistes mitogenome has had a turbulent past. Our study adds genetic support for treating this clade as a distinct genus, while the alternative option, adopted by some authors, of Acraea being equivalent to Acraeini merely promotes redundancy. We pave the way for more detailed mitogenomic and multi-locus molecular analyses which can determine how many genera are needed (possibly at least six) to divide Acraeini into monophyletic groups that also facilitate communication about their biology.


Assuntos
Borboletas/genética , Genoma Mitocondrial/genética , Genômica , Filogenia , Animais , Borboletas/classificação , Ordem dos Genes/genética , RNA de Transferência/genética
10.
J Therm Biol ; 52: 58-66, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26267499

RESUMO

Seasonal trends in metabolic parameters are well established in avian populations from highly seasonal environments, however, seasonal trends in metabolism of birds from lower latitudes (and of Afrotropical birds in particular) are not well understood. We investigated seasonal trends in metabolism for a small (10-12g) Afrotropical bird, the Cape White-eye (Zosterops virens), using flow-through respirometry in two summers and two winters. There was no seasonal difference in body mass between consecutive seasons. The lower critical limit of thermoneutrality was lower in winter (23°C) than in summer (28°C), as expected for a small Afrotropical bird. In the first year of the study, mean whole animal basal metabolic rate (BMR) of Cape White-eyes was significantly lower in winter than in summer, while in the second year of the study this trend was reversed, and in the middle two seasons there was no significant difference in BMR. Differences in mean temperature and mean rainfall between seasons could not account for the seasonal trends in BMR. We conclude that seasonal trends in avian BMR may vary between years, within a population.


Assuntos
Metabolismo Basal/fisiologia , Passeriformes/fisiologia , Estações do Ano , Aclimatação , Animais , Peso Corporal/fisiologia , Meio Ambiente , Feminino , Geografia , Masculino , Troca Gasosa Pulmonar , Chuva , África do Sul , Perda Insensível de Água/fisiologia
11.
J Therm Biol ; 51: 119-25, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25965025

RESUMO

Seasonal variation in avian metabolic rate is well established in Holarctic and temperate species, while trends in Afrotropical species are relatively poorly understood. Furthermore, given the paucity of data on circannual rhythm in avian metabolism, it is not known whether seasonal measurements made in summer and winter correspond with annual peaks and troughs in avian metabolic rate. Thus, we investigated how mean body mass, resting metabolic rate (RMR) and evaporative water loss (EWL) of a small Afrotropical bird, the Cape white-eye (Zosterops virens), changed monthly over the course of a year at 20°C and 25°C. Mean body mass was 12.2±1.0g throughout the study period. However, both EWL and RMR varied monthly, and peaks and troughs in RMR occurred in March and October respectively, which did not correspond to peaks and troughs in mean monthly outdoor ambient temperatures. These results suggest that measuring RMR at the height of summer and winter may underestimate the flexibility of which birds are capable in terms of their metabolic rate. We encourage further studies on this topic, to establish whether the lag between environmental temperature and RMR is consistent in other species.


Assuntos
Metabolismo Basal , Passeriformes/metabolismo , Estações do Ano , Aclimatação , Animais , Temperatura , Água/metabolismo
12.
Zookeys ; 1203: 95-130, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38846746

RESUMO

Ctonoxylon is a strictly Afrotropical genus of bark beetles breeding under bark of rainforest trees and lianas. A taxonomic revision of the genus included a molecular phylogenetic analysis of ten species based on three gene fragments and was compared to a morphology-based tree topology for all 24 currently recognised species. Four species are described as new to science: Ctonoxylontorquatum, sp. nov., Ctonoxylontuberculatum, sp. nov., Ctonoxylonquadrispinum, sp. nov., all from Madagascar, and Ctonoxylonpilosum, sp. nov. from Cameroon. Ctonoxylonhirsutum Hagedorn, 1910, stat. rev. is resurrected from synonymy with C.flavescens Hagedorn, 1910, and C.atrum Browne, 1965 stat. rev. from its synonymy with C.methneri Eggers, 1922 (as C.hamatum Schedl, 1941). The following species have new synonymies suggested: Ctonoxylonfestivum Schedl, 1941 (= C.dentigerum Schedl, 1941, syn. nov.), C.methneri Eggers, 1922 (= C.hamatum Schedl, 1941, syn. nov., = C.griseum Schedl, 1941, syn. nov.), C.montanum Eggers, 1922 (= C.longipilum Eggers, 1935, syn. nov., = C.nodosum Eggers, 1940, syn. nov.), C.camerunum Hagedorn, 1910 (= C.conradti Schedl, 1939, syn. nov.), and C.spinifer Eggers, 1920 (= C.setifer Eggers, 1920, syn. nov.). New country records are noted for C.festivum (Tanzania), C.flavescens (Uganda), C.camerunum (Liberia), C.crenatum Hagedorn, 1910 (Democratic Republic of the Congo), C.spathifer Schedl, 1941 (Ghana), C.atrum (Cameroon), and C.spinifer (Madagascar), with patterns in distribution and colonisation of Madagascar discussed. An identification key with pictures of all species is provided.

13.
Ecol Evol ; 14(9): e70153, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39224163

RESUMO

The Afrotropics are experiencing some of the fastest urbanisation rates on the planet but the impact of city growth on their rich and unique biodiversity remains understudied, especially compared to natural baselines. Little is also known about how introduced species influence ß-diversity in these contexts, and how patterns coincide with native ranges of species. Here we investigated how tree assemblages of the endemic-rich Afrotropical island of São Tomé differed between urban, rural and natural zones. These were primarily characterised by urban greenspaces, shade plantations, and old-growth forests, respectively. Based on 81 transects, we assessed biodiversity metrics of endemic, native and introduced species. Tree abundance and species richness were highest in the natural zone, where the composition was most different from the urban zone. The tree community of the rural zone was the most uneven and had the least variation among transects, representing the lowest ß-diversity. The urban zone was dominated by introduced species (57.7%), while the natural zone hosted almost exclusively native species (93.3%), including many endemics (26.1%). The biogeographic realms that species originated from were particularly diverse in the urban zone, with few species from the Afrotropics. In contrast to native and endemic trees, introduced trees were clearly associated with urban and rural expansion, as they were much more abundant and species-rich in these zones than in the natural zone, facilitating biotic homogenisation. These findings highlight how urban and rural environments are affecting the native tree flora of São Tomé, and the need for conservation measures geared towards globally threatened and endemic tree species. Importantly, these require the protection of natural forests, despite the rising land demands for settlements and agriculture. Ultimately, such action to conserve endemic trees will contribute to global efforts to prevent further biodiversity declines.

14.
Zookeys ; 1202: 303-327, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836191

RESUMO

The revision of the flea beetle genus Argopistes Motschulsky, 1860 in Madagascar is provided. Six new species are described: Argopistesjanakmoravecorumsp. nov., A.laterosinuatussp. nov., and A.vadoni from the northern area; A.jenisisp. nov., A.keiserisp. nov., and A.seyrigisp. nov. from the central area. A new synonym of Argopistesbrunneus Weise, 1895 is established: A.sexguttatus Weise, 1895, syn. nov., since A.sexguttatus is shown to be a chromatic form of A.brunneus. A diagnostic key of the seven Malagasy Argopistes species is provided, with photographs of the habitus, median lobe of the aedeagus, and spermatheca. Finally, based on known occurrences, the current suitable areas for this flea beetle genus in Madagascar are estimated using Ecological Niche Modelling (ENM) techniques.

15.
J Exp Biol ; 216(Pt 20): 3811-7, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24068349

RESUMO

The capacity for nonshivering thermogenesis (NST) plays an important role during arousal from torpid states. Recent data on heterotherms inhabiting warmer regions, however, suggest that passive rewarming reduces the need of metabolic heat production during arousal significantly, leading to the question: to what extent do subtropical or tropical heterotherms depend on NST? The African lesser bushbaby, Galago moholi, enters torpid states as an emergency response only, but otherwise stays normothermic throughout the cold and dry winter season. In addition, this species shows unusual rewarming difficulties during arousal from torpor on cold days. We therefore examined the seasonal adjustments of the capacity for NST of naturally acclimatized G. moholi by stimulation with noradrenaline (NA) injection. Dissection of two adult female bushbabies revealed that G. moholi possesses brown adipose tissue, and NA treatment (0.5 mg kg(-1), s.c.) induced a significant elevation in oxygen consumption compared with control (saline) injection. However, the increase in oxygen consumption following injection of NA was not significantly different between winter and summer. Our results show that the ability to produce heat via NST seems to be available throughout the year and that G. moholi is able to change NST capacity within a very short time frame in response to cold spells. Together with results from studies on other (Afro-)tropical heterotherms, which also indicate low or even absent seasonal difference in NST capacity, this raises the question of whether the definition of NST needs to be refined for (Afro-)tropical mammals.


Assuntos
Galago/fisiologia , Termogênese/fisiologia , Aclimatação/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/fisiologia , África , Animais , Metabolismo Basal/efeitos dos fármacos , Metabolismo Basal/fisiologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Feminino , Masculino , Norepinefrina/administração & dosagem , Norepinefrina/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Estações do Ano , Temperatura Cutânea/efeitos dos fármacos , Temperatura Cutânea/fisiologia , Termogênese/efeitos dos fármacos
16.
Zookeys ; 1178: 39-59, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692914

RESUMO

A new species of the order Zoraptera, Zorotypuskomatsui Matsumura, Maruyama, Ntonifor & Beutel, sp. nov., is described from Cameroon. The female and male morphology of another species, Z.vinsoni, is re-described, and its new distribution in Madagascar is recorded. A particular focus is on the male postabdominal morphology. This is apparently a crucial body region in the very small order with an extreme variation of the genital apparatus but otherwise a very uniform morphology. The male of the newly described species shares rudimentary male genitalia and well-developed postabdominal projections with the distantly related Spermozorosimpolitus, apparently a result of parallel evolution. Whether males of Z.komatsui also perform external sperm transfer like S.impolitus remains to be shown. The collecting of the material used for this study suggests that the present knowledge of zorapteran species diversity of the Afrotropical region is very fragmentary.

17.
Folia Parasitol (Praha) ; 702023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37522654

RESUMO

The genus Coitocaecum Nicoll, 1915 is part of the most speciose digenean family, the Opecoelidae Ozaki, 1925, which is found globally in both freshwater and marine fishes. Fifteen opecoelid species have been reported from marine fishes in South Africa, yet only one species of Coitocaecum has been described from this region: Coitocaecum capense Bray, 1987. During an explorative study of the digeneans of the endemic, intertidal fish Clinus superciliosus (Linnaeus) from the Saldanha Bay area, Cape Town harbour, Hermanus, the Tsitsikamma section of the Garden Route National Park and Chintsa East in South Africa, a total of three distinct species of Coitocaecum were identified based on morphological and molecular (28S rDNA, ITS1-5.8S-ITS2 rDNA and COI mtDNA) data: the previously mentioned C. capense, Coitocaecum brayi sp. n. and a third, unnamed species. We provide the first molecular characterisation of species of Coitocaecum from South Africa, accompanied by detailed morphological descriptions. This study illustrates the importance of an integrated taxonomic approach, especially when studying species with similar morphology. These findings further emphasise the lack of information on the true diversity and molecular data for trematodes of marine fishes in South Africa, creating a great capacity for future explorative taxonomic studies and highlighting the use of intertidal areas for conducting such research.


Assuntos
Perciformes , Trematódeos , Animais , África do Sul , Filogenia , DNA Ribossômico/genética , Peixes
18.
Zookeys ; 1145: 181-189, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234695

RESUMO

Polyclada Chevrolat and Procalus Clark are flea beetle genera (Coleoptera, Chrysomelidae, Galerucinae, Alticini). Polyclada is endemic to the Afrotropical region, while Procalus has never been described outside of the Neotropical region. The new combination Procalusmaculipennis (Bryant, 1942), comb. nov. is proposed for Polycladamaculipennis Bryant, 1942. Its plausible type locality is Venezuela, and not Cameroon, as recorded on the labels of the type material, and hence the occurrence of P.maculipennis in Africa is questionable.

19.
Insects ; 14(8)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37623402

RESUMO

The Afrotropical hoverflies remain an understudied group of hoverflies. One of the reasons for the lack of studies on this group resides in the difficulties to delimit the species using the available identification keys. DNA barcoding has been found useful in such cases of taxonomical uncertainty. Here, we present a molecular study of hoverfly species from the eastern Free State of South Africa using the mitochondrial cytochrome-c oxidase subunit I gene (COI). The identification of 78 specimens was achieved through three analytical approaches: genetic distances analysis, species delimitation models and phylogenetic reconstructions. In this study, 15 nominal species from nine genera were recorded. Of these species, five had not been previously reported to occur in South Africa, namely, Betasyrphus inflaticornis Bezzi, 1915, Mesembrius strigilatus Bezzi, 1912, Eristalinus tabanoides Jaennicke, 1876, Eristalinus vicarians Bezzi, 1915 and Eristalinus fuscicornis Karsch, 1887. Intra- and interspecific variations were found and were congruent between neighbour-joining and maximum likelihood analyses, except for the genus Allograpta Osten Sacken, 1875, where identification seemed problematic, with a relatively high (1.56%) intraspecific LogDet distance observed in Allograpta nasuta Macquart, 1842. Within the 78 specimens analysed, the assembled species by automatic partitioning (ASAP) estimated the presence of 14-17 species, while the Poisson tree processes based on the MPTP and SPTP models estimated 15 and 16 species. The three models showed similar results (10 species) for the Eristalinae subfamily, while for the Syrphinae subfamily, 5 and 6 species were suggested through MPTP and SPTP, respectively. Our results highlight the necessity of using different species delimitation models in DNA barcoding for species diagnoses.

20.
Zookeys ; 1160: 89-108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37187461

RESUMO

A new species of freshwater crab, Potamonautesamatholesp. nov., is described from the Winterberg-Amathole mountain range in the Eastern Cape Province, South Africa. Morphologically, P.amathole Peer & Gouws, sp. nov. most closely resembles P.tuerkayi but can be distinguished by key morphological characters including the variation in the shape of the subterminal segment of gonopod 2 between both species. Genetically, P.amathole Peer & Gouws, sp. nov. is placed within the clade of small-bodied, mountain-dwelling crabs including P.parvispina, P.parvicorpus, P.brincki, P.tuerkayi, P.baziya, and P.depressus. The new species is found in slow-moving mountain streams and pools at high altitudes. The continued discovery and description of new freshwater crab species reinforces the need for ongoing research, especially in under-sampled regions.

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