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1.
Ecol Evol ; 14(9): e70274, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39267691

RESUMEN

Birds time their life cycle events to favourable windows in environmental conditions. In tropical environments, where photoperiod variation is small, birds show high variability in the timing of life cycle stages, yet these species have been severely underrepresented in phenology research. Here, we investigated temporal patterns in bird life cycles and resource availability in two sites in tropical Africa: Weppa (Nigeria, 7° N) and Elat (Cameroon, 3° N). In these sites we captured common bulbuls (Pycnonotus barbatus), a widespread generalist, and recorded breeding and moult over a 12-month period. Simultaneously, we surveyed fruiting tree and arthropod abundance. Our aim was to quantify seasonal patterns in moult and breeding in bulbuls at both sites, and link them to fluctuations in local fruit and arthropod abundance and precipitation. Moult was more seasonal than breeding in both sites, and seasonality of both life cycle events was stronger in Nigeria than Cameroon. The peak timing for moult was 1.5 months earlier in Nigeria than Cameroon. Seasonal variation in abundance of fruiting trees and arthropods was different between sites, as were the associations with breeding and moulting. In Nigeria, we found a positive association between moult and arthropod abundance, and a negative one with fruiting tree abundance. In contrast, in Cameroon moult was associated with higher precipitation, while breeding occurred at times with higher fruit abundance. Our results provide evidence that, even in similar habitats separated by four degrees in latitude, seasonal patterns across three trophic levels are variable. Understanding links between environmental conditions and life cycle events can reveal potential vulnerabilities of tropical species, and guide conservation efforts.

2.
Zootaxa ; 5188(2): 133-144, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37044789

RESUMEN

The genus Macroscirtus belongs to the subfamily Mecopodinae with five recognized species distributed in central-west tropical Africa. All species are known from very few localities. The species are reviewed and, in addition, a new species from Cameroon is described. Macroscirtus kekeunoui sp. nov. is characterized by the tegmina not reaching the penultimate abdominal segment; hind femura with mottled brown external face, ventral and internal face completely pale yellow; male subgenital plate elongated horizontally, indentation edge straight. Species descriptions of the genus are documented and a key to the species is also provided.


Asunto(s)
Ortópteros , Masculino , Animales , Distribución Animal
3.
Zootaxa ; 4915(1): zootaxa.4915.1.6, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33756586

RESUMEN

The specimens studied were collected with sweep net and pitfall in the forests, agro-forests, herbaceous fallows, and crop fields of 14 localities in the southern part of Cameroon, from August 2015 to February 2018. The results show that Heteracris hannai sp. nov. and Heteracris lecoqi sp. nov. differ from previously known species of the same genus by the pattern of coloration and the details or shape of the phallic complex. H. lecoqi sp. nov. is characterized by light brownish body; male cercus with flattened, downcurved and obtuse apex; lophus strongly curved; interlophal space with V shape; apodeme of cingulum bow, convergent, with V-shape; valve of cingulum in lateral view longer than apical valve of penis; ramus in ventral view joined. H. hannai sp. nov. is distinct to other species by brown to grey body; male cercus with apex rounded, curved inside; lophus curved; interlophal space with U-shape; apodeme of cingulum thick, slightly parallel, with U shape; valve of cingulum in lateral view hardly longer than apical valve of penis; ramus in ventral view opened. The characteristics of H. guineensis are closer to H. hannai sp. nov. than to H. lecoqi sp. nov. H. lecoqi sp. nov. was collected only in the fallows while H. hannai sp. nov. was collected in the forests, agro-forests, fallows, and crop fields. Compared to H. guineensis, both new species are scarce in the natural vegetation and their distribution area is limited to two and four localities respectively for H. lecoqi sp. nov. and H. hannai sp. nov. All these three grasshopper's species were recorded as accidental species in all types of vegetation.


Asunto(s)
Saltamontes , Ortópteros , Distribución Animal , Animales , Camerún , Masculino
4.
Zootaxa ; 4763(1): zootaxa.4763.1.5, 2020 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-33056879

RESUMEN

Gryllotalpa weisei Simeu-Noutchom Kekeunou sp. nov. was collected only in Tombel in the South-West region of Cameroon, during a survey conducted from March 2016 to March 2018 in the West, South-West and Centre regions of Cameroon. This species is close to Gryllotalpa microptera, collected for the first time in Cameroon during these investigations, only in the West region. G. weisei is different from G. microptera due to the hind wings that are vestigial; average fore wings length of 5.85±0.56 mm in male and 5.34±0.45 mm in female, not reaching the fifth abdominal segment; anal end of fore wings slightly concave; a stridulatory file with 54±8.02 teeth (47-71) in average, fairly spaced, with an average of 30±5.06 teeth per millimeter; hind tibia bearing 11 spines; internal process of ectophallus quite short. G. weisei abounds in mixed crop fields, followed by cocoa agro-forests; it is scarce in grassy fallows and in forest undergrowth. G. microptera was present in all types of vegetations in Bafoussam, Babeté and Bangoulap in the West region where it has been abundant in mixed crop fields, grass-fallow and coffee agro-forest but rare in forest undergrowth.


Asunto(s)
Ortópteros , Animales , Camerún , Femenino , Bosques , Masculino , Encuestas y Cuestionarios
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