Genus Proceratium Research Articles

Contribution to the Knowledge of the Genus Proceratium Roger (Hymenoptera: Formicidae: Proceratiinae) in the New World

The genus Proceratium Roger comprises rare ants that are irregularly distributed in tropical and temperate regions of the world. Despite this global distribution, these ants are rarely collected, likely due to their cryptobiotic lifestyle. In the New World, the genus comprises 22 known species distributed from Southern Canada to the South of Brazil, and in some Caribbean islands. The taxonomy of the genus Proceratium is here updated for South America. We describe P. amazonicum sp. nov, from Rondônia state and provide distribution data for P. brasiliense, P. convexipes, and P. silaceum. We also present, for the first time, high-resolution images of the P. colombicum type and P. ecuadoriense, and provide a new record of P. micrommatum from Peru, and comment about its morphological variation and distribution. A key for the workers of the P. micrommatum clade is also provided. The species we describe belongs to P. micrommatum clade and represents the second species recorded from Brazil after 60 years, since only P. brasiliense was known previously in the country.

Mirmecofauna asociada a cafetales bajo sombra en Quipile, Cundinamarca, Colombia

La abundancia y variedad de microhábitats en los cultivos de café bajo sombra favorecen las poblaciones de hormigas. En cuatro fincas de la vereda Guadalupe alto del municipio de Quipile, Cundinamarca (Colombia) se determinaron la diversidad, la composición y los gremios de hormigas asociadas con el cultivo de café (Coffea arábiga) bajo sombra de Inga sp., Tabebuia rosea, Musa sp. y Citrus sp. Los muestreos se realizaron utilizando trampas de ‘caída y captura manual’ en épocas seca y de lluvia. En total, se registraron 82 morfoespecies distribuidas en 30 géneros y nueve subfamilias. Las eficiencias de muestreo variaron entre 78 y 82% con los estimadores CHAO2 e ICE; además, se encontró una baja similitud (< 60%) entre las fincas y entre los estratos suelo y tronco de árbol. Se identificaron especies exclusivas en las fincas como Heteroponera microps, Heteroponera inca, Odontomachus erytrocephalus y se registran por primera vez para Cundinamarca el género Proceratium y la especie Neoponera chyseri que incrementa la gran riqueza de especies de hormigas conocidas. Por otro lado, se encontró un total de nueve gremios presentes en todas las fincas del estudio y fueron reportados género como Azteca, Crematogaster, Linephitema, Pheidole y Solenopsis catalogados como potenciales controladores biológicos, lo que evidencia una forma de equilibrios ecosistémicos benéficos para el café bajo sombra en la zona.

Systematics of the ant genus Proceratium Roger (Hymenoptera, Formicidae, Proceratiinae) in China - with descriptions of three new species based on micro-CT enhanced next-generation-morphology.

The genus Proceratium Roger, 1863 contains cryptic, subterranean ants that are seldom sampled and rare in natural history collections. Furthermore, most Proceratium specimens are extremely hairy and, due to their enlarged and curved gaster, often mounted suboptimally. As a consequence, the poorly observable physical characteristics of the material and its scarcity result in a rather challenging alpha taxonomy of this group. In this study, the taxonomy of the Chinese Proceratium fauna is reviewed and updated by combining examinations of traditional light microscopy with x-ray microtomography (micro-CT). Based on micro-CT scans of seven out of eight species, virtual 3D surface models were generated that permit in-depth comparative analyses of specimen morphology in order to overcome the difficulties to examine physical material of Proceratium. Eight Chinese species are recognized, of which three are newly described: Proceratium bruelheidei Staab, Xu & Hita Garcia, sp. n. and P. kepingmai sp. n. belong to the P. itoi clade and have been collected in the subtropical forests of southeast China, whereas P. shohei sp. n. belongs to the P. stictum clade and it is only known from a tropical forest of Yunnan Province. Proceratium nujiangense Xu, 2006 syn. n. is proposed as a junior synonym of P. zhaoi Xu, 2000. These taxonomic acts raise the number of known Chinese Proceratium species to eight. In order to integrate the new species into the existing taxonomic system and to facilitate identifications, an illustrated key to the worker caste of all Chinese species is provided, supplemented by species accounts with high-resolution montage images and still images of volume renderings of 3D models based on micro-CT. Moreover, cybertype datasets are provided for the new species, as well as digital datasets for the remaining species that include the raw micro-CT scan data, 3D surface models, 3D rotation videos, and all light photography and micro-CT still images. These datasets are available online (Dryad, Staab et al. 2018, http://dx.doi.org/10.5061/dryad.h6j0g4p).

Revision of the ant genus Proceratium Roger (Hymenoptera, Proceratiinae) in Fiji

The Fiji archipelago harbours a surprisingly diverse and endemic ant fauna, despite its isolated and remote location in the South Pacific. The ant genus Proceratium is present on Fiji with three endemic species, of which Proceratium oceanicum De Andrade, 2003 and Proceratium relictum Mann, 1921 were previously known. In this study we describe the third species: Proceratium vinaka sp. n. All three species are members of the widespread and species-rich Proceratium silaceum clade. In order to integrate the new species into the current taxonomic system, we present an illustrated identification key to the worker caste of the three Fijian species. In addition, we provide a detailed description of Proceratium vinaka, as well as species accounts for the other two species, which include diagnoses, taxonomic discussions, specimen photographs, and a distribution map.

Taxonomy of the ant genus Proceratium Roger (Hymenoptera, Formicidae) in the Afrotropical region with a revision of the P. arnoldi clade and description of four new species

The taxonomy of the genus Proceratium Roger is updated for the Afrotropical region. We give an overview of the genus in the region, provide an illustrated identification key to the three clades (Proceratium arnoldi, Proceratium stictum and Proceratium toschii clades) and revise the Proceratium arnoldi clade. Four new species from the Proceratium arnoldi clade are described as new: Proceratium sokoke sp. n. from Kenya, Proceratium carri sp. n. from Mozambique, and Proceratium nilo sp. n. and Proceratium sali sp. n. from Tanzania. In order to integrate the new species into the existing taxonomic system we present an illustrated identification key to distinguish the seven Afrotropical species of the Proceratium arnoldi clade. In addition, we provide accounts for all members of the Proceratium arnoldi clade including detailed descriptions, diagnoses, taxonomic discussions, distribution data and high quality montage images.

A Description of the Male of Proceratium Croceum Emery, with Remarks.

Although the genus Proceratium was erected by Roger in 1863, the few species in this genus are known only from the worker and female phases. This has been due probably to the following reasons: either that myrmecologists have neglected to describe the males which they have collected, or they have not been fortunate enough to find the males associated with the females or workers, or they have failed to collect the males at all.