SOIL ORGANISMS

Soil BON Earthworm - A global initiative on earthworm distribution, traits, and spatiotemporal diversity patterns

Mon, 01 Apr 2024 00:00:00 +0200

Recent research on earthworms has shed light on their global distribution, with high alpha richness in temperate zones and high beta diversity in tropical areas. Climate and agricultural practices, notably plowing and conservation methods, were shown to strongly influence earthworm communities. However, data gaps persist in regions like North Australia, Asia, Russia, and Africa, limiting our understanding of earthworm distribution and their responses to global changes. Understanding changes within earthworm communities is crucial given their profound influence on ecosystem functions such as soil structure, nutrient dynamics, and plant growth. Classifying earthworms into functional groups remains complex, prompting the adoption of a trait-based approach for a more comprehensive classification, but there is no representative global data on earthworm traits. To address these knowledge gaps, the Soil BON Earthworm initiative aims at creating a global community of earthworm experts, standardizing sampling methods and databases, collecting time series data on earthworm communities, and modeling future earthworm distributions under different climate scenarios. The initiative aims to address key questions, such as the dynamic of earthworm communities over time and their response to environmental factors and anthropogenic influences, their impact on ecosystem functioning, and the redefinition of functional groups based on traits. The consortium invites researchers worldwide to contribute to this endeavor and encourages the resampling of study sites, to expand currently limited time series datasets. To facilitate data collection, standardized protocols and data templates are proposed, ensuring data quality and interoperability. Furthermore, the initiative intends to make use of citizen science in expanding observations and improving taxonomic coverage, highlighting platforms like iNaturalist for community engagement. Soil BON Earthworm seeks to unite global expertise and foster collaborative research to address critical gaps in understanding earthworm ecology and its implications for ecosystems at a global scale.

Endogean beetles (Coleoptera) of Guatemala: deep soil sampling and illustrated DNA barcode library

Manuel Barrios-Izás, Carmelo Andújar, Vasily V. Grebennikov — Mon, 01 Apr 2024 00:00:00 +0200

We document the diversity of endogean beetles discovered by us in the deep soil in Guatemala. They belong to eight families: Carabidae, Histeridae, Jacobsoniidae (first record for the country), Ptiliidae, Staphylinidae (subfamilies Aleocharinae, Leptotyphlinae, Osoriinae, Paederinae, Pselaphinae, Scydmaeninae, Staphylinidae), Scarabaeidae, Tenebrionidae, and Curculionidae. In total, we took 26 soil samples, each 20–40 litres in volume, and extracted from them 444 endogean adult beetles. To facilitate further studies of these poorly known organisms, often belonging to unnamed species and/or genera, we provide an open access online DNA barcode library containing 78 representative specimens (dx.doi.org/10.5883/DS-VGDS26). This is the first dedicated study highlighting the diversity of wingless and often eyeless beetles inhabiting the deep soil in Central America.

Pleistocene population differentiation in the ant Myrmica scabrinodis (Hymenoptera: Formicidae) – a taxonomic borderline case

Bernhard Seifert — Mon, 01 Apr 2024 00:00:00 +0200

Three taxa have been supposed in the past to be conspecific with or heterospecific from Myrmica scabrinodis Nylander 1846:
M. rugulosoides Forel 1915, M. pilosiscapus Bondroit 1920 and M. martini Seifert et al. 2014. The taxonomic relations of these taxa are investigated here based on 146 nest samples with 479 worker individuals collected in the whole Palaearctic range extending from the Pyrenees and England to South Central Siberia (Baikal region). Exploratory and hypothesis-driven data analyses considering 17 morphometric characters confirmed two main clusters: a western cluster distributed from 5°W to about 22°E and an eastern cluster occurring from 6°E to 104°E. The classification error of the exploratory data analyses NC-NMDS.kmeans and PCA relative to the controlling linear discriminant function (LDA) were 1.4 % and 0.7 % respectively. At the first hand, this seemed to justify considering the two clusters as separate species. The posterior probabilities of the type series when run as wild-card runs in a LDA were 0.9366 in M. rugulosoides, 0.9999 in M. martini, 0.0284 in M. scabrinodis and 0.0081 in M. pilosiscapus – allocating the former two to western cluster and the latter two to the eastern cluster. However, strong and highly significant reduction of morphological distance between the western and eastern cluster in the sympatric zone (ranging from 6°E to 22°E) compared to the situation in the allopatric ranges indicates frequent hybridization and introgression of genes. Due to this morphological convergence in sympatry, M. rugulosoides, M. pilosiscapus and M. martini are considered as junior synonyms of M. scabrinodis. The placement of the main Pleistocene refuge centers of M. scabrinodis concluded from data of this study is congruent to the picture derived from a mtDNA haplotype analysis of Leppänen et al. (2012) in Myrmica rubra (Linnaeus, 1758): South France and the Apennine Peninsula for the western group and the Balkans, Middle Asia and SW Siberia for the eastern group. Conclusions on nearly equal glacial retreat and postglacial expansion routes of M. scabrinodis and M. rubra are also supported by the high overlap of their realized niches found in the broad-based survey of Seifert (2017) and their almost congruent actual geographic ranges.

Genetic lineages of Parisotoma notabilis sensu lato (Collembola) in Eastern Europe and the Caucasus

Mon, 01 Apr 2024 00:00:00 +0200

Molecular genetic studies of springtails (Сollembola) reveal hidden diversity in many common species. Detailed studies of their distribution and ecology are necessary to clarify the taxonomic status of genetic lineages. This study contributes to the solution of these problems using the widespread polytypic species Parisotoma notabilis (Schäffer, 1896) sensu lato as a model object. The material was collected in 11 locations of Eastern Europe and 10 locations of the Caucasus. Genotyping was performed on a fragment of the CO1 marker gene and additionally on the D3-D5 region of the 28S gene. The phylogenetic tree and Automatic Barcode Gap Discovery (ABGD) and PTP analyses allowed to fine 10 lineages, of which 4 were new: L-Crimea, L-Cheget, L-Georgia, and L-Khosta. A lineage recently described from Iran has been found in Azerbaijan. Geographic distribution of lineages has been mapped. In Eastern Europe, the L1, L2, and L4-Hebert lineages are fairly evenly distributed. There are 10 lineages found in the Caucasus: L1 and L4-Hebert are the most common; various locally widespread lineages comprise some probably endemic to this region. In approximately half locations, 2—3 lineages are found together, but 4 lineages are the maximum co-inhabiting ones. Most lineages of P. notabilis s. l. are more or less confined to certain habitats, except the L4-Hebert lineage, which is recorded in most of the studied habitats. The other lineages of springtails living in the same area usually prefer different habitats. We suppose that genetic heterogeneity of P. notabilis s. l. combined with the ecological divergence of the most common lineages may partly explain the biological progress of this species in Eastern Europe.

On Oriental species of the genus Megalopinus Eichelbaum, 1915: one new species and taxonomical and biogeographical notes (Coleoptera, Staphylinidae, Megalopsidiinae)

Tobias Mainda — Mon, 01 Apr 2024 00:00:00 +0200

One new species, Megalopinus puthzianus spec. nov. from the Malacca Peninsula in Malaysia and Thailand, which was previously interpreted as Megalopinus hirashimai Naomi, 1986 is described. The species M. hirashimai is redescribed and its aedeagus is illustrated for the first time. The synonymy of Megalopinus tangi Puthz, 2012 and Megalopinus lapsus Mainda, 2022 syn. nov. (replacement name for M. modestus Puthz, 2021 nec (Sharp, 1886) is stated. The spelling of Megalopinus brancuccii Puthz, 2021 is established as the correct original spelling of this taxon and measurements and elytral punctuation numbers of additional specimens are added. A new record of Megalopinus creberrimus (L. Benick, 1941) with deviating coloration is reported from Mindanao (Philippines), and at the same time a new elytral puncture-row is designated: epipleural row - a row directly lateral to the sublateral row. Furthermore, the second male specimen of Megalopinus rolandmuelleri Mainda, 2022 is reported from Mindanao, Philippines, with additional measurements and elytral punctuation numbers. Finally, an updated checklist of all extant Megalopinus species of the Oriental and Australasian regions is presented.