DOI: 10.5061/dryad.dv41ns2bw
title: Where water meets rock: Ecological niches and diversity hotspots of hygropetric beetles in the Neotropics

description: Freshwater biodiversity is structured by climate and topography controls
 on moisture at fine scales. Hygropetric habitats (thin water films over
 rock) remain underrepresented in macroecology. We tested whether major
 Neotropical areas occupy distinct environmental space, whether hygropetric
 beetle genera show low niche overlap, and quantified richness in
 mountainous and topographically steep regions. We assembled 144 species in
 15 genera across seven families from taxonomic literature, GBIF, and
 targeted field sampling at 97 waterfalls and streams in the Brazilian
 Shield, including 66 new occurrences. Species distribution models, using
 five algorithms and predictors that included bioclimatic variables,
 elevation, compound topographic index, and profile curvature, were
 cross-validated. Multivariate analyses compared environmental space among
 provinces, and niche overlap metrics assessed intergeneric segregation.
 Major Neotropical areas occupied significantly different environmental
 space, and genera formed ecologically distinct groups with low niche
 overlap, indicating environmental partitioning and some convergence onto
 similar moisture and energy regimes across disjunct regions. Mountainous
 areas were richness hotspots, with the Brazilian Shield representing 40%
 of species richness, the Guiana Shield 33%, the Andes 19%, and the
 Northern Neotropics 8%. Integrating macroecology, niche modelling, and new
 field data yields a scalable approach to forecasting hygropetric
 biodiversity. It closes key knowledge gaps for Neotropical beetles and
 improves planning for freshwater biodiversity conservation.
description: # Where water meets rock: Ecological niches and diversity hotspots of
 hygropetric beetles in the Neotropics Dataset DOI:
 [10.5061/dryad.dv41ns2bw](https://doi.org/10.5061/dryad.dv41ns2bw) ##
 Description of the data and file structure This dataset accompanies the
 study *Where water meets rock: Ecological niches and diversity hotspots of
 hygropetric beetles in the Neotropics* and documents the environmental
 predictors used, model evaluation thresholds, and compiled occurrence
 records for hygropetric beetle taxa across the Neotropics. Data were
 assembled from public environmental layers and curated species‑occurrence
 records (GBIF and taxonomic literature) to support species distribution
 modelling (SDM) and downstream diversity analyses. The occurrence table
 includes vetted geographic coordinates and a per‑record “Filter” flag
 indicating whether each record was retained ("Used") or excluded
 after quality control. Environmental variables include bioclimatic,
 elevation, and terrain‑derived layers. ### Files and variables #### File:
 Supplementary_material_S1.pdf **Description:** master document listing
 environmental variables and their sources; model threshold metrics and
 values by taxon; and the compiled occurrence records table with provenance
 and curation flags. * **Table S2** – Sources and coordinates for raw
 occurrence records (post‑vetting status indicated in *Filter* column):
 raw_records_compiled.xls.x **Note on derived occurrence files:**\ All
 tab-delimited `.txt` files containing occurrence records used in the
 analyses are exports derived from the master spreadsheet
 `raw_records_compiled.xlsx` (Table S2 in *Supplementary_material_S1.pdf*).
 In particular, the following files are filtered or restructured versions
 of this main table: * `dados_full2.1.txt` – occurrence table used for
 calculating species richness by genus and region (Section 2 of the
 analysis script); * `hygropetric_occurrences_genus.txt` – occurrence table
 aggregated by genus, used for macro-area richness analyses (Section 3 of
 the analysis script); * `dados_full2.txt` – occurrence table combined with
 PCA scores for niche overlap and environmental differentiation analyses
 (Sections 4–7 of the analysis script). ## Occurrence records (Table S2)
 Columns and meanings: * `Genus` – Genus name * `species` – Species epithet
 * `family` – Family assignment (e.g., Hydrophilidae, Dytiscidae,
 Hydraenidae, Torridincolidae) * `source1` – High‑level source (e.g.,
 `Gbif`) * `source` – Specific provenance (e.g., “article taxonomy”, “New
 record”, author/year) * `Filter` – Curation status after vetting (`Used` =
 retained; `Exclued` = excluded as listed in S1) * `longitude`, `latitude`
 – Geographic coordinates (decimal degrees) * `localization` – Broad region
 tag (e.g., Andes, Guiana Shield, Brazilian Shield, North Neotropic)
 **Coordinate system:** Datum WGS84. ## Environmental predictors (rasters)
 **Climate variables (WorldClim v2.1):** * `BIO1` – Annual Mean
 Temperature (0.1 °C) * `BIO2` – Mean Diurnal Range (mean of monthly (max
 temp − min temp)) (0.1 °C) * `BIO3` – Isothermality (BIO2/BIO7 ×
 100) (unitless; % scale) * `BIO4` – Temperature Seasonality (standard
 deviation × 100) (unitless; % scale) * `BIO5` – Max Temperature of Warmest
 Month (0.1 °C) * `BIO6` – Min Temperature of Coldest Month (0.1 °C) *
 `BIO7` – Temperature Annual Range (BIO5 − BIO6) (0.1 °C) * `BIO8` – Mean
 Temperature of Wettest Quarter (0.1 °C) * `BIO9` – Mean Temperature of
 Driest Quarter (0.1 °C) * `BIO10` – Mean Temperature of Warmest
 Quarter (0.1 °C) * `BIO11` – Mean Temperature of Coldest Quarter (0.1 °C)
 * `BIO12` – Annual Precipitation (mm) * `BIO13` – Precipitation of Wettest
 Month (mm) * `BIO14` – Precipitation of Driest Month (mm) * `BIO15` –
 Precipitation Seasonality (coefficient of variation) (%) * `BIO16` –
 Precipitation of Wettest Quarter (mm) * `BIO17` – Precipitation of Driest
 Quarter (mm) * `BIO18` – Precipitation of Warmest Quarter (mm) * `BIO19` –
 Precipitation of Coldest Quarter (mm) **Physiographic variables:** *
 `Elevation` – digital elevation model (WorldClim v2.1) (m a.s.l.) * `CTI`
 – Compound Topographic Index (terrain wetness index) (radians per metre;
 rad/m) * `Pcurv` – Profile curvature (terrain curvature along
 slope) (radians per metre; rad/m) ## Access information We confirm that
 the dataset, in the form submitted to Dryad, is compatible with Dryad’s
 requirements. The package consists of (i) occurrence records generated by
 our team (new records) and (ii) harmonized occurrence metadata compiled
 from openly accessible sources. No copyrighted material or third-party
 content under restrictive licenses is redistributed in this submission.