Host plant richness and abundance drive populations of a super-generalist xylem-feeding insect - Raw data
Data files
Feb 05, 2026 version files 66.70 KB
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Juveniles_and_adults.csv
38.32 KB
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Juveniles_merged.csv
4.22 KB
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Juveniles.csv
20.44 KB
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README.md
3.72 KB
Abstract
Due to their wide diet breadth, generalist herbivores are often less sensitive to bottom-up forces compared to specialists. Despite this, some generalist insects can be significantly affected by the diversity and structure of the plant communities. Here, we investigated the effect of habitat and plant richness on the abundance of the super-generalist meadow spittlebug, Philaenus spumarius (Hemiptera: Aphrophoridae). We sampled 93 sites representing four habitat types (olive groves, vineyards, meadows, and field margins) across eight heterogeneous agricultural landscapes in central Italy. Nymphs were sampled by quadrat sampling in April along with the herbaceous vegetation community, while adults were sampled using a sweep net in June, August, and October. Nymph abundance was positively associated with plant richness and vegetation cover at a small scale (2 m2), a scale consistent with the limited movement capability of nymphs, while it did not differ between habitat types. A positive correlation between adult and juvenile densities was also observed. However, this effect weakened towards the end of the growing season. The findings indicate that bottom-up effects associated with plant community composition can significantly influence the local abundance of a super-generalist xylem-feeding insect. The positive relationship between plant species richness and nymph abundance suggests that broad host use does not necessarily buffer P. spumarius from local vegetation effects. Furthermore, the marked weakening of the juvenile–adult abundance relationship is consistent with increased dispersal activity happening in the fall in our study area. Given that P. spumarius exhibits variation in host use and population dynamics across its geographic range, the strength of bottom-up effects in this species, as well as its dispersal patterns, are likely context-dependent and may vary across environmental and geographical settings.
Dataset DOI: 10.5061/dryad.9p8cz8ww2
Description of the data and file structure
This dataset contains field sampling data on the meadow spittlebug, Philaenus spumarius, collected in eight agricultural landscapes in the Abruzzo region (central Italy). The data include counts of juveniles and adults, together with information on vegetation structure and plant richness. The dataset is intended to support ecological and agroecological analyses of P. spumarius population dynamics and habitat associations, with relevance for pest and vector management.
Time period and location
Temporal coverage: April, June, August, and October 2022
Geographic coverage: Abruzzo region, Italy
Habitat types: olive groves, meadows, vineyards, cultivated field margins
Files and variables
Data Files
All files are provided in comma-separated values (.csv) format without formatting, merged cells, formulas, or filters.
1. Juveniles.csv
Replicate-level quadrat observations (2 m²).
Each row represents one quadrat.
Key variables:
- Landscape_id: landscape identifier
- Site_id: sampling site identifier among each landscape
- Replicate_id: 2 m² quadrat replicate identifier (1–5) among each site
- Habitat_type: habitat category
- Philaenus_spumarius_count: number of nymphs (count) recorded within the quadrat
- Vegetation_cover_percentage: herbaceous vegetation cover (%) recorded within the quadrat
- Vegetation_height_cm: herbaceous vegetation height (cm) recorded within the quadrat
- Plant_species_count: number of herbaceous plant species (count) recorded within the quadrat
- Plant_genera_count: number of herbaceous plant genera (count) recorded within the quadrat
- Plant_families_count: number of herbaceous plant families (count) recorded within the quadrat
2. Juveniles_merged.csv
Plot-level aggregated data derived from juveniles.csv.
Each row represents one sampling site.
Key variables:
- Landscape_id: landscape identifier
- Site_id: sampling site identifier among each landscape
- Habitat_type: habitat category
- Philaenus_spumarius_count: number of nymphs (count) recorded within the site
- Vegetation_cover_percentage: mean herbaceous vegetation cover (%) recorded within the site
- Vegetation_height_cm: mean herbaceous vegetation height (cm) recorded within the site
- Plant_species_count: total number of herbaceous plant species (count) recorded within the site
- Plant_genera_count: total number of herbaceous plant genera (count) recorded within the site
- Plant_families_count: total number of herbaceous plant families (count) recorded within the site
3. Juveniles_and_adults.csv
Plot-level seasonal sampling including juveniles and adults.
Each row represents one site × sampling month × life stage × position.
Key variables:
- Landscape_id: landscape identifier
- Site_id: sampling site identifier among each landscape
- Habitat_type: habitat category
- Sampling_round: sampling rounds in chronological order (A-D)
- Sampling_month: sampling round months (April, June, August, October)
- Life_stage: sampled life stage (juvenile, adult)
- Position: sampling position (ground, canopy)
- Philaenus_spumarius_count: number of P. spumarius (count) recorded
Missing Values
In 3. Juveniles_and_adults.csv, NA occurs in rows corresponding to juveniles on canopy vegetation. These NA values can be interpreted as 0 for analysis, because Philaenus spumarius only develop on ground vegetation.
Legal and Ethical Statement
The dataset does not contain information on human subjects.
Sampling period: late April 2022.
Method: quadrat sampling along 20 m transects positioned diagonally across each site.
Replicates: five quadrats (2 m² each) per site.
All nymphs within each quadrat were counted.
Vegetation variables recorded per quadrat:
- vegetation cover (%)
- vegetation height (cm)
- plant richness (counts of species, genera and families)
Sampling periods: late June, mid-August, mid-October 2022.
Method: sweep net sampling.
Sampling effort: 80 sweeps on ground vegetation + 180 sweeps on woody canopy vegetation of each plot.
Counts are provided separately by sampling position (ground vs canopy).
No pest control or vegetation management targeting P. spumarius was applied in sampled habitats.
