Eur. J. Entomol. 123: 90-121, 2026 | DOI: 10.14411/eje.2026.011

Integrative taxonomy reveals a hidden diversity: Redescriptions and new records of Rhizoecidae (Sternorrhyncha: Coccomorpha) in GermanyOriginal article

Alejandro CABALLERO ORCID...1, Mehmet Bora KAYDAN ORCID...2, Andrea RAMOS-PORTILLA ORCID...3, Michael J. RAUPACH ORCID...4
1 Faculty of Biology, Ludwig Maximilian Universität, München, Germany and Section Hemiptera, Bavarian State Collection of Zoology (SNSB-ZSM), München, Germany; e-mail: alejandrocab66@gmail.com
2 Biotechnology Development and Research Centre, Çukurova University, Adana, Turkey; e-mail: bkaydan@gmail.com
3 Instituto Colombiano Agropecuario, Bogotá, Colombia; e-mail: andrea.ramos@ica.gov.co
4 Section Hemiptera, Bavarian State Collection of Zoology (SNSB-ZSM), München, Germany; e-mail: raupach@snsb.de

The scale insect family Rhizoecidae in Germany has historically been documented as comprising six species from two genera: Rhizoecus albidus Goux, 1942, Rhizoecus cacticans (Hambleton, 1946), Rhizoecus franconiae Schmutterer, 1956, Ripersiella caesii (Schmutterer, 1956), Ripersiella halophila (Hardy, 1868), and Ripersiella hibisci (Kawai & Takagi, 1971). To assess changes in this biodiversity, we collected 37 samples from potted plants across the botanical gardens of Berlin, Bonn, Frankfurt, Hamburg, and Munich. Species identifications were conducted using integrative taxonomy, combining morphological analysis of slide-mounted specimens, molecular data from the COI region, and ecological information. Our study identified eight species: Geococcus coffeae Green, 1933, Rhizoecus arabicus Hambleton, 1976, Rh. cacticans, Rhizoecus dianthi Green, 1926, Rhizoecus nemoralis (Hambleton, 1946), Rhizoecus falcifer Kunckel d'Herculais, 1878, Rhizoecus simplex (Hambleton, 1946) and Ripersiella aloes (Williams & Pellizzari, 1997). Except for Rh. cacticans, all are newly recorded for Germany, increasing the total German Rhizoecidae fauna to 13 species across three genera. We provide detailed morphometric redescriptions for Rh. arabicus, Rh. franconiae, Rh. simplex, and Ri. caesii based on type material, along with morphological notes for the other species. The study also resolves nomenclatural issues for Rh. franconiae and Ri. hibisci designating Lectotypes and reports 61 new host records for eight species. We present a taxonomic key for the updated list of Rhizoecidae species recorded in Germany. This research significantly revises the understanding of rhizoecid diversity in the country, revealing that the fauna is more than twice as rich as previously known.

Keywords: Root mealybugs, invasive species, barcoding

Received: November 28, 2025; Revised: March 9, 2026; Accepted: March 9, 2026; Published online: March 25, 2026  Show citation

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CABALLERO, A., KAYDAN, M.B., RAMOS-PORTILLA, A., & RAUPACH, M.J. (2026). Integrative taxonomy reveals a hidden diversity: Redescriptions and new records of Rhizoecidae (Sternorrhyncha: Coccomorpha) in Germany. EJE, 123, Article 90-121. https://doi.org/10.14411/eje.2026.011
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