Inclusion of juvenile stages improves diversity assessment and adds to our understanding of mite ecology – A case study from mires in Norway

Arachnid orders, Mesostigmata, Trombidiformes, and Sarcoptiformes, commonly known as ‘mites’, are abundant in mires, both as adults and as juveniles. However, due to the challenges of identification, the juvenile forms are often excluded from analyses. This is the first study in mires that included all three mite orders identified to the species level, including juvenile instars. We aimed to compare how diversity and the response to ecological variables differed if only the adults (ad) vs. the total number of specimens (ad+juv) are considered. Samples of 20 Sphagnum species (five subgenera) were collected and mites were extracted using Berlese funnels. Overall, nearly 60,000 mites were analyzed; of these Mesostigmata made up 1.87% of the total, Trombidiformes −0.27%, and Sarcoptiformes −97.86%. The study revealed 154 species (33 Mesostigmata, 24 Trombidiformes, and 97 Sarcoptiformes), the highest diversity of mites ever reported from mires. The inclusion of juveniles increased observed species richness by 6%, with 10 species (one Mesostigmata, six Trombidiformes, and three Sarcoptiformes) represented only by juvenile forms. Seventeen species are new to Norway (four Mesostigmata, one Sarcoptiformes, and 12 Trombidiformes, including five undescribed species of Stigmaeidae and Cunaxidae). Four of these were represented in the samples only by juveniles. Including the juveniles explained a greater amount of the variability of Trombidiformes (explanatory variables account for 23.60% for ad, and 73.74% for ad+juv) and Mesostigmata (29.23% − ad, 52.91% − ad+juv), but had less of an impact for Sarcoptiformes (38.48% − ad, 39.26% − ad+juv). Locality, Sphagnum subgenus and species, wetness, and trophic state significantly affected the mite communities and should be taken into consideration when studying mires. Since juvenile stages contribute significantly to mite diversity in mires, they should also be included in mite studies in other habitats.publishedVersio

Valgothrombium alpinum Willmann 1940

alpinum Willmann, 1940 [POSTLV] Valgothrombium alpinum Willmann, 1940: 253, Gabryś 1996: 218. Distribution. Austria, Poland.Published as part of Mąkol, Joanna & Łaydanowicz, Joanna, 2010, A new species of Valgothrombium Willmann, 1940, with additional taxonomic data for Valgothrombiinae genera known as larvae (Acari: Prostigmata: Microtrombidiidae), pp. 16-34 in Zootaxa 2647 on page 27, DOI: 10.5281/zenodo.19871

Valgothrombium africanum Andre 1958

africanum André, 1958 [POSTLV] Valgothrombium africanum André, 1958: 104. Distribution. Angola.Published as part of Mąkol, Joanna & Łaydanowicz, Joanna, 2010, A new species of Valgothrombium Willmann, 1940, with additional taxonomic data for Valgothrombiinae genera known as larvae (Acari: Prostigmata: Microtrombidiidae), pp. 16-34 in Zootaxa 2647 on page 27, DOI: 10.5281/zenodo.19871

Valgothrombium dubiosum Schweizer 1951

dubiosum Schweizer, 1951 [POSTLV] Valgothrombium alpinum var. dubiosum Schweizer, 1951: 107. Valgothrombium alpinum dubiosum: Schweizer & Bader 1963: 360. Valgothrombium dubiosum: Gabryś 1999: 147. Distribution. Switzerland.Published as part of Mąkol, Joanna & Łaydanowicz, Joanna, 2010, A new species of Valgothrombium Willmann, 1940, with additional taxonomic data for Valgothrombiinae genera known as larvae (Acari: Prostigmata: Microtrombidiidae), pp. 16-34 in Zootaxa 2647 on page 28, DOI: 10.5281/zenodo.19871

Valgothrombium melindae Haitlinger 2008

melindae Haitlinger, 2008 [LV] Valgothrombium melindae Haitlinger, 2008: 391. Distribution. Moldova, Ukraine. Remarks. Scutum and scutellum of V. melindae are shown in Figure 11. In the original description Haitlinger (2008) provided the following characteristics of leg chaetotaxy (trochanter - tarsus): leg I − Tr (1 n) - Fe (5 n, 1 θ) - Ge (4 n, 1 σ) - Ti (6 n, 2 φ) - Ta (14 n, 2 ζ, 1 ω); leg II − Tr (1 n) - Fe (4 n, 1 θ) - Ge (2 n, 1 σ) - Ti (4 n, 2 φ) - Ta (10 n, 1 ω); leg III − Tr (1 n) - Fe (3 n) - Ge (2 n, 1 σ) - Ti (5 n) - Ta (10 n). Our examination of the holotype allowed us to verify some data concerning the chaetotaxy, which should be interpreted as follows (data which could not be confirmed due to the condition of the specimen, are queried): leg I − Tr (1 n) - Fe ([?] 5 n) - Ge (4 n, 2 σ, [?] 1 κ) - Ti (6 n, 2 φ) - Ta ([?] 14 n, 2 ζ, 1 ω, 1 ε); leg II − Tr (1 n) - Fe ([?] 5 n) - Ge (2 n, 1 σ) - Ti (5 n, 2 φ) - Ta ([?] 10 n, 1 ζ, 1 ω, 1 ε); leg III − Tr (1 n) - Fe (4 n) - Ge (2 n, 1 σ) - Ti (5 n) - Ta ([?] 10 n). Coxa I bears two bifurcate setae. Two setae placed in most proximal position on femur III are smooth. Famulus (ε) on tarsus I is located in more distal position in relation to solenidion (ω).Published as part of Mąkol, Joanna & Łaydanowicz, Joanna, 2010, A new species of Valgothrombium Willmann, 1940, with additional taxonomic data for Valgothrombiinae genera known as larvae (Acari: Prostigmata: Microtrombidiidae), pp. 16-34 in Zootaxa 2647 on page 29, DOI: 10.5281/zenodo.19871

Enemothrombium bifoliosum Canestrini 1884

bifoliosum (Canestrini, 1884) [POSTLV, LV] Trombidium bifoliosum Canestrini, 1884: 693. Enemothrombium bifoliosum: Hull 1918: 16; Wohltmann & Gabryś 2006: 814 (description of larva). For detailed synonymy see Gabryś (1999). Distribution. Czech Republic, Germany, Hungary, Italy, Norway, Poland, Romania, Spain. Remarks. Description of two solenidia on genu II for Enemothrombium bifoliosum and Valgothrombium valgum larvae, as listed in table 2 of Wohltmann and Gabryś (2006), is wrong and should be replaced with one solenidion, as shown in the figures (Wohltmann & Gabryś 2006; Wohltmann & Wendt 1996).Published as part of Mąkol, Joanna & Łaydanowicz, Joanna, 2010, A new species of Valgothrombium Willmann, 1940, with additional taxonomic data for Valgothrombiinae genera known as larvae (Acari: Prostigmata: Microtrombidiidae), pp. 16-34 in Zootaxa 2647 on pages 26-27, DOI: 10.5281/zenodo.19871

Ctenerythraeus queenslandiae Womersley 1942

queenslandiae (Womersley, 1942) [POSTLV] Echinothrombium queenslandiae Womersley, 1942: 176. Spathulathrombium queenslandiae: Womersley 1945: 305 [as " Spathulathrombium queenslandiae sp. nov. "]. Ctenerythraeus queenslandiae: Southcott 1957: 135. Distribution. Australia.Published as part of Mąkol, Joanna & Łaydanowicz, Joanna, 2010, A new species of Valgothrombium Willmann, 1940, with additional taxonomic data for Valgothrombiinae genera known as larvae (Acari: Prostigmata: Microtrombidiidae), pp. 16-34 in Zootaxa 2647 on page 26, DOI: 10.5281/zenodo.19871

Valgothrombium copiosum Shiba 1976

copiosum (Shiba, 1976) [POSTLV] Dromeothrombium copiosum Shiba, 1976: 200. Valgothrombium copiosum: Gabryś 1999: 147. Distribution. Malaysia.Published as part of Mąkol, Joanna & Łaydanowicz, Joanna, 2010, A new species of Valgothrombium Willmann, 1940, with additional taxonomic data for Valgothrombiinae genera known as larvae (Acari: Prostigmata: Microtrombidiidae), pp. 16-34 in Zootaxa 2647 on page 28, DOI: 10.5281/zenodo.19871

Ctenerythraeus maximus Womersley 1945

maximus (Womersley, 1945) [POSTLV, LV] Spathulathrombium maximum Womersley, 1945: 305. Ctenerythraeus maximus: Southcott 1957: 135, Southcott 1994: 67 (description of larva). Distribution. Australia, Tasmania.Published as part of Mąkol, Joanna & Łaydanowicz, Joanna, 2010, A new species of Valgothrombium Willmann, 1940, with additional taxonomic data for Valgothrombiinae genera known as larvae (Acari: Prostigmata: Microtrombidiidae), pp. 16-34 in Zootaxa 2647 on page 26, DOI: 10.5281/zenodo.19871