Reh-Back in Europe : Quamtana spiders ( Araneae : Pholcidae ) in Germany

Two undescribed species of the African pholcid spider genus Quamtana have been found in German greenhouses and plant markets since 2012. Both species seem to have established stable populations. This genus has not been previously recorded from Europe, except for a fossil specimen in Eocene amber from the Paris Basin that was tentatively assigned to Quamtana and that is estimated to date from 53 million years ago. Since the actual geographic origins of the two species (probably South and/or tropical Africa) are unknown, we do not formally

Spiders can reach new regions, countries, and continents in many ways.While some species expand their areas of distribution naturally, most alien species seem to have been introduced by human activities (Kobelt & Nentwig 2008).In recent years, several findings of non-native spiders were reported in Germany (e.g., Kielhorn & Rödel 2011, Schäfer & Deepen-Wieczorek 2014, Šestáková et al. 2014, Sührig 2010).Potted plants may be among the most important vectors.As a result, many new species can be found in facilities displaying or selling exotic plants (Reiser 2013).
The pholcid spider genus Quamtana Huber, 2003 currently includes 26 described extant species (World Spider Catalog 2015).Most of these small to tiny shrub and litter-dwelling species are found in South Africa, but a few species occur further north in tropical Africa (Guinea, Cameroon, Congo DR, Uganda, Rwanda, Kenya, Tanzania, Angola; Huber 2003, Huber & Warui 2012, Huber & Kwapong 2013, Huber et al. 2014).Recently, Penney (2007) described a fossil specimen from Eocene amber from the Paris Basin in France and tentatively assigned the species to the genus Quamtana.This amber is estimated to date from 53 million years ago, when the region may have had a climate similar to that in southern Africa today (Nel et al. 2004).
In this short note we report on findings of two different species of Quamtana in German plant markets and greenhouses where they seem to have established viable populations.Both species are undescribed and will not be formally described here because their actual geographic origins are unknown.Many undescribed species of African Quamtana exist in collections (B.A. Huber unpubl.data) and the two German species reported below may well be among them.feldt), 2) 3( in ZFMK (Ar 12708).Thüringen, Jena, Botanical Garden (50°55.9'N,11°35.1'E;~170 m a.s.l.), 06.02.2012 (A.Grabolle), 1) in ZFMK (Ar 12709).
Natural history.The Witzenhausen specimens were collected in the humid leaf litter and under stones of a greenhouse.The first specimens were collected in 2013, and a further visit in 2015 (by SR) revealed numerous specimens (in addition to those collected), including females with egg-sacs and juveniles.This suggests that this is an established population rather than continuous introductions.The Jena specimen was collected in the succulent house of the botanical garden, under stones of a lining wall along the path.Preliminary diagnosis.This species is very similar to Q. mabusai Huber, 2003, but differs in shapes of procursus (compare Figs 17 and 19) and bulbal apophysis (compare Figs 18 and 20).Females may be indistinguishable.
Preliminary description.Body length ~1.5 mm; tibia 1 length in 5 males: 2.3-3.2(mean 2.7), in 7 females: 1.8-2.1 (mean 1.9).Coloration mostly pale ochre to light brown, with distinct dark median band on carapace (Figs 3-5).Male chelicerae with pair of frontal apophyses as in Q. mabusai (cf.fig.140 in Hu- Natural history.The specimens were found in the edges of u-shaped iron-pillars and under the lips of big flower pots.These pots are apparently rarely moved so that there is a low frequency of disturbance.In March 2015 we observed many more specimens (> 20) than collected.However, only two males were found during that search.In January as well as in March, several females with egg sacs and juveniles were found.This suggests that the species reproduces in the locality.From the high number of specimens seen and from the wide distribution over a large area of the market we conclude that the species has been at the locality for several generations.The temperature of the air and of the iron pillars was about 16 °C, measured with an electric thermometer.
Temperature in the greenhouse is permanently above 22 °C and can reach up to 38 °C in summer.Plants are watered weekly and only biological pest control is applied.Other than Quamtana sp.A, specimens of Stenochrus portoricensis Chamberlin, 1922 (Schizo mida: Hubbardiidae) (cf.Armas & Rehfeldt 2015) and Triaeris stenaspis Simon, 1891 (Araneae: Oonopidae) (cf.Korenko et al. 2014) were found in the same microhabitat.