Arachnologische Mitteilungen 56

52 N. Milasowszky & M. Hepner average niche positions in open habitats (Entling et al. 2007, Appendix S2), while within the moisture gradient their niche positions slightly differed; T. scabriculus could thus be consi- dered as an inhabitant of mesic moist habitats, while T. cirri- frons as one of mesic dry habitats. However, niche width va- lues indicate a wide niche range in both species/forms, i.e. a great niche overlap within the moisture gradient. In the distribution maps of the “Nord” and “Pas-de- Calais” departments of northern France, six records exist of T. cirrifrons that overlap with the records of T. scabriculus to 100 % (Lecigne 2016). Of interest here is that fact that 26 of the overall 33 records of T. scabriculus were located on the coast (Lecigne 2016: 212). Furthermore, in Bulgaria, where T. scabriculus also occur, the first record of T. cirrifrons was made by Deltshev (2004) in a pine forest near Sandansky, where he uncovered three cirrifrons and no scabriculus males. Perhaps this exclusive occurrence of the form cirrifrons is the reason for its entry in the spider checklist of Bulgaria. Delts- hev (2004) commented that the locality in Bulgaria is at the southeastern border of its range. However, Mikhailov (1996, 1997) previously documented T. cirrifrons [as a junior syno- nym of T. scabriculus ] from Russia (e.g. Russian Plains, Urals, and Middle Siberia) and the Ukraine. Mikhailov & Trishina (2013) noticed one T. cirrifrons male form co-occurring with one male and two females of T. scabriculus in a birch and lime tree plantation in the vicinity of Pushta (Mordovian Repub- lic, Russia) on 19 August 2011. According to Roberts (1987), T. scabriculus and T. scabriculus f. cirrifrons have a similar dis- tribution throughout the British Isles. However, both forms do not always occur together, rather they are locally common in dry habitats.Thus, T. scabriculus and its form cirrifrons have a widespread but patchy distribution in much of Britain. In summary, both forms are extensive in western and central Eu- rope, and their distribution range extends east to Russia and the Far East. Phenology Simon (1884) stated that the form cirrifrons is “commun au premier printemps dans les détritus humides” [common in early spring in moist litter].Wiehle (1960) reported one male of the form cirrifrons from Germany, 4 October 1958, and another male, 12 June 1958. Larsen & Bøggild (1970) regis- tered T. scabriculus males in June, July, August and October, and T. cirrifrons in June and August. Females were present in April, May, June, July, August and October. Thaler (1986) recorded one cirrifrons male in the period from 24 April to 5 May, and one cirrifrons male in the period from 5 to 19 May. Von Broen (1977) reported T. scabriculus / cirrifrons from ur- ban ruderal areas in Berlin, Germany, and presented the phe- nology data of both forms over one calendar year. According to this data, T. scabriculus males occurred from the beginning of March until the end of November. Nine specimens of T. cirrifrons were collected in April, May and June. According to von Broen (1977), the activity peak of adult males was in April. Since the species could be found nearly all year round, von Broen characterized it as eurychronus. Adult females may be present throughout the year but there is a peak in recorded number of adults of both sexes in late spring and early sum- mer, and again in the autumn (Harvey et al. 2002). Mikhailov & Trishina (2013) discovered one T. cirrifrons male form co- occurring with one male and two females of T. scabriculus on 19 August 2011. In our study, we noted that the highest peak of activity of T. scabriculus was in the months February and March (Fig. 3), which is about a month earlier than in the study from Berlin where the maximum lies between March and April (von Broen 1977). According to the phenology fi- gure in Harvey et al. (2002), the activity peak in the United Kingdom seems to be in May. Male morph ratio within populations Simon (1884: 645) stated: “La forme cirrifrons se trouve tou- jours mêlée au type, mais elle est partout plus rare” [the form cirrifrons is always mixed with the type, but it is everywhere rarer]. Based on their findings, von Broen & Moritz (1965) arrived at the same conclusion that the variety T. scabriculus cirrifrons occurs in all populations of T. scabriculus . In general, this is true, although there are many exceptions (e.g. see the T. scabriculus / cirrifrons maps of Lecigne 2016). Roberts (1987) summarized the up-to-date data and concluded that T. sca­ briculus f. cirrifrons was rather less common than the typical form T. scabriculus . In general, this is true, but there are excep- tions or even populations of T. scabriculus that consist purely of cirrifrons males. To give an example, Deltshev (2004) do- cumented three cirrifrons males in a pine forest in Bulgaria without any scabriculus morphs. Pickard-Cambridge (1860, 1871) was the first to quantify the ratio between the male form of T. scabriculus and cirrifrons as “abundant” to “one”. In our data set we obtained a ratio of 95:5 = 19:1.Thaler (1986) documented 69 males of the form scabriculus and two males of the form cirrifrons in a floodplain area near Vienna, Austria; hence, the ratio between the typical form and “ cirrifrons ” was about 35:1. Interestingly, in two re- lictual floodplain forests along the Inn River in Tyrol, Austria, Steinberger & Thaler (1990) counted about 45 T. scabriculus males in the study site “Kufstein” (large floodplain forest on the right river bank) and one “ cirrifrons ” male in the study site “Langkampfen” (small floodplain forest strip on the left river bank), i.e. both forms seemed co-occur in the same study area, but not in the same study sites. In Aldenhoven, Ger- many, Esser (1997) identified two cirrifrons males together with 64 T. scabriculus specimens (probably mostly males) in a small ryegrass-plantain field margin strip (300 m length, 3 m width) situated between an arable field and an asphalt road; hence the ratio of scabriculus and cirrifrons was at a maxi- mum of 32:1, but probably a little lower due to the unknown number of females. Von Broen (1977) accounted for both T. scabriculus and cirrifrons from three urban ruderal areas in Berlin, Germany, (i) a “Ligusterhecke” [privet hedge], (ii) an “Erdbeerbeet” [strawberry patch] and (iii) a “Holzmehlflä- che zwischen Ziegelbau und Holzschuppen” [an area covered with saw dust between a brick building and a woodshed]. In the privet hedge, the ratio between T. scabriculus and T. cirri­ frons males was about 14:1 (164 T. scabriculus , 12 T. cirrifrons ), while in the strawberry patch and the sawdust site only T. scabriculus specimens were captured. Von Broen (1977) also provided unpublished data on the ratio of the two forms from Greifswald, where he captured 10 T . scabriculus males and two T. cirrifrons males; hence, there the ratio was 5:1. Dekkers- Scheutjens (2010) collected 31 T . scabriculus males in a study site within a nature reserve southwest of Tilburg (Nether- lands) together with three cirrifrons forms, i.e. the ratio was about 10:1.