This study reports the first records of two spider species for Hungary: Cyclosa sierrae Simon, 1870 (Araneidae) and Porrhomma oblitum (O. P.-Cambridge, 1871) (Linyphiidae). Cyclosa sierrae also represents the first record of this species from Central Europe. Furthermore, we provide evidence about the occurence of Dysdera lata Reuss, 1834 and Philodromus marmoratus Kulczyński, 1891 in Hungary and for six further species we report new data: Brigittea vicina (Simon, 1873) (Dictynidae), Iberina microphthalma (Snazell & Duffey, 1980) (Hahniidae), Mermessus trilobatus (Emerton, 1882) (Linyphiidae), Pulchellodromus ruficapillus (Simon, 1885) (Philodromidae), Lasaeola prona (Menge, 1868) (Theridiidae) and Diaea livens Simon, 1876 (Thomisidae). Comments on the distribution, biology and taxonomy of the ten mentioned spider species are provided.

First records of spiders and harvestmen (Arachnida: Araneae, Opiliones) for Schleswig-Holstein (Germany) since 2010 with remarks on endangerment status. In the years 2004 to 2017 the author has recorded 25 spider species and one harvestman newly for Schleswig-Holstein. The unpublished records since 2010 are presented for the first time: 2010: Araniella inconspicua (Simon, 1874); 2011: Hahnia ononidum Simon, 1875; 2012: Centromerus incilium (L. Koch, 1881); 2013: Mermessus trilobatus (Emerton, 1882); 2014: Anelasmocephalus cambridgei Westwood, 1874, Glyphesis servulus (Simon, 1881), Micrargus apertus (O. P.-Cambridge, 1871) and the lost harvestman Lacinius horridus (Panzer, 1794); 2015: Cheiracanthium campestre Lohmander, 1944, Improphantes decolor (Westring, 1861), Sibianor larae Logunov, 2001; 2017: Clubiona leucaspis (Simon, 1932). In addition, remarks on endangerment status with respect to earlier records since 2004 are provided.

Kryptonesticus georgescuae spec. nov., a blind troglobitic spider species from the mesothermal sulfidic Movile Cave (Romania), is described and illustrated based on two female specimens. The male is unknown. The relationship between this new species and other European species of Nesticidae is discussed.

Studies of subterranean habitats in Slovakia revealed two rare linyphiid spider species new to the country, Pseudomaro aenigmaticus Denis, 1966 and Pseudocarorita thaleri (Saaristo, 1971). Pseudomaro aenigmaticus was recorded in the Malé Karpaty Mountains in western Slovakia. A male was captured in the limestone Plavecká Cave and a female was found in a granitoid mesovoid shallow substratum (MSS) in the Jajcajov jarok Valley. One pair of Pseudocarorita thaleri was found in the MSS in the Belinské skaly Nature Monument in the Cerová vrchovina Highland in southern Slovakia. This study also presents the characteristic habitus and habitats of the recorded spiders.

The final instar larvae of the koinobiont ectoparasitoids in the Polysphincta group of genera induce their host spiders to construct webs that protect the wasp pupa during its development. It has been hypothesized that changes in structure and design in the cocoon web correlate with the duration and characteristics of the normal web. Kapogea cyrtophoroides (Araneidae) construct long-lived, strong normal webs; the cocoon web induced by Hymenoepimecis heidyae (Ichneumonidae) is nearly identical to the normal web, providing support for the hypothesis. The larva constructs its cocoon in the centre of the host's dense web, connecting it to the spider web and following the same behavioural pattern of construction described for other wasp species in the same group. The behaviour induced in the spider as well as the cocoon construction is very stereotypic, and consistent with other species, but modifications in the cocoon web seem to be strongly determined by the characteristics and design of the spiders' normal web.

Giovanni Canestrini (1835–1900) was the pioneer of arachnology in Italy, who published the first catalogue of Italian spiders and a total of 87 papers in the field. His interests covered almost all the Italian arachnid orders, although in the last part of his life he focused on acarology, in which he became a leading world expert. The remains of Canestrini's arachnological collection deposited in the Zoology Museum of Padova University are represented by spiders (about 850 tubes), mites (438 microscope slides, 115 tubes), harvestmen (120), pseudoscorpions (63), scorpions (19) and solifuges (1). The collection is now part of a large revision project aiming at better understanding and clarifying the scientific heritage of Canestrini, including an inventory of the type material from Canestrini and other European arachnologists who contributed to his collection (e.g., T. Thorell). The first results of the collection revision outlining different arachnid orders and highlighting the occurrence of type material are presented here. Brief historical information on Canestrini and his pupils is also provided.

Three different types of the names used in spider systematics are recognized and discussed: 1) typified taxonomic names, 2) non-typified taxonomic names, and 3) non-taxonomic names. Typified names are those from genus to superfamily group names; they are regulated by the ICZN. Non-typified names are used for taxonomic groups higher than superfamilies (e.g., Haplogynae, Mesothelae, etc.); they are not regulated by the ICZN but have an authorship, a fixed year of publication and are incorporated in a hierarchical classification. Non-taxonomic names are not regulated by any formal rules, unranked, have no authorship or description, and are non-typified. Some difficulties connected with the non-typified names in spider systematics are briefly discussed. Senior synonyms of some non-typified and non-taxonomic names are discussed, and suggestions are given on how to deal with the non-typified names lacking senior synonyms.

Zorocrates guerrerensis Gertsch & Davis, 1940 is a Mexican cribellate spider with almost no information about its biology. As the species could potentially be of medical interest, it was decided to study basic aspects of its life history under laboratory conditions. The life cycle lasts a year, with spiders undergoing up to 12 instars to reach maturity. The courtship behaviour includes tactile communication. Copulation consists of two palpal insertions, each with a single haematodochal expansion. Both males and females can mate more than once; components of the first and second copulation do not differ. On average, the total copulation duration lasts for more than five minutes. Some details of the copulation process are discussed and compared with those of other lycosoids.

Diplocephalus cristatus (Blackwall, 1833) is confirmed as a dimorphic species, having two morphs: cristatus and foraminifer. This view was first proposed by Georgescu (1969), but not supported in the literature. Diplocephalus foraminifer (O. Pickard-Cambridge, 1875), D. bicephalus (Simon, 1884), D. rectilobus (Simon, 1884), D. foraminifer thyrsiger (Simon, 1884) and D. arvernus (Denis, 1948) are here considered junior synonyms of D. cristatus (Blackwall, 1833). Diplocephalus bicephalus belongs to the morph cristatus, D. rectilobus, D. thyrsiger and D. arvernus to the morph foraminifer. A lectotype (♂) is designated for Diplocephalus bicephalus Simon, 1884; the paratype female of D. bicephalus was incorrectly identified and actually belongs to Dicymbium nigrum (Blackwall, 1834). Savignia harmsi Wunderlich, 1980 is another dimorphic species, with the two strongly differing male morphs: typica and cor.

A new gnaphosid spider species, Zelotes acarnanicus sp. n., is described from a male and female collected on the Perganti Mountain of the Acarnanian Mountains range in mainland Greece.

Leptodrassus albidus and Setaphis carmeli are reported for the first time for the Canary Islands, on the islands of Tenerife and Gran Canaria, respectively. Also, another 13 species representing first records for some of the individual Canarian major islands are reported. Habitats of collected specimens are described and global distribution of the species is provided.

Contribution to the jumping spider fauna (Araneae, Salticidae) of the Greek Dodecanese island of Rhodes, with a description of Pseudophrys rhodiensis and six new records. During a recent survey of jumping spiders on the Greek Dodecanese island of Rhodes, a total of 24 species from 21 genera were recorded. One species, Pseudeuophrys rhodiensis Schäfer sp. nov., is here described as new. Six further species of jumping spiders are newly recorded for the island; three of which (Aelurillus concolor, Evarcha insularis comb. nov. and Salticus noordami) are new for the entire Dodecanese. In addition, a number of taxonomic problems regarding the jumping spider fauna of Rhodes are briefly discussed.

The first record of the hygrophilous linyphiid spider Prinerigone vagans (Audouin, 1826) for Poland, collected on a bank of the River Olza near the Czech Border, is presented together with a discussion of known habitats of the species. A review of the taxonomic literature revealed that some characters of the male palp are highly variable within the distribution and even single populations of P. vagans. Future investigations should clarify the status of populations in Europe, the Near and Middle East as well as North Africa including Macaronesia.

Records of rare arachnids from forests in the Eastern Eifel (Rhineland-Palatinate, Germany) (Araneae: Agelenidae, Araneidae, Linyphiidae, Theridiidae; Opiliones: Ischyropsalididae). New species records for the Rhineland-Palatinate (Germany) from studies in forests from the Eastern Eifel region are reported. Ischyropsalis hellwigii hellwigii (Panzer, 1794) is recorded for the first time west of the river Rhine. Other remarkable species are Oreonetides quadridentatus (Wunderlich, 1972), to date known from only ten other localities in Germany, Coelotes atropos (Walckenaer, 1830), Gibbaranea omoeda (Thorell, 1870) and Robertus scoticus Jackson, 1914.