Porrhomma cambridgei Merrett, 1994

Růžička, Vlastimil, 2018, A review of the spider genus Porrhomma (Araneae, Linyphiidae), Zootaxa 4481 (1), pp. 1-75 : 16-18

publication ID

https://doi.org/ 10.11646/zootaxa.4481.1.1

publication LSID

lsid:zoobank.org:pub:BFC4982D-BB84-4141-BDFD-203F23CD1585

DOI

https://doi.org/10.5281/zenodo.5963971

persistent identifier

https://treatment.plazi.org/id/03C6A93B-FFD9-FFC4-FF7C-F8C587B83F93

treatment provided by

Plazi

scientific name

Porrhomma cambridgei Merrett, 1994
status

 

Porrhomma cambridgei Merrett, 1994 View in CoL

Figs. 13A–F View FIGURE 13 .

Linyphia View in CoL (?) oblonga O. Pickard-Cambridge, 1871 — O. Pickard-Cambridge (1871): p. 433 (descr. ♀); preoccupied, replaced by Merrett (1994).

Microneta oblonga — Simon (1884): p. 441. Porrhomma oblongum — F. O. Pickard-Cambridge (1894): p. 102, Pl. II, Fig. 4 View FIGURE 4 (♀, descr. ♂). considered a synonym of P. oblitum ( O. Pickard-Cambridge, 1871) View in CoL by Millidge & Locket (1952: p. 71). P. cambridgei Merrett, 1994 View in CoL — Merrett (1994): p. 318, Figs. 1–4 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 (redescr. ♀); replacement name for P. oblongum ; removed from

synonymy of P. oblitum View in CoL , contra Millidge & Locket (1952).

Material examined. CZECHIA: Bohemian Karst , Srbsko , 2 May 1999, 1 ♀, 5 July 2000, 2 ♀, leg. et coll. L. Kubcová. Liteň, 7 Mar –12 Apr 2011, 2 ♀, leg. A. Tenčík. Vápenný Podol, Podolská and Páterova Caves , 22 May – 18 Nov 2003, 1 ♀; Moravian Karst , Harbešská Cave, 15 Aug 2008, 1 ♂ 1 ♀, leg. R. Mlejnek. Horka nad Moravou, 6 Mar–13 Nov 2008, 2 Ƌ 6 ♀, leg. V. Laška & I . H. Tuf. Jenišovice-Zalažany, Mravín , 18 Apr 2014 –29 Sep 2015, 5 ♂ 6 ♀; Pardubice-Polabiny, 28 Apr–23 Sep 2015, 1 ♀, leg. V. Růžička & J . Dolanský ( IECA). Moravský Krumlov, Rokytná, 27 Apr 2002, 1 ♀, leg. V. Bryja (CVB).

Diagnosis. Small species (CW <0.60 mm), Fe I–II without dorsal spines, AP has the form of a bird head, Sshaped ascending parts of copulatory ducts. It is closely similar to P. oblitum , but it can be distinguished by depigmented body and reduced eyes ( Fig. 13A View FIGURE 13 ).

Description. ♀ (from Horka nad Moravou, Czechia, 21 Aug–2 Oct 2008). Carapace pale yellow, 0.57 mm wide, eyes reduced, PME–PME = 2.3 ( Fig. 13A View FIGURE 13 ). Abdomen pale. Fe without dorsal spines, Fe I with one prolateral spine. Ti I–II with one retrolateral spine. Tm Mt I = 0.39, Mt I/CW = 0.87. Ascending parts of the ducts are Sshaped. Spermathecae are formed behind the ascending part of the ducts ( Figs. 13C–F View FIGURE 13 ).

Ƌ (from Jenišovice-Zalažany, Mravín, Czechia, 18 Apr 2014 – 29 Sep 2015). Embolus of middle length with a narrow velum. AP has the form of a bird head ( Fig. 13B View FIGURE 13 ).

Variation. Ƌ ♀. Carapace 0.56–0.59 mm wide. Ti I sometimes with one prolateral spine. Tm Mt I = 0.39–0.41, Mt I/CW = 0.84–0.89 (n = 8) ( Růžička et al. 2011; sub P. aff. myops ).

Comments. O. Pickard-Cambridge (1871) described that the species Linyphia (?) oblonga is characterised by “eyes very small”. Based on vulva structure, Millidge & Locket (1952) synonymised this microphthalmic form with Porrhomma oblitum . Finally, Merrett (1994) removed it from synonymy with P. oblitum and revalidated it as a separate species P. cambridgei . Genitalia are indistinguishable from those of P. oblitum . The species is clearly characterised by femora I and II without dorsal spines, cephalothorax width <0.58 mm and reduced eyes. I found no intermediate form between P. cambridgei and P. oblitum .

Ecology. The species was collected on tree bark in the Bohemian Karst ( Thaler et al. 2003), in detritus in this karst region, and in conglomerate terrains in southern Moravia. Other specimens were found in grasslands ( Merrett 1994). However, the reduced eyes suggest that this species lives mainly in subterranean habitats. Růžička & Dolanský (2016) and Růžička et al. (2011, sub. P. aff. myops ) documented the occurrence of this species in sandy marlite terrain, alluvial soils and in karst terrain (unpubl.) at a depth of 35–140 cm. Finally, P. cambridgei was collected in two karst caves at a depth of 60 m.

Global distribution. Europe among southern England, northern Italy and the Czech Republic after Hänggi (1999), Zingerle (1999), Harvey et al. (2002), van Keer et al. (2016), Arachnologische Gesellschaft (2017), and this paper. See Fig. 14 View FIGURE 14 .

IECA

Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Entomology

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Linyphiidae

Genus

Porrhomma

Loc

Porrhomma cambridgei Merrett, 1994

Růžička, Vlastimil 2018
2018
Loc

P. cambridgei

Merrett 1994
1994
Loc

oblonga

O. Pickard-Cambridge 1871
1871
Loc

Microneta oblonga

O. Pickard-Cambridge 1871
1871
Loc

Linyphia

Latreille 1804
1804
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