Cycloctenidae

Toxopsiella medialis, copyright Te Papa Tongarewa.

Belongs within: Amaurobioidea.

The Cycloctenidae, scuttling spiders, are a group of free-living hunting spiders endemic to Australasia (Jocqué & Dippenaar-Schoeman 2007).

The Cycloctenidae: unassuming in Australasia

The higher classification of spiders has long been a challenging subject. Sure, we’ve come a long way from the days of Clerck and Linnaeus, when every spider was included in the single genus Araneus or Aranea, but there remain many assemblages we find difficult to define. One such grouping is the Australasian spiders of the Cycloctenidae.

Cycloctenus sp., copyright Don Horne.

Members of the Cycloctenidae are largely ground-dwelling spiders, commonly found hunting for prey among the litter of the forest floor. They do not construct webs as snares though species of the genus Plectophanes use holes in twigs as retreats (Paquin et al. 2010). Some species are found around tussocks and scree slopes in upland habitats. Originally recognised as a subgroup of the wolf spiders of the Lycosidae, which they commonly resemble in overall habitus, the cycloctenids were separated as their own family on the basis of their distinctive eye arrangement. In genera such as Cycloctenus and Toxopsiella, the eight eyes are arranged in two strongly recurved rows with the posterior pairs of eyes larger than the anterior.

Cycloctenids were just one of a number of families of ground-hunting spiders whose relationships and composition were historically not easy to define. Recent molecular phylogenetic studies have placed the cycloctenids within a clade uniting a number such families, dubbed by Wheeler et al. (2017) as the ‘marronoid’ clade. This may just be one of biology’s most sarcastically labelled clades, as its name almost literally means ‘brown’, in reference both to its members’ typical appearance and their general morphological conservatism. These are brown spiders, living brown lives, evoking brown feelings in many who observe them.

One of the less ‘brown’ of the cycloctenids: Plectophanes sp., copyright Steve Kerr. Members of this genus have the carapace around the eyes projected forward on a turret.

Wheeler et al. (2017) identified the prior cycloctenids as forming a discrete clade within the marronoids, but also found them associated with a handful of genera (Orepukia, Pakeha and Paravoca) that had previously been included in the poorly defined families Amaurobiidae and Agelenidae. These genera do not share the distinctive cycloctenid eye arrangement but they do share their distinctive distribution, all being endemic to New Zealand. Rather than establish new nondescript families for these genera, Wheeler et al. suggested expanding the Cycloctenidae to encompass them as well. This does leave the Cycloctenidae somewhat difficult to distinguish on morphological grounds. Wheeler et al. described the cycloctenids in their new sense as “Araneomorphae with three claws, simple posterior tracheae, a complex RTA [retrolateral tibial apophysis] and a hyaline conductor on the male palp”. Though noteworthy, none of these features are unique to cycloctenids. These spiders have relatively simple lives; this is largely reflected in their simple appearance.

Systematics of Cycloctenidae

Characters (from Jocqué & Dippenaar-Schoeman 2007): Small to medium-sized araneomorph spiders; eight eyes, eyes in two strongly recurved rows with posterior eyes much larger than anterior one; three tarsal claws; claw tufts and scopulae absent; ecribellate; entelegyne.

<==Cycloctenidae [Cyclocteninae]
    |--Galliena Simon 1898JD-S07
    |--Uzakia Koçak & Kemal 2008PVD10 [=Anaua Forster 1970 (preoc.)PVD10, JD-S07]
    |    `--*U. unica (Forster 1970) [=*Anaua unica]PVD10
    |--Plectophanes Bryant 1935PVD10
    |    |--*P. frontalis Bryant 1935PVD10
    |    |--P. altus Forster 1964PVD10
    |    |--P. archeyi Forster 1964PVD10
    |    |--P. hollowayae Forster 1964PVD10
    |    `--P. pilgrimi Forster 1964PVD10
    |--Cycloctenus Koch 1878PVD10
    |    |--C. agilis Forster 1979PVD10
    |    |--C. centralis Forster 1979PVD10
    |    |--C. duplex Forster 1979PVD10
    |    |--C. fiordensis Forster 1979PVD10
    |    |--C. flaviceps Koch 1878S99
    |    |--C. fugax Goyen 1890PVD10
    |    |--C. lepidus Urquhart 1890PVD10
    |    |--C. nelsonensis Forster 1979PVD10
    |    |--C. paturau Forster 1979PVD10
    |    |--C. pulcher Urquhart 1891PVD10
    |    `--C. westlandicus Forster 1964PVD10
    `--Toxopsiella Forster 1964PVD10
         |--*T. lawrencei Forster 1964PVD10
         |--T. alpina Forster 1964PVD10
         |--T. australis Forster 1964PVD10
         |--T. centralis Forster 1964PVD10
         |--T. dugdalei Forster 1964PVD10
         |--T. horningi Forster 1979PVD10
         |--T. medialis Forster 1964PVD10
         |--T. minuta Forster 1964PVD10
         |--T. nelsonensis Forster 1979PVD10
         |--T. orientalis Forster 1964PVD10
         |--T. parrotti Forster 1964PVD10
         `--T. perplexa Forster 1964PVD10

*Type species of generic name indicated

References

[JD-S07] Jocqué, R., & A. S. Dippenaar-Schoeman. 2007. Spider Families of the World. Royal Museum for Central Africa: Tervuren (Belgium).

[PVD10] Paquin, P., C. J. Vink & N. Dupérré. 2010. Spiders of New Zealand: annotated family key and species list. Manaaki Whenua Press: Lincoln (New Zealand).

[S99] Simon, E. 1899. Ergebnisse einer Reise nach dem Pacific (Schauinsland 1896–1897). Arachnoideen. Zoologische Jahrbücher, Abteilung für Systematik, Geographie un Biologie der Thiere 12 (4): 411–437.

Wheeler, W. C., J. A. Coddington, L. M. Crowley, D. Dimitrov, P. A. Goloboff, C. E. Griswold, G. Hormiga, L. Prendini, M. J. Ramírez, P. Sierwald, L. Almeida-Silva, F. Alvarez-Padilla, M. A. Arnedo, L. R. Benavides Silva, S. P. Benjamin, J. E. Bond, C. J. Grismado, E. Hasan, M. Hedin, M. A. Izquierdo, F. M. Labarque, J. Ledford, L. Lopardo, W. P. Maddison, J. A. Miller, L. N. Piacentini, N. I. Platnick, D. Polotow, D. Silva-Dávila, N. Scharff, T. Szűts, D. Ubick, C. J. Vink, H. M. Wood & J. Zhang. 2017. The spider tree of life: phylogeny of Araneae based on target-gene analyses from an extensive taxon sampling. Cladistics 33: 574–616.

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