FNZ 44 - Lycosidae (Arachnida: Araneae) - Introduction
Vink, CJ 2002. Lycosidae (Arachnida: Araneae). Fauna of New Zealand 44, 94 pages.
( ISSN 0111-5383 (print), ; no. 44. ISBN 0-478-09347-0 (print), ). Published 23 Dec 2002
Spiders of the family Lycosidae Sundevall, 1833 (wolf spiders) are found worldwide and constitute the fourth largest spider family with 2253 described species in 100 genera (Platnick 2002). The monophyly of the Lycosidae is supported by four characters: eye arrangement, absence of a retrolateral tibial apophysis on the male pedipalp, egg sac carried on spinnerets of females, and young carried on specialised setae on the dorsal surface of the mother's abdomen (Dondale 1986, Griswold 1993).
The eyes are in three rows (see Figs 3-5); the anterior row consists of four small eyes, the eyes in the middle row (formed by the two posterior median eyes), and in the posterior row (formed by the two posterior lateral eyes) are much larger. The posterior median eyes and the posterior lateral eyes have the strongest visual acuity (Rovner 1993). The anterior lateral, posterior median, and posterior lateral eyes have a layer of light-reflecting cells called the grate-shaped tapetum (Homann 1971). Presence of the grate-shaped tapetum is a synapomorphy for the superfamily Lycosoidea (Griswold 1993). Within the Lycosoidea, both Pisauridae Simon, 1890 and Trechaleidae Simon, 1890 have eye arrangements that are similar to lycosids, but the posterior median and the posterior lateral eyes are not as enlarged nor are the eye rows that they form as strongly recurved as those of Lycosidae.
Unlike closely related spider families (see Griswold 1993), Lycosidae lack a retrolateral tibial apophysis (RTA). The loss of this structure is believed to be the derived character state (Dondale 1986, Griswold 1993). Males of some species in the subfamily Venoniinae Lehtinen & Hippa, 1979 possess a tibial apophysis that is small, weak, and situated near the base of the tibia on the ventral surface (Lehtinen & Hippa 1979, Hippa & Lehtinen 1983). The location and nature of this apophysis suggests it is not homologous with the RTA found in related families (Dondale 1986).
All species of the Lycosidae carry their spherical egg sacs on spinnerets. Trechaleidae, a possible sister family, also carry egg sacs in this way but their egg sacs are hemispherical (van Berkum 1982, Carico 1993). In Lycosidae, active transport of young (see Fig. 98) is made possible by special setae to which the young cling (Rovner et al. 1973), while in Trechaleidae young are carried on the empty egg sac (Carico 1993).
Like all spiders, lycosids are predators and their main prey is arthropods, mostly insects (Stratton 1985, Nentwig 1987). Apart from some extralimital genera (Anomalomma Simon, 1890, Hippasa Simon, 1885, Venonia Thorell, 1894), lycosids do not build a web for prey capture and are sit-and-wait predators (Kronk & Riechert 1979). Adult size in lycosids is extremely variable (e.g., Miyashita 1968, Workman 1979, Uetz et al. 1992). Lycosid life cycles can extend over 1 (e.g., Framenau et al. 2002), 2 (e.g., Framenau et al. 1996), or 3 years (e.g., Humphreys 1976, Workman 1979), and Pardosa glacialis (Thorell, 1872) may live up to 6 years (Leech 1966). Within a species, life cycle length and synchrony may vary with altitude and latitude (e.g., Edgar 1971, Workman 1979). New Zealand lycosid adults occur in greatest numbers from late spring to late summer (Martin 1983, pers. obs.) and females are usually seen with egg sacs in late spring/early summer and in late summer/early autumn (pers. obs.).
Early instar lycosids disperse by ballooning on long buoyant strands of silk (Richter 1970, Greenstone 1982, Greenstone et al. 1987, pers. obs.), and can travel hundreds of kilometres. As a result, lycosid species are often not restricted by geographic boundaries but are often confined to a particular habitat (e.g., McKay 1974) and, despite their wide distribution, can be restricted to local areas of suitable habitat (e.g., Halloran et al. 2000). Lycosids are found in a wide range of habitats but are most common in open country. The majority of studies examining the role of lycosids in ecosystems have focused on agroecosystems. Within a given habitat, lycosids are numerically abundant predators, e.g., up to 76/m2 (Workman 1978) and, in New Zealand, they have been found to be among the numerically dominant arthropod predators in agroecosystems (Martin 1983, Sivasubramaniam et al. 1997, Topping & Lövei 1997, Hodge & Vink 2000). Because of its abundance in agroecosystems, Anoteropsis hilaris (L. Koch, 1877) has been investigated as a possible bioindicator (Hodge & Vink 2000) and biomarker (Van Erp et al. 2000, in press) for organophosphate insecticide contamination. In natural ecosystems, such as subalpine and alpine herb fields, lycosids have been reported as the dominant spider family along with Linyphiidae (Forster 1975).
While the first lycosid to be described from New Zealand was Lycosa nautica Walckenaer, 1837, this species is here excluded from the New Zealand fauna - see page 11. Most New Zealand lycosid species (23 species) were described between 1877 and 1925. Except for the description of Lycosa subantarctica Forster, 1964 (here synonymised with Anoteropsis hilaris), no further taxonomic publications on New Zealand lycosids were produced until 2001, which saw the publication of revisions of the Australasian genera Allotrochosina Roewer, 1960 (Vink 2001) and Venatrix Roewer, 1960 (Framenau & Vink 2001), both of which included species found in New Zealand. In 1996, I completed a thesis as part of a Master of Science degree (Vink 1996) on the taxonomy and systematics of a group of 10 New Zealand lycosids. This work was not published, as there were many more New Zealand species of Lycosidae that awaited description, and Australian fauna needed to be considered before correct generic placements could be made.
Most New Zealand lycosid species previously described have been placed in genera that are otherwise Holarctic. Two generic names in particular, Lycosa Latreille, 1804 and Pardosa C. L. Koch, 1847, have been frequently used in New Zealand and elsewhere as convenient genera in which to "dump" new lycosid species. Lycosa is considered to be a Mediterranean genus (Zyuzin & Logunov 2000) and Pardosa appears to be Holarctic (Vink et al. 2002). The redefinition of Lycosa (Zyuzin & Logunov 2000) and recent taxonomic work on Pardosa (Alderweireldt & Jocqué 1992, Dondale 1999, Kronestedt 1975, 1981, 1986, 1987, 1993) show they have no synapomorphic characters in common with New Zealand species. Other genera in which previously described New Zealand species have been placed include Allocosa Banks, 1900, Alopecosa Simon, 1899, Arctosa C.L. Koch, 1847, Hogna Simon, 1885, and Schizocosa Chamberlain, 1904. These genera are also considered to be Holarctic, and none of the characters in recent revisions that define them (e.g., Dondale & Redner 1978, 1979, 1983a, 1983b, 1990) are found in New Zealand species.
Vink et al. (2002) analysed DNA sequence data from a portion of the mitochondrial 12S rRNA gene of the small ribosomal subunit for several New Zealand, Australian and northern hemisphere taxa. The phylogeny they developed showed that most New Zealand species are basal in the Lycosidae and related to the Australian fauna (Text-fig. 1). Many New Zealand and Australian species do not fit in the current lycosid subfamilies (Dondale 1986, Zyuzin 1985, Alderweireldt & Jocqué 1993, Zyuzin 1993), which are based on Holarctic and African species. The two species of the derived Lycosinae (Geolycosa tongatabuensis and Venatrix goyderi) found in New Zealand appear to be more recent arrivals.
SPECIES NOT CONSIDERED PART OF THE NEW ZEALAND FAUNA
Lycosa leuckarti (Thorell, 1870). In 1985, a female specimen of this large Australian species was collected in a warehouse in Dunedin and labelled by R.R. Forster as "ex Australia?" (OMNZ). This one-off introduction is likely to have come from Australia in cargo (the label does not specify which type) and is not considered part of the fauna.
Allocosa palabunda (L. Koch, 1877). Koch's original description (Koch 1877) is based on specimens from Australia and the South Sea Islands (presumably Polynesia). I have examined many specimens of A. palabunda from Australia, and have not seen any examples from New Zealand. The erroneous New Zealand record of this species can be traced to Dalmas (1917), who included it (preceded by a question mark) in his list of New Zealand spiders. Dalmas (1917) wrote (translated from French), "The habitat given by the author [Koch] includes Australia and the South Sea Islands (Polynesia I think). The distribution could extend to New Zealand because young individuals collected at various localities seems to belong to this species". It is possible that Dalmas mistook for A. palabunda, juveniles of Geolycosa tongatabuensis (Strand), which are of a similar size, appearance, and coastal habitat. In any case, A. palabunda should not be considered part of the New Zealand fauna unless adult specimens are found, as it is difficult to identify juvenile specimens with any certainty.
Lycosa nautica Walckenaer, 1837. Walckenaer (1837) listed this species from (or as occurring in) Australia and New Zealand. His description was superficial and the type has been lost. Roewer (1955b: 1565) listed this species as "nicht zu deuten!" (cannot be determined) in his catalogue. It was listed as a nomen dubium by Platnick (2002). Walckenaer's brief description is poor even by the standards at the time of its publication. It was possible, however, to determine that the species he "described" is not one of the lycosid species found in both Australia and New Zealand. It should remain as a nomen dubium.
Pirata piraticus (Clerck, 1757). Simon (1899) recorded this Holarctic species from a specimen(s) collected by H.H. Schauinsland at French Pass (40°56'S, 173°50'E). He noted that Diplocephalus cristatus (Blackwall, 1833), a Holarctic linyphiid spider, was also found in New Zealand. Following his note, on the next page in the same publication he described Allotrochosina schauinslandi (Simon), a New Zealand endemic species that, like P. piraticus, is found in marshes and other damp habitats. P. piraticus was listed in the catalogues of New Zealand spiders of Dalmas (1917) and Parrott (1946). I have collected extensively and examined lycosid specimens from throughout New Zealand, and no specimens of P. piraticus have been found in this country since Simon's (1899) publication. There are three possibilities: 1) a European specimen of P. piraticus was accidentally included in Schauinsland's collection at the MNHN before Simon's examination; 2) P. piraticus was introduced to New Zealand by European settlers but, unlike D. cristatus, it was not successful in establishing; 3) Simon misidentified a specimen(s) of A. schauinslandi as P. piraticus, which has similar markings, size, and simple male and female genitalia. Whichever scenario is contemplated, P. piraticus is not here considered part of the New Zealand fauna.