Mysmenidae Petrunkevitch, 1928
|
publication ID |
https://doi.org/ 10.3897/zookeys.11.160 |
|
publication LSID |
lsid:zoobank.org:pub:C631A347-306E-4773-84A4-E4712329186B |
|
persistent identifier |
https://treatment.plazi.org/id/03ACB915-FF89-7403-FF4E-45FBFD9EF93F |
|
treatment provided by |
Plazi |
|
scientific name |
Mysmenidae Petrunkevitch, 1928 |
| status |
|
Family Mysmenidae Petrunkevitch, 1928 View in CoL View at ENA
Recent authors have focused on a handful of characters to define Mysmenidae : the presence of a sclerotized subdistal ventral spot ( Griswold et al. 1998: fig. 10G) on femur I (and sometimes II as well) of females (and sometimes males as well), the presence of a prolateral macroseta on male metatarsus I (Fig. 17D), and a distally twisted and notched cymbium ( Platnick and Shadab 1978b, Griswold et al. 1998, Schütt 2003). Femoral spots are not universal in mysmenids, absent from the new genus Gaoligonga and most species of Mysmenopsis Simon, 1897 ( Platnick and Shadab 1978b), which are otherwise typical mysmenids. The mysmenid cymbium is typically very complex, featuring a series of distal lobes that interact with the embolus as a functional conductor (e.g., Figs 24D View Figure 24 , 37A View Figure 37 , 40C View Figure 40 ). While this description seems to apply to most or all mysmenids (questionable in the new genus Chanea ; Fig. 49A View Figure 49 ), it has apparently contributed to some confusion, such as the misplacement of the genus Crassignatha Wunderlich, 1995 in Mysmenidae (see below). Schütt (2003) coded the two mysmenids in her phylogenetic analysis as having non-homologous male metatarsal clasping spurs based on position (apical in Microdipoena Banks, 1895 , basal in Trogloneta Simon, 1922 ). Some Maymena Gertsch, 1960 species also lack a metatarsal clasping spur ( Gertsch 1960). Some male mysmenids have prolateral macrosetae on tibia I in addition to (rarely instead of) a metatarsal macroseta (e.g., Anjouanella Baert, 1986 , Microdipoena Banks, 1895 , Mysmenella Brignoli, 1980 , Simaoa gen. n.; Fig. 34F View Figure 34 ). Nevertheless, the clasping spur on male metatarsus I, whether proximal or distal, remains a key diagnostic character for Mysmenidae . In addition, most mysmenids have a distinctive modified seta on the PLS (Figs 19F, 42F, Griswold et al. 1998: fig. 28A; absent from the kleptoparasitic Isela Griswold, 1985 , which also lacks the triplet of spigots used to make araneoid sticky silk in both sexes; Griswold et al. 1998: figs 29D, 30D). The sticky silk triplet is vestigial in some Chinese mysmenid males ( Fig. 25D View Figure 25 ) but is fully developed in some other male mysmenids ( Griswold et al. 1998: fig. 28D).
Lateral sulci are present on the carapace of several mysmenid genera and range in form from a single pore between the lateral eyes and the margin of the carapace (Fig. 17F) and a larger hole just below the lateral eyes ( Fig. 24E View Figure 24 ). Lopardo and Hormiga (2008) reported on a similar sulcus in the enigmatic genus Acrobleps Hickman, 1979 . Anapids have one or more pores, typically associated with a plate or sulcus, on the anterolateral margin of the carapace ( Platnick and Forster 1989).
The distinctive web architecture and associated behavioral characters help to define the limits of Mysmenidae . With the exception of Maymena (which builds a horizontal anapid-like orb-web) and the webless kleptoparasites, mysmenids build a threedimensional spherical web, the result of typical orb-building behavior except that radii are not restricted to a single plane ( Figs 20 View Figure 20 , 26 View Figure 26 ; Coddington 1986b, Eberhard 1987, Griswold et al. 1998: fig. 3B). Small clusters (6-9) of eggs are placed in the center of the web (Figs 21H, 26B, D, 43C).
The limits and diagnostic features of many mysmenid genera are not entirely clear. Work in progress (Lopardo, pers. comm.) with a global scope promises substantial progress soon. But for the purposes of this geographically limited work, we must rely on the existing literature. New species were placed in the genus Mysmena Simon, 1894 based on the presence of an external cymbial groove (Figs 17A, 29A), a distinct cymbial base (Figs 17B, 24C, 29B), an embolus without a switchback or process that makes approximately one spiral turn usually guided by a groove in the tegulum (Figs 17B, 29C), a cymbial tip that engages the embolus as a functional conductor ( Figs 24D View Figure 24 , 29C View Figure 29 ), and male mating claspers restricted to metatarsus I (Figs 17D, 24F, 29D). The presence of an epigynum in the form of a scape with the left and right copulatory pathways well separated also influenced species placement ( Figs 11I View Figure 11 , 21C,E), although not all Mysmena described here have a scape (Fig. 21G,I). Internal structures consist of a pair of spermathecae, copulatory ducts usually with a sclerotized portion leading to the spermathecae and a membranous atrium (copulatory ducts occasionally membranous throughout their length; Fig. 21I). Sclerotized complexes (spermathecae or spermathecae plus part of copulatory ducts) are separated by at least their width (Fig. 21G). Fertilization ducts usually arise from the posterior part of the spermathecae and curve mesally, or arise from mesal part of spermathecae. A posterior tubercle on the abdomen is present ( Fig. 27F View Figure 27 ) or absent (Fig. 15B). Also, all new Mysmena described here have femoral spots on legs I and II (sometimes indistinct in male), although the type species of Mysmena apparently has the femoral spot only on leg I ( Kraus 1967).
Chinese Maymena described here differ from the American fauna in having the palpal patella and tibia elongated ( Fig. 54A View Figure 54 ; compare to Gertsch 1960: fig. 51). Otherwise, they closely resemble typical Maymena in genital morphology, size and coloration, association with cave habitats, and web architecture. Maymena are apparently the only mysmenids with trichobothria on the palpal tibia ( Fig. 55D View Figure 55 ), a trait shared with synaphrids and theridiosomatids among the symphytognathoids.
The remaining mysmenids were all placed in new genera. Simaoa , Gaoligonga , and Chanea all have novel features, especially male sexual characters. Simaoa maku and S. bianjing are known from female only and were tentatively placed in Simaoa based on characteristics of the female genitalia shared with Simaoa species known from both sexes. Mosu is the only new mysmenid genus known from the female only. The two species clearly share similarities in genital morphologies. Another Chinese species recently described in the genus Mysmena exhibits similar morphology in the female and could be congeneric. This species, M. zhengi Lin & Li, 2008 , is known from both sexes and so could be useful for exploring the limits of this new genus.
Diagnosis. Femur I (and sometimes II as well) of females (and sometimes males as well) with a sclerotized subdistal ventral spot (sometimes absent), prolateral macroseta on metatarsus I of the male (Fig. 17D) forming a clasping spur, distally twisted and notched cymbium ( Platnick and Shadab 1978b, Griswold et al. 1998, Schütt 2003), and distinctive modified seta on the PLS (Figs 19F, 42F) characterize Mysmenidae . Not all characters are present in all species.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.