Leviana gen. nov.

Type species.

Epeira dimidiata L. Koch, 1871 (designated here).

Etymology.

The generic name honours the late Herbert Levi (1921-2014) for his contribution to araneid taxonomy and systematics. The gender of the genus-group name is feminine.

Diagnosis.

The following morphological and behavioural synapomorphies unequivocally diagnose Leviana gen. nov. from other genera of the Araneidae, specifically those of the putative backobourkiines ( Acroaspis Karsch, 1878; Backobourkia Framenau, Dupérré, Blackledge & Vink, 2010; Carepalxis L. Koch, 1872, Hortophora Framenau & Castanheira, 2021; Lariniophora Framenau, 2011; Novakiella Court & Foster, 1993; Plebs Joseph & Framenau, 2012; Salsa Framenau & Castanheira, 2022, Socca Framenau, Castanheira & Vink, 2022): abdomen without humeral or posterior dorsal humps; basal arch of the median apophysis of the male pedipalp internally with basally directed spine (e.g. Figs 3C, 4A, 7C, 12C, 15C); female epigyne generally wider than long, ovoid atrium, scape broad to triangular without terminal pocket, but broken off in most specimens (e.g. Figs 3E, 8C, 11C, 16C, D); incorporation of a curled leaf as retreat into the periphery of an open V-section in the web (Fig. 1A) (but details on web-building in some species unknown).

Members of the genus Leviana gen. nov. superficially resemble those of the leaf-curling genera Artifex Kallal & Hormiga, 2018, Deliochus Simon, 1894 and Phonognatha, particularly in the cylindrical shape of the abdomen and the lack of abdominal humps. However, this is likely a reflection of the leaf-curling behaviour which appears to favour such body shape. Artifex, Deliochus and Phonognatha belong to the araneid subfamily Phonognathinae (as Zygiellinae in Kallal and Hormiga (2018)) or Phonognathidae (sensu Kuntner et al. 2019), whereas Leviana gen. nov. morphology is consistent with the backobourkiines (sensu Scharff et al. 2020).

Description.

Small to medium-sized (total length males ca. 2.0-7.0, females 2.5-10.0 mm) orb-weaving spiders, with males slightly smaller than females. This difference in the size of sexes can be considered as very moderate sexual size dimorphism (Kuntner and Coddington 2020). Carapace (e.g. Figs 7A, 8A, 10A, 11A, 17A, 18A) longer than wide, pear-shaped; centre of cephalic region protruding more in males than in females; fovea poorly demarcated both in males and females forming a shallow pit; colouration brown in variable shades, sometimes with darker lateral flanks and cephalic area generally lighter; weak white pubescence both in males and females, particularly in the cephalic area. Eyes: anterior median eyes largest, their row wider than that of posterior median eyes; row of posterior eyes slightly recurved; lateral eyes almost touching and separated by more than their diameter from posterior median eyes; lateral eye groups elevated, a small horn of this elevation protrudes anteriorly. Sternum longer than wide. Labium wider than long, subtriangular, front end bulging and white. Maxillae with large lateral tooth present in males. Chelicerae with 4 (rarely 3) promarginal teeth, 3 (rarely 2) retromarginal teeth, Legs: leg formula I> II> IV> III; tibiae I and II in males strong in some species with more distinct spines, specifically prolaterally (e.g. Figs 12A, B, 15A, B, 17A, B); coxae I of male with hook and femora II with opposing groove. Abdomen longer than wide; ovoid to cylindrical, slightly dorsoventrally flattened in some species (e.g., Figs 7A, 8A, 12A, 13A, 17A, 18A); booklung covers with grooves; dorsum of abdomen uniform with some dark or light markings (Figs 7A, 8A, 10A, 11A) or with more or less distinct Leviana folium pattern (e.g., Figs 12A, 13A, 15A, 16A); ventral abdomen centrally light to dark grey, generally with lateral irregular guanine bands (e.g., Figs 8B, 10B, 13B, 18B).

Spinnerets (based on female L. folium sp. nov. see Fig. 2A-D) (nomenclature and abbreviations after Coddington (1989)): Anterior lateral spinnerets (ALS) with large field of piriform gland spigots (PI) (piriform spigots with normal bases), a major ampullate gland spigot (MAP) and a nubbin (nu) (Fig. 2B); posterior lateral spinnerets (PLS) with large field of aciniform gland spigots (AC), two aggregate gland spigots (AG) with a flagelliform gland spigot (FL) in between and a cylindriform gland spigot (CY) mesally (Fig. 2C); posterior median spinneret with large field of aciniform gland spigots, a central cylindriform gland spigot and a posterior minor ampullate gland spigot (mAP) (Fig. 2D).

Male pedipalp femora with tubercle; patellae with a single strong macroseta (e.g., Fig. 4A, 5B, 7C, D). Paracymbium present, simple and rounded (Figs 4B, 5C, 7D). Cymbium narrow. Conductor entire and prominent, heavily sclerotised, with a number of lobes and processes (e.g. Figs 3A, 4A, 5B); basal conductor lobe present (e.g. Figs 3A, 4A, 5B). Median apophysis transverse, tip pointing apically and either broadly lobed (Figs 3A, 4A, 5B, 7C, 10C, 12C) or more or less tapering (Figs 15C, 17C), basal arch internally with large spine (Figs 3A, C, 4A, 7C, 12C). Embolic division with radix, stipes, terminal apophysis and embolus (e.g., Figs 3A, B, 5A-C). Radix elongated, partially sclerotised. Stipes a thin, sometimes translucent but prominent lamella (e.g. Figs 3A, D, 4A, 5A, 7A). Terminal apophysis fleshy, elongated and terminating in two lobes or one lobe and spine (Figs 3A, D, 4A, B, 17C). Embolus short, curved and heavily sclerotised (e.g. Fig. 3A, D); tip of the embolus uncapped.

Epigyne ovoid, generally wider than long (e.g. Figs 3E, F, 8C, F, 11C, F), scape approximately as long as epigyne, thin, broadly lipped or triangular (Figs 8C, 11C, 13C, 16C)), but broken off in most specimens (e.g., Figs 3E, 8F, 13F, 16F, 18C); spermathecae ovoid, fertilization ducts slightly curved an attaching laterally at atrium (Fig. 6A, B).

Composition.

Leviana dimidiata (L. Koch, 1871) comb. nov.; L. cincinnata sp. nov.; L. folium sp. nov., L. minima sp. nov.; L. mulieraria (Keyserling, 1887).

Distribution.

Tropical, east and south-eastern Australia (Australian Capital Territory (inferred), New South Wales, Northern Territory, Queensland, Victoria, Western Australia) (Figs 9, 14).