Artifex, Kallal & Hormiga, 2018

ARTIFEX View in CoL GEN. NOV.

Type species: Epeira melanopyga Koch, 1871 .

Diagnosis: Artifex gen. nov. can be distinguished from other zygielline araneids based on the following combination of characters: a brown ring and crescent shapes on the dorsum of the abdomen ( Fig. 40A), wider posterior abdment ( Figs 40A, 44A) usually surrounding apodemes, on a pale guanocyte field in both sexes and a rugose area on the posterior margin of the ALS. Phonognatha has ovate or circular markings and Deliochus has stripes, and both genera have abdomens that are globose or with parallel sides. Males have a somewhat elongated conductor with a process pointing apically near centre of palp, a translucent membrane wrapping the conductor mesally ( Fig. 41B, E–I) absent in other zygiellines, embolus with sclerotized shaft and sperm duct separated by pars pendula ( Fig. 41B) not present in Phonognatha , convering about midway, with minute hooks on both, and the absence of median apophysis ( Fig. 10C). Females can be identified based on the epigynum with two wide ventral copulatory openings without a scape separated by a sclerotized carina or septum and broad, somewhat sclerotized copulatory duct. Females can be distinguished from Phonognatha and Deliochus by the wider posterior abdomen and broad copulatory openings ( Figs 39D, 43D). Males have a membranous layer of the conductor ( Fig. 40E) absent in related genera.

Description

Female: Total length 9.45–14.11. Carapace 4.87–6.01 long, 3.12–4.30 wide, 1.41–2.16 high, yellowish brown to reddish brown in colour, with pars cephalica and carapace margins darker than pars thoracica. AMEs on small prominence; lateral eyes juxtaposed, paired on a small prominences; AME diameter 0.25–0.44; AME interdistance slightly wider than AME diameter; AME– PME distance c. AME diameter. Clypeus c. 1/2–3/4 AME diameter. Paturon coloured as pars cephalica, with 3 prolateral and 3 retrolateral teeth. Leg formula 1243, coloured as cephalothorax, or slightly lighter; femur I sigmoid. Abdomen 5.94–9.62 long, 4.18–7.15 wide, 3.03–7.02 high; light brown with pale guanocytes; 1–5 dark brown markings, often with dark brown posterior; ventral side two longitudinal stripes from epigastric furrow to spinning field. Spinning field typical of araneoids, with the following exceptions common to zygielline (and some nephiline) araneids: a rugose area on posterior rim of ALS making a notch in the piriform spigot field and one flagelliform spigot of triad closer to a cylindrical gland spigot than aggregate gland spigots. Epigynum with large, ventral-facing copulatory openings separated by a sclerotized septum; copulatory duct broad and somewhat sclerotized, curling ventrally to reach spermathecae; fertilization ducts emerging dorsal and posterior from spermathecae. Copulatory duct frequently plugged with minutely serrated emboli.

Male: Total length 4.46–6.91. Carapace 2.28–3.90 long, 1.45–2.39 wide, 0.77–1.12 high, yellowish brown to reddish brown in colour, with pars cephalica and lateral edges of carapace darker than pars thoracica. AMEs on small prominence; eye arrangement as in female; AME diameter 0.16–0.26; AME interdistance slightly wider than AME diameter; AME–PME distance c. AME diameter. Clypeus c. 1/2 AME diameter. Chelicerae coloured as pars cephalica, with 3 prolateral and 2 retrolateral teeth. Legs formula 1243, coloured as cephalothorax, or slightly lighter; femur I sigmoid. Abdomen 2.72–3.50 long, 1.68–2.40 wide, 1.71–2.41 high; 1–5 dark brown markings, often with dark brown posterior; ventral side two longitudinal stripes from epigastric furrow to spinning field. Spinning field similar to female. Pedipalp tibia approximately half the length of cymbium; cymbium slightly elongated, with broad, integral paracymbium; tegulum and subtegulum rotated dorsally; membrane connecting embolic division with tegulum near embolic base; embolus with sclerotized shaft and sperm duct separated by pars pendula, then converging at about midway, with small barbs near point of convergence; conductor coiled with an embolic groove, covered ectally with translucent membrane covering mid-conductor process.

Composition: Artifex gen. nov. is composed of two species, A. melanopyga ( Koch, 1871) comb. nov. and A. joannae ( Berland, 1924) comb. nov.

Natural history: Artifex gen. nov. is confined to tropical regions of Australia and New Caledonia. Like Deliochus , it is characterized by female-biased sexual size dimorphism. Pedipalps with missing bulbs and plugged copulatory ducts are common.

Phylogenetics: The monophyly of Artifex gen. nov. is supported by the putative synapomorphies of a wide posterior abdomen extending past spinnerets, wide spermathecae separation, and ring-like zygielline dorsal markings.

Distribution: Known from Queensland and New South Wales, Australia, and New Caledonia ( Fig. 42).

Etymology: The genus name is derived from the Latin word ars (craft or art) and the suffix - fex (maker), meaning a skilled crafter. The name refers to the use of a leaf as a retreat by the members of this genus. The genus is feminine in gender.