Paccius quadridentatus Simon, 1898

Marusik, Yuri M., 2009, Redescription of Paccius quadridentatus Simon, 1898 (Araneae: Corinnidae: Trachelinae) based on the holotype, Zootaxa 1990, pp. 65-68 : 65-68

Paccius quadridentatus Simon, 1898

Figs 1–13

Paccius quadridentatus Simon, 1898: 385 (D3).

Material examined: The male holotype, with a label “19460 Paccius 4-dentatus ES im Sechellae (Brauer)” ( Fig. 11 ), Muséum National d’Histoire Naturelle, Paris.

Diagnosis: P. quadridentatus differs from its congeners by an undeveloped retrolateral cymbial extension (present in all other illustrated species and in P. madagascarensis ; Platnick, 2000: 116) and a very small, transparent (almost invisible) retrolateral tibial apophysis (well developed in all other illustrated species).

Description: Total length 4.50 (not including chelicerae). Carapace 2.25 long, 1.85 wide, 1.13 high, dark red-brown, droplet-shaped, cephalic part much wider and higher than thoracic ( Figs 1, 2 ). The entire surface covered with fine tubercles. Eyes in two almost straight rows, almost subequal in size ( Fig. 4 ). Clypeus small, about the diameter of AME. ALE spaced from the carapace margin by less than their diameter. Sternum lighter than carapace, surface covered with tubercles. Chelicerae rugous, heavily built, strongly protruding, with 4 promarginal and 4 retromarginal teeth. Labium and maxillae long, maxillae depressed along medial edges, terminal parts converging. Right maxilla S-shaped. Coxae I very long, more than two times longer than coxae III. Coxae IV spaced by less than their diameter ( Fig. 3 ). Intercoxal sclerites present. Legs pale yellow except for brownish coxae; leg surface covered with fine tubercles. Tarsi widened in terminal part, with two dentate claws placed perpendicular to the axis of the tarsus ( Fig. 6 ).

Metatarsi I and II with two ventral rows of denticles ( Fig. 5 ). Scopula present on legs I and II, or at least very weak. Metatarsi III and IV with preening comb and dense preening brush just before the comb ( Fig. 6 ).

Abdomen long, pale yellow with darker epigastric scutum encircling the pedicel. Epigastric scutum with a petiolar tube. Dorsal scutum weakly visible, coloured as rest of abdomen, almost indistinct ( Fig. 2 ). Dorsum with pair of muscle dots (sigilla) in posterior half. Venter of abdomen with weakly distinct scutum ( Fig. 3 ).

Palp as in Figs. 8–10, 12–13 . Femur and tibia very pale. Femur slightly longer than patella+tibia, with three long erect bristles ventrally. Tibia terminally expanded ( Figs 8, 10 ), retrolateral tibial apophysis small and transparent, almost invisible behind modified setae ( Fig. 9 ). Median setae large, boat-shaped. Cymbium lacking a distinct retrolateral extension. Tegulum very flat, invisible in strict retrolateral view ( Fig. 13 ). Conductor very weak and transparent, almost invisible ( Fig. 8 ).

Remarks. This species is known so far only from the holotype. While extensive collections on Seychelles have been conducted from the 1970s to the present, no Paccius specimens seem to have been collected in this Archipelago ( Saaristo, 2002 and unfinished manuscript on spiders of Seychellois spiders).

Figures

FIGURES 1 – 6. Habitus and somatic characters of Paccius quadridentatus. 1 – 3 — habitus, dorsal, lateral and ventral, respectively; 4 — prosoma, frontal; 5 — metatarsus I; 6 — metatarsus and tarsus III. Scale 1 – 4 = 0.5 mm, 5 = 0.2 mm. Abbreviations: Ds — dorsal scutum; Es — epigastric scutum; Is — intercoxal sclerite; Pb — preening brush; Pc — preening comb; Pt — petiolar tube; Vc — ventral scutum; Vd — ventral denticles; Vs — ventral scutum; Wt — widened tip of tarsus.

FIGURES 8 – 13. Male palp and label of holotype of Paccius quadridentatus. 8 — palp, ventral; 9 — tibia, retrolateral; 10 — palp after maceration in lactic acid, showing trajectory of seminal duct; 11 — original Simon’s label; 12 — palp, dorsal; 13 — palp, retrolateral, showing flat tegulum. Scale = 0.2 mm. Abbreviations: Co — conductor; Ms — median seta; Sd — seminal duct; Ta — tibial apophysis.