Drymusa aculicaput (Wunderlich, 2004) new combination

Magalhaes, Ivan L. F., Perez-Gonzalez, Abel, Labarque, Facundo M., Carboni, Martin, Hammel, Joerg U., Kunz, Robin, Ramirez, Martin J. & Solorzano-Kraemer, Monica M., 2022, Revision of recluse spiders (Araneae: Sicariidae: Loxosceles) preserved in Dominican amber and a total-evidence phylogeny of Scytodoidea reveal the first fossil Drymusidae, Arthropod Systematics & amp; Phylogeny 80, pp. 541-559 : 541

5.2.1. Drymusa aculicaput (Wunderlich, 2004) new combination

Figs 3 , 4 , 5

Loxosceles aculicaput Wunderlich, 2004: 703, fig. 10b-d, photo 36.

Type material.

Holotype adult male in Dominican amber, deposited in SMNG 07/36287-422, labeled F933/DB/AR/LOX/CJW, examined. No other specimens are known.

Preservation.

The spider is completely and well-preserved in an orange piece of amber. The abdomen is slightly shrunken and shriveled but no other structures are obviously deformed. The amber piece has large fissures in the portion ventral to the spider. The piece has been embedded in artificial resin. There are no syninclusions other than some pieces of unidentifiable plants and detritus.

Diagnosis.

Drymusa aculicaput comb. nov. can be distinguished from other scytodoids preserved in Dominican amber, as well as from extant congeners, by the palp with short, incrassate tibia and by the bulb with a thin, straight, needle-like embolus (Fig. 5E, G, H, J ).

Description.

Male holotype (SMNG 07/36287-422). Structure: Carapace longer than wide, narrowed and more hirsute in the cephalic region. Six eyes in three dyads separated by 2-3 diameters (Fig. 4D ). Chelicera with basal article robust (Figs 3G , 4D ); cheliceral lamina present, with broad, triangular apex; at least one promarginal tooth present. Endites not converging in front of labium; anterior margin of labium notched (Fig. 4C ). Sternum slightly longer than wider. Legs long and thin (Figs 3A , 4A ) with a few macrosetae on the prolateral face of the first femur (Fig. 3C ) and on the ventral faces of all tibiae and metatarsi. Well-developed podotarsite; third claw present (Fig. 3F ). Spinnerets in a compact group (Fig. 5B ); colulus broad (Fig. 5A ); ALS short and broad, barely longer than PLS (Figs 4D , 5C ). Palps (Fig. 5D-J ): tibia shorter than femur, incrassate; cymbium short with a small apical extension; bulb with globose, rounded base and thin, straight, needle-shaped embolus. - Measurements [mm]: Total length (excluding chelicerae and spinnerets) 2.34. Carapace length 1.15, width 0.89. Abdomen length 1.27, width 0.66. Palpal femur length 0.52. Palpal tibia length 0.24, height 0.21. Leg I: femur 2.87, patella 0.27, tibia 3.05, metatarsus 0.91, tarsus 2.25. Leg II: femur 2.74, patella 0.38, tibia 2.67, metatarsus 3.65, tarsus 0.66. Leg III: femur 2.13, patella 0.27, tibia 1.88, metatarsus 1.95, tarsus 0.72. Leg IV: femur 2.58, patella 0.33, tibia 2.67, metatarsus 2.55, tarsus 0.72.

Figures

Figure 3. Drymusa aculicaput (Wunderlich, 2004) comb. nov., holotype (SMNG 07 / 36287 - 422), photographs under light microscopy. A, B habitus, dorsolateral. C right femur I. Arrows to anterior macrosetae. D spinnerets, dorsolateral view. E, F, H right tarsi (E: III-IV, F: II, H: I), prolateral. Arrows to third claw. Note highly articulated podotarsite. G Chelicerae and palp, subdorsal view. Arrow to tip of right embolus. Scale bars: 1 mm (A), 0.5 mm (B), 0.2 mm (C), 0.1 mm (D, G), 0.05 mm (E, F, H).

Figure 4. Drymusa aculicaput (Wunderlich, 2004) comb. nov., holotype (SMNG 07 / 36287 - 422), rendered volume after image stack obtained with synchrotron radiation micro-computed tomography. A, B habitus, dorsal. C habitus, ventral. Inset showing notched labium. D clypeus, subanterior. Scale bars: 1 mm (A), 0.5 mm (B-D).

Figure 5. Drymusa aculicaput (Wunderlich, 2004) comb. nov., holotype (SMNG 07 / 36287 - 422), rendered volume after image stack obtained with synchrotron radiation micro-computed tomography. Spinnerets (A - C), left palp (D - H), and right palp (I, J). A ventral. B apical. C dorsal. D subprolateral. E retrolateral. F prolateral. G bulb and cymbium, apical. H bulb and cymbium, dorsal. I prolateral. J retrolateral. Asterisks are artifacts in the rendering. Scale bars: 0.1 mm (only A-C, F, I to scale).