Attaleachernes spelaeus, Laibe & Prado & Ferreira, 2025

Laibe, Luciana, Prado, Guilherme C. & Ferreira, Rodrigo L., 2025, Looks can deceive: a troglomorphic but not troglobitic Attaleachernes species (Pseudoscorpiones: Chernetidae) from the eastern Amazon, Zootaxa 5716 (2), pp. 245-256 : 247-254

Attaleachernes spelaeus sp. nov.

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Material examined. Holotype: male ( ISLA 39675), preserved in ethanol: Curionópolis , Pará, Brazil, Cave SL _ 0190 ( 6°0'9.55"S, 49°36'58.33"W), November 2–15, 2016, collected by Spelayon Consultoria. Paratypes: four males and four nymphs (two deutonymphs and two tritonymphs), Curionópolis, Pará, Brazil, Cave SL_0190, same date and collector as holotype; two males ( IBSP 9658 ), preserved in ethanol: São Félix do Xingu , Pará , Brazil, Cave SFX_0014 ( 6°25'53.76"S, 51°50'49.92"W), November 01, 2018, collected by Ativo Ambiental LTDA ; one male, preserved in ethanol: Parauapebas , Pará, Brazil, Cave N 1_108 ( 6°0'44.62"S 50°18'52.52"W), October 04, 2024, collected by Ativo Ambiental LTDA .

Etymology. The specific epithet, spelaeus , is derived from the Greek “spēlaion,” meaning “cave.” This name refers to the subterranean environment where the new species was discovered.

Diagnosis. Attaleachernes spelaeus sp. nov. differs from A. thaleri by the following combination of characters: absence of a median mark on tergite I ( A. thaleri with a median mark on tergite I); presence of five setae on the anterior margin of the carapace ( A. thaleri with six setae on the anterior margin of the carapace); all tergites divided ( A. thaleri with tergites I and XI undivided); tergites I–IV with 6–11 setae, and subsequent ones with 13–16 setae on the posterior margin ( A. thaleri with 5–6 setae on tergites I–IV and subsequent ones with 7–8 setae); tergite XI with 10–12 setae and presence of two tactile setae ( A. thaleri with 13–15 setae and lacking tactile setae); pedipalp femur lacking sclerotization and darkened zones (pedipalp femur of A. thaleri with two darker zones on the inner side of the femur); pedipalp patella 9.1–9.8 times longer than deep ( A. thaleri patella: 7.0–8.6 times longer than deep); pedipalp trochanter with a medial posterior protuberance ( A. thaleri lacks the protuberance); chela without pedicel 8.5–9.6 times longer than deep ( A. thaleri chelae 6.8–7.5 times longer than deep); trichobothria esb, isb, eb, ib in the proximal half of the fixed chelal finger (in A. thaleri both et and it are located distally on the finger); est and ist close together in the medial portion of the fixed chelal finger (in A. thaleri isb [formally ist; see Harvey 1994] clearly distal to est, which is located at the basal portion of the fixed chelal finger); et distally isolated from it (in A. thaleri , et close to it, both at tip of fixed finger). Leg I tarsus 4.1–4.6 times longer than deep (leg I tarsus of A. thaleri 5.1–6.2 times longer than deep).

Description. Male adult ( Figs 2A , 5D , 6F ). Body pale orange-brown, pedipalps darker, chelicerae translucent. Body granulated and adorned with clavate, simple, and dentate vestitural setae.

Carapace. ( Fig. 3D ). 1.00–1.15 times longer than deep, strongly granulated, with ocular spots; lateral sides of the median transverse furrow darker, two deep furrows, subbasal furrow clearly closer to the posterior margin than to the median furrow; all setae short and clavate, 5 setae on the anterior margin, 12–16 setae (some in a discal position) on the posterior margin ( Fig. 3D ).

Chelicera. ( Figs 3F , 5C ). Hand with 5–6 setae, bs’ and bs” apically dentate ( Fig. 5C ); fixed finger with 3 larger distal teeth and 3 small subapical teeth, movable finger with a bicuspid subapical lobe; subgaleal seta smooth, reaching beyond tip of galea, galea robust and smooth; rallum with 3 simple blades, the anterior one dentated; external serrula with 12–16 blades.

Tergites. All tergites divided, setae clavate and small; chaetotaxy of tergites I–XI: 6–11: 7–12: 12–15: 11–21: 12–21: 23–24: 24–26: 18–24: 16–23: 18–23: 11–12.

Coxae. Palpal: coxal lobe with 18 setae, two marginal, 15 discal setae and one anterior microseta, tegument granulated on the lateral and anterior surfaces. Pedal: coxal chaetotaxy: 9–13: 9–14: 10–15: 10–15.

Genital operculum of male. 16 setae in two semicircular series.

Genital operculum of female: Spermatheca unknown.

Pedipalp. ( Figs 4A–E , 6A–F ). Simple and clavate setae, strongly granulated; trochanter with a protuberance in the posterior medial region, 2.11–2.49 times longer than deep; femur 10.40–11.72 times longer than deep; patella 9.12–9.81 times longer than deep; chela 8.49–9.57 times longer than deep; movable chelal finger 8.13–9.77 times longer than deep. Fixed chelal finger with 44–52 small and sharp teeth and 5–7 internal accessory teeth, movable finger with 41–55 small and sharp teeth. Venom apparatus located in movable finger between the trichobothria t and st. Fixed chelal finger trichobothria esb, isb, eb, ib in the proximal half of the fixed chelal finger; est and ist close together in the medial portion of the chelae; only et at the tip of the fixed chela finger isolated from it ( Figs 4C–D , 6A–B ).

Leg I. ( Figs 3B , 5B ) Trochanter 1.14–1.47 times longer than deep; femur 1.15–1.54 times longer than deep; patella 1.96–2.07 times longer than deep; tibia 3.43–3.59 times longer than deep; tarsus 4.10–4.57 times longer than deep. A pair of long pseudotactile setae at the tip of the tarsus; clavate setae present on the antiaxial face and smooth setae on the paraxial face; claws smooth and longer than the undivided arolium.

Leg IV. ( Figs 3C , 5A ). Trochanter 1.51–1.80 times longer than deep; femur + patella 2.62–3.02 times longer than deep; tibia 4.04–4.67 times longer than deep; tarsus 4.48–4.87 times longer than deep. A pair of long pseudotactile setae at the tip of the tarsus; clavate setae present on the antiaxial face and smooth setae on the paraxial region; claws smooth and longer than the undivided arolium.

Measurements. (length/width or depth in mm; ratios in parentheses, calculated with three significant digits). Range for the male holotype and male paratypes. Body length. 1.57–1.75/0.73–0.86 (2.03–2.26). Carapace 0.60– 0.62/0.50–0.59 (1.01–1.24). Palps: Trochanter 0.30–0.41/0.16–0.18 (2.10–2.49), femur 0.71–1.35/0.11–0.12 (10.40–11.72), patella 0.73–1.3/0.12–0.13 (9.12–9.81), chela 1.09–1.21/0.12–0.14 (8.46–9.77), movable finger 0.49–0.52/0.05–0.06 (8.13–9.77). Leg I: Trochanter 0.11–0.16/0.10–0.11 (1.14–1.47), femur 0.14–0.16/0.10–0.14 (1.10–1.60), patella 0.25–0.26/0.12–0.13 (1.96–2.07), tibia 0.25–0.26/0.07 (3.43–3.59), tarsus 0.21–0.22/0.05 (4.10–4.57). Leg IV: Trochanter 0.14–0.17/0.09–0.10 (1.51–1.80), femur 0.13–0.15/0.11 (1.18–1.36), patella 0.28– 0.38/0.15–0.16 (1.91–2.40), tibia 0.33–0.38/0.08 (4.04–4.67), tarsus 0.25–0.26/0.05–0.06 (4.48–4.87).

Tritonymph. Pale body, mostly depigmented or beige. Clavate setae, projected anteriorly on the carapace and posteriorly on the opisthosoma.

Chelicera. Five setae on the palm, bs’ and bs” apically dentate, galea with three apical branches.

Palp. Trochanter: 1.70–1.84 times longer than deep; femur 4.41–4.89 times longer than deep; patella 4.41–4.62 times longer than deep; chela 4.72–5.11 times longer than deep and 2.03 times longer than the movable finger.

Leg I. Trochanter 1.19–1.36 times longer than deep; femur 1.12 times longer than deep; patella 1.54–1.74 times longer than deep; tibia 2.44 times longer than deep; tarsus 3.16–3.58 times longer than deep.

Leg IV. Trochanter 1.67–1.79 times longer than deep; femur + patella 2.34–2.40 times longer than deep; tibia 3.48–3.53 times longer than deep; tarsus 2.83–3.48 times longer than deep.

Measurements. Body length 1.14–1.19/0.60–0.61 (1.86–1.98). Carapace 0.44/0.44–0.51 (1.10–1.18). Palps: trochanter 0.20–0.22/0.11–0.13 (1.70–1.84); femur 0.38–0.43/0.09 (4.41–4.89); patella 0.41–0.44/0.09–0.10 (4.39– 4.60); chela 0.56/0.11–0.12 (4.72–5.11), movable finger length 0.27–0.28/0.05–0.06 (4.81–5.89). Leg I: trochanter 0.08–0.09/0.07 (1.19–1.36); femur 0.08–0.09/0.07–0.08 (1.12); patella 0.13–0.14/0.08–0.09 (1.54–1.74); tibia 0.13–0.15/0.05–0.06 (2.44); tarsus 0.14/0.04 (3.16–3.58). Leg IV: trochanter 0.10–0.12/0.06–0.06 (1.67–1.79); femur + patella 0.26/0.11 (2.34–2.40); tibia 0.21–0.23/0.06 (3.48–3.53); tarsus 0.15–0.16/0.04–0.05 (2.83–3.48).

Figures

FIGURE 2. Attaleachernes spelaeus sp. nov., holotype (ISLA 39675) habitus, dorsal view. Scale bar: A (1.0 mm).

FIGURE 3. Attaleachernes spelaeus sp. nov., male holotype (ISLA 39675) A left chelicera B Leg I of male paratype C Leg IV of male paratype D Carapace of male holotype (ISLA 39675) E Abdomen vestitural setae of male paratype. Scale bars: 0.1 mm (A, E), 0.2 mm (B–D)

FIGURE 4. Attaleachernes spelaeus sp. nov. male paratype (IBSP 9658) A Right chela, paraxial view B Right chela, ventral view C Right chela, paraxial view, showing arrangement of trichobothria D Right chela, antiaxial view, showing arrangement of trichobothria E Right pedipalp, ventral view. Scale bars: 0.2 (A–D) 0.5 (E).

FIGURE 5. Attaleachernes spelaeus sp. nov. male paratype (IBSP 9658) A Left leg IV, antiaxial view B Left leg I, antiaxial view C Left Chelicera, dorsal view D Abdomen vestitural setae.

FIGURE 6. Attaleachernes spelaeus sp. nov. male paratypes (IBSP 9658) A Left chela, paraxial view B Left chela, antiaxial view C Right pedipalp, dorsal view D Right chela, ventral view E Left chela, paraxial view F Male paratype (IBSP 9658) general aspect, showing appendices proportion, ventral view.