Eucteniza cuixmala, Valdez-Mondragón & Jiménez, 2024

Valdez-Mondragón, Alejandro & Jiménez, Maria Luisa, 2024, On the Mexican trapdoor spiders: description of a new species of the spider genus Eucteniza Ausserer (Araneae, Mygalomorphae, Euctenizidae) from the western coast of Mexico, Zootaxa 5453 (4), pp. 538-548 : 541-545

Eucteniza cuixmala sp. nov.

urn:lsid:zoobank.org:act:168682B7-47A3-44E9-9253-B140129B00DD

Figures 1–19

Holotype. MEXICO: Jalisco: 1 ♂ holotype ( CARCIB-Ar-050 ) from Estación de Biología , Institute of Biology , UNAM Chamela-Cuixmala Biosphere Reserve , path Buho (19.4988°, -105.0404°, 65 m a.s.l.), Municipality San Patricio, 17-June-2016, A. Zaldivar, B. Garner, V. Salinas Cols., pitfall trap.

Etymology. The specific epithet is a noun in apposition in reference to the Chamela-Cuixmala Biosphere Reserve, a tropical deciduous forest on the western coast of Mexico where the type locality is located.

Diagnosis. Eucteniza cuixmala sp. nov. resembles E. relata in the leg I morphology; however, the tibia I in the new species does not have prolateral distal spines, only one distal megaspine ( Figs 13, 15 , arrows), whereas E. relata has few (4) to many prolateral distal spines (21) (Bond & Goodwin, 2013: figs 25, 26, 29). Although both species have tibia I with 2 two large, tightly grouped median-ventral megaspines on tibia I, the distal megaspine is markedly longer and wider than basal megaspine in E. cuixmala sp. nov. ( Figs 12–15 , 16 ), whereas in E. relata both megaspines have the same length and distal megaspine is slightly wider than basal one (Bond & Goodwin 2013: figs 25, 26, 29). Tibia I in the new species is wider (widest part) than in E. relata , with a ratio of 2.5X (length/ width) ( Figs 12–15 ) in E. cuixmala sp. nov., whereas in E. relata is 2.2X (Bond & Goodwin, 2013: figs 25, 26, 29). Metatarsi I in the new species has a small megaspine in median region ( Fig. 12 , arrow), which is absent in E. relata (Bond & Goodwin, 2013: figs 25, 26, 29). The legs of E. relata are more setose (Bond & Goodwin, 2013: figs 25–27) than those of E. cuixmala sp. nov. ( Figs 12–19 ). The palp tibia in the new species is slightly wider (widest part) than E. relata (2.5X in E. cuixmala sp. nov. versus 2.4X in E. relata ). Also, body coloration in the new species is pale orange ( Figs 1–19 ), whereas E. relata is dark brown (Bond & Goodwin, 2013: fig 24).

Description. Male (holotype): Specimen collected using pitfall traps, preserved and observed in 80% ethanol. Measurements: Total length (prosoma+opisthosoma) 12.40. Carapace 5.60 long, 4.70 wide (widest part). Clypeus length 0.20. Diameter of eyes: AME 0.33, ALE 0.36, PME 0.20, PLE 0.31. Labium: LBl 0.65, LBw 0.95. Sternum: STRl 3.65, STRw 3.10. Leg lengths: I: femur 5.30/ patella 2.65/ tibia 3.80/ metatarsus 3.70/ tarsus 2.50/ total 17.95; II: 4.70/ 2.50/ 3.70/ 3.50/ 2.60/ 17.00; III: 4.20/ 2.00/ 2.70/ 4.00/ 3.20/ 16.10; IV: 5.70/ 2.80/ 5.00/ 5.10/ 3.80/ 22.4. Leg formula: 4-1-2-3.

Prosoma: Carapace longer than wide, protruding anteriorly, with surface smooth, not setose, hexagonally shaped, dark yellowish in anterior part and paler posteriorly ( Figs 1, 3 ). Ocular region slightly elevated ( Figs 3 , 6 ). Foveal groove deep and procurved, U-shaped ( Fig. 3 ). AER straight, PER recurved. Largest ALE, smallest PME ( Fig. 6 ). Right PLE missing ( Fig. 6 ). Sternum longer than wide, pyriform-shaped, pale orange, setose mainly in anterior part, with sigilla visible ( Fig. 4 ). Median pair sternal sigilla large and elongate. Labium wider than long, dark orange, with long setae anteriorly, without cuspules ( Fig. 5 ). Endites long and setose, with an inconspicuous apical-prolateral conical apophysis, without cuspules ( Fig. 5 ).

Chelicerae: Promargin furrow with six large teeth, retromargin furrow with approximately 10 small denticles. Rastellum with several small spines.

Opisthosoma: Longer than wide, setose, dark gray, without pattern dorsally; lighter gray ventrally ( Figs 1, 2 , 7 ). Spinnerets beige ( Fig. 7 ). PMS small and rounded, single segment, with spigots. PLS long and conical, all three segments with spigots: basal segment length> median segment> distal segment.

Legs: Very light tarsal scopulae on all legs ( Figs 12, 13 , 17, 18 ). Tibiae, metatarsi, and tarsi with dorsal trichobothria, lacking pattern, only tarsi with slightly staggered dorsal row, variable in number. Leg patterns: Tibia I: with two large, tightly grouped median-ventral megaspines ( Figs 12–15 ) and long ventral spiniform setae in basal half; tibiae II: with one median and long megaspine and several long spiniform setae ( Fig. 17 ); metatarsi II: with two long spiniform setae ( Fig. 17 , arrows); tibiae III and IV: scattered long spiniform setae ( Fig. 18 ); metatarsi and tarsi with small scattered spiniform setae ( Fig. 18 ). Femora with long spiniform setae, more conspicuous in femora II–IV ( Figs 17, 18 ). Patellae III and IV with small spiniform setae on prolateral part, more numerous in patellae III ( Figs 19 , arrows).

Pedipalps: Articles setose. Femora pale orange, long, and cylindrical. Patellae pale orange ( Figs 8, 9 ). Tibiae pale orange, long, and cylindrical, widened in mid-section, curved and setose ventrally ( Figs 8, 9 ). Cymbium brownish and setose, without spines, but with numerous small spiniform setae ( Figs 10, 11 ). Bulb oval, located toward internal part of pedipalp ( Figs 10, 11 ). Embolus short, thin, and curved, pointing toward retrolateral part of the tibia, slightly widened apically ( Figs 11 ).

Female. Unknown.

Natural history. The specimen was collected using a pitfall trap in a tropical deciduous dry forest at 65 m a.s.l. within the Chamela-Cuixmala Biosphere Reserve, which is part of the Estación de Biología, Institute of Biology, UNAM. The trap was collocated next to the path name ‘Buho’, one of several paths within the biological research station ( Figs 20, 21 ).

Distribution. Known only from the type locality ( Fig. 22 ).

Figures

FIGURE 22. Type locality (red circle) of Eucteniza cuixmala sp. nov. in the Chamela-Cuixmala Biosphere Reserve, Jalisco, Mexico; Estación de Biología, Institute of Biology, UNAM.

FIGURES 1–4. Eucteniza cuixmala sp. nov. Male: 1–2, Habitus, dorsal and ventral views, respectively. 3, Carapace, dorsal view. 4, Prosoma, ventral view showing coxae, sternum, labium, and endites. Scale bars: 5 mm (3, 4), 10 mm (1, 2).

FIGURES 5–7. Eucteniza cuixmala sp. nov. Male: 5, Labium and endites, ventral view. 6, Ocular region. 7, Opisthosoma, ventral view, showing spinnerets. Scale bars: 1 mm (6), 2 mm (5), 5 mm (7).

FIGURES 8–11. Eucteniza cuixmala sp. nov. Male: 8–9, Left palp, prolateral and retrolateral views, respectively. 10, Left palp, ventral view. 11, Detail of the bulb and embolus, ventral view. Scale bars: 0.3 mm (11) 3 mm (8–10).

FIGURES 12–15. Eucteniza cuixmala sp. nov. Male: 12–13, Left leg I, retrolateral and prolateral views, respectively, arrows indicate small megaspine on median region of metatarsus (12) and distal megaspine on tibia (13). 14–15, Left tibia I, detail of retrolateral and prolateral views, respectively, arrow indicates distal megaspine. Scale bars: 3 mm (14, 15), 4 mm (12, 13).

FIGURES 16–19. Eucteniza cuixmala sp. nov. Male: 16, Left tibia I, ventral view, arrow indicates distal megaspine on prolateral part. 17, Left leg II, retrolateral view, arrows indicate two small megaspines on median region of metatarsus. 18, Left legs III and IV showing spination. 19, Left patellae III and IV showing small spiniform setae (arrows) on prolateral part. Scale bars: 2 mm (19), 3 mm (16, 17), 5 mm (18).

FIGURES 20–21. Habitat of Eucteniza cuixmala sp. nov. Tropical deciduous dry forest in the Chamela-Cuixmala Biosphere Reserve, Jalisco, Estación de Biología, Institute of Biology, UNAM (photos by Alejandro Valdez-Mondragón).