Taczanowskia yasuni, Díaz-Guevara & Macías-Tulcán & Galvis, 2024

Díaz-Guevara, David R., Macías-Tulcán, Mauricio & Galvis, William, 2024, Taczanowskia yasuni new species: A new enigmatic species of spider (Araneidae) from the Ecuadorian Amazon canopy, Zootaxa 5397 (2), pp. 295-300 : 296-297

Taczanowskia yasuni new species

( Figures 1 –4)

Type: ♀ holotype from ECUADOR, Orellana: Reserva Étnica Waorani, Onkone Gare Biological Station , 247 m, 0.65714°N, 76.4555°W, 18 October 2005, Col. T. Erwin, M. Pimienta, A. Troya & M. Santacruz ( MECN-Ar 411 ) .

Etymology: The specific epithet is a noun in apposition taken from the type locality, and honors Ecuadorian people who remain in resistance to the threats against the Yasuní National Park and its Amazonian ecosystems.

Diagnosis: The female of T. yasuni n. sp. differs from all other species in the genus by having an epigynum with a strong curvature on medial length in lateral view ( Fig. 1E ), a thickened distal region on ventral view ( Figs. 1D , 2D ) and a opisthosoma clearly longer than wide with a widening in the middle without lobes ( Figs. 1A, 1B , 2A, 2B ) (vs opisthosoma widest at middle with two tubercles in T. onowoka Jordán, Domínguez-Trujillo & Cisneros-Heredia, 2021 and opisthosoma widest near posterior end and with side lobes in T. trilobata Simon, 1897 ( Levi, 1996: fig. 20); by the absence of dorsal tubercles on the opisthosoma (vs numerous dorsal tubercles in T. gustavoi, Ibarra-Núñez, 2013 ( Ibarra-Núñez, 2013: figs. 1–3); three pairs of dorsal tubercles in T. sextuberculata Keyserling, 1892 ( Levi, 1996: fig. 12); and one pair of dorsal tubercles in T. striata Keyserling, 1879 ( Levi, 1996: fig. 16), T. onowoka , Jordán et al. 2021: figs. 6A–D, and T. mirabilis, Levi, 1996 : fig. 8). In addition, females of T. yasuni n. sp. are similar to those of T. gustavoi in having femora III with a ventral row of teeth, but differ from them in having a femora IV with a ventral medial spine and opisthosoma clearly longer than wide (vs femora IV without such spine and opisthosoma almost circular in dorsal view in T. gustavoi ). The remaining species in the genus do not have a row of teeth present in the ventral side of femora III (except in T. gustavoi , which differs from T. yasuni n. sp. by characters described above).

Female (holotype): Total length 5.13; carapace 1.88 long, 1.89 maximum wide in thoracic region, 0.63 wide behind PLE. AME not completely rounded ( Fig. 1A ). AME longest length 0.18, shortest length of AME 0.15; ALE diameter 0.07; PME diameter 0.11; PLE diameter 0.07. Eye interdistances: AME-AME 0.16; AME-ALE 0.09; AME-PME 0.10; PME-PLE 0.14; PME-PME 0.16. Ocular quadrangle wider behind as in front; clypeus height 0.2. Leg measurements (leg number: femur, patella, tibia, metatarsus, tarsus): I: 2.85, 1.16, 1.74, 1.40, 0.50; II: 2.72, 1.10, 1.72, 1.30, 0.51; III: 1.55, 0.76, 0.98, 0.78, 0.42; IV: 1.98, 0.78, 1.33, 0.95, 0.38. Leg I with a ventral row of 28 spines in femur ( Figs. 2F, 2G ), leg II with 27 spines ( Figs. 2F, 2H ), leg III with 11 spines, and leg IV with only one medial spine on ventral side. Coloration, prosoma with black borders, cephalon orange with some scattered black irregular marks, radiating towards sides; thoracic area with the same pattern, with four clearer patches on the medial region (two on cephalic area and two more on lateral sides), with a sub-quadrangular black mark in the medial region. Carapace surface covered by long sparse black and creamy setae, especially on black marks and the four medial clearer patches. Cephalon much narrower than thoracic area ( Figs. 1B , 2B ). Chelicerae and endites creamy-white with some scattered black tiny dots. Labium and sternum creamy-yellowish with an irregular pattern of brown, same as coxae I–IV. Femora I–II brown with some proximal creamy-yellowish irregular marks, thicker than those of femora III–IV. Patellae I–II, tibiae I–II creamy-yellowish with some dark brown irregular marks, especially on the prolateral side. Femora III–IV and palps creamy-yellowish with some scattered brown irregular marks. Tarsi-metatarsi I–II, patellae-tarsi III–IV yellowish ( Figs. 1B , 2B–C ). All legs covered by whitish setae. Chelicerae with three promarginal teeth and without teeth on retromargin; sternum shield-shaped, longer than wide, widest at coxae II, rounded in the posterior side between coxae IV. Dorsum of femora I granulated and with black pigment ( Fig. 2B ); retrolateral claw of the first two pairs of legs about twice as long as prolateral claw ( Figs. 1A, 1F , 2B , 3E ). Opisthosoma: overhanging near half of carapace, longer than wide in dorsal view, completely smooth and without any hump or bumps ( Figs. 1A–B , 2A–B ). Dorsum dark brown with few scattered creamy irregular marks, with a paired longitudinal medial line of darker spots ( Fig. 1B ). Ventral side of the abdomen is creamy ( Fig. 1C ). Lateral sides covered with some creamy setae. epigynum similar in length to T. striata (see Levi, 1996: 189), but it has a strong curvature on medial length in lateral view ( Fig. 1E ) and thickened distal region on ventral view ( Figs. 1D , 2D ).

Male: Unknown.

Distribution and Comments: This species is only known from by a single specimen from northeastern Ecuador (Orellana province, Yasuní National Park; Figs. 3 , 4). collected by canopy fogging, in a lowland Amazonian ecosystem. We confirm the hypothesis proposed by Ibarra-Nuñez (2013) about the presence of the spider genus Taczanowskia in the canopy, however, there was not enough evidence to justify that T. gustavoi Ibarra-Nuñez, 2013 inhabited it. On the other hand, we can prove that this is the first confirmed species that inhabits the canopy due to the methodology used in the collection of T. Yasuni .

Figures

FIGURE 1. Taczanowskia yasuni n. sp. A, Female habitus, frontal view. B, same, dorsal view. C, same, ventral view. D, epigynum, ventral view. E, same, lateral view. F Leg II, lateral view.

FIGURE 2. Taczanowskia yasuni n. sp. A, female habitus, frontal view. B, same, dorsal view. C, same, ventral view. D, epigynum, ventral view. E, leg II, dorsal view. F, right legs, ventral view showing the row of spines G, left femur I, lateral view. H, left femur II, lateral view. Scale bars A, B, C, F, G, H, 1 mm; D, E, 0.5 mm.

FIGURE 3. Known distribution of the genus Taczanowskia (Araneidae) in Ecuador. Known distribution of the genus Taczanowskia (Araneidae) in the New World.