Pastaza roberti gen. et sp. nov.

urn:lsid:zoobank.org:act: 444A732F-F01C-4A79-B893-5F34B3B82FBF

Figs 15– 20, 29E, 30

Diagnosis

Males most resemble those of P. vegai sp. nov. but are distinguished by their palpal bulb with two large keels (Fig. 17D), one keel in the latter (Fig. 23D). Females most resemble those of P. aureliae sp. nov. but are distinguished by the internal genitalia with spermathecae separated by 2× their diameter, and on elongated stalks (Fig. 20C–E) whereas in the latter, spermathecae are closer together, separated by their diameter and on short stalks (Fig. 14C–E).

Etymology

The specific epithet is a patronym in honor of Robert Raven, for his contribution to the study of mygalomorph spiders and his support in the study of the South American fauna.

Type material

Holotype ECUADOR • ♂; Sucumbíos, Green Paradise Lodge; 0°22′47″ S, 76°09′10″ W; 231 m a.s.l.; 24 –28 July 2023; M. Huben and J. McClarin leg.; trap, yellow pan; ECFN 11674; QCAZ.

Paratypes ECUADOR • 2 ♀♀; Sucumbíos Province; Limoncocha; 0°23′10″ S, 76°36′41″ W; 264 m a.s.l., 21 July 2024; E. Tapia, A. Tapia and N. Dupérré leg.; night collecting along trail; ECFN 11664; ZMH-A0030714; ZMH • 1 ♀; Napo Province; Parroqui Ahuano, Ahuano, Via Misahualli-Ahuano, sector Jatun Sacha, poblado Ñucanchi Causai; 1°03′52″ S, 77°36′42″ W; 387 m a.s.l.; 27 Dec. 2022; E. Tapia and I. Tapia leg.; in burrow at the base of a tree, burrow with lid, at the end of dry season; ECFN 9369; QCAZ • 1 ♀; same data as for preceding; ECFN 9370; DTC .

Description

Male (holotype)

MEASUREMENTS. Total length: 12.01; carapace length: 6.16; carapace width: 4.82; abdomen length: 5.85.

CEPHALOTHORAX. Carapace elongated-oval, dark orange-brown slightly darker along radiating lines and margin; pars cephalica flat, pars thoracica sloping; fovea slightly recurved (Fig. 16A).

CHELICERAE. Dark reddish-brown, rastellum absent; with 12 promaginal teeth, 15 intermarginal denticles; intercheliceral tumescence inconspicuous. Labium orange margin V-shaped with four cuspules (Fig. 16B). Maxillae orange, anterior lobe small; with 17 cuspules (Fig. 16B); serrula present. Sternum longer than wide (2.21 length, 2.13 width); with three rounded to oval, marginal sigilla (Fig. 16B). Eight eyes in two rows; AME 0.26, ALE 0.30, PME 0.1, PLE 0.19, PME–PME 0.56; ocular quadrangle rectangular (1.03 anterior, 1.01 posterior, 0.51 high).

LEGS. Uniformly dark orange-brown (Fig. 15A); scopula on tarsi I–II completely divided, metatarsi I–II 25% apical; tarsi III completely divided, metatarsi III absent, tarsi IV absent (just a few setae), metatarsi IV absent; tibia I with clasping spur (Fig. 16C); filiform trichobothria on all tarsi; tarsi with STC with 5–8 teeth, ITC present on all legs; tarsal organ highly elevated (observed under light microscope). Leg measurements: I 20.18 (5.39/2.88/5.07/3.72/3.12); II 18.28 (4.68/1.90/4.48/4.47/2.75); III 17.20 (4.49/2.14/3.56/4.50/2.51); IV 24.96 (6.22/2.36/5.89/7.50/2.99); leg formula 4123. Leg spination (spines on all segments except tarsi): I fe d1-2-1-1-2, pa p1, v2(apical), ti p1-1, r1-1-1, v2-2-2(apical + 1 clasping spur), mt v1-1-2(apical), p1; II fe d1-2-1-1-2, pa p2, v2(apical), ti r1-1, p1-1, v2-2-3, mt p1-1, v2-2- 2(apical); III fe d2-3-2, pa p1, r1-1, v1, ti d2-1-1, p1-1, r1-1, v2-2-3(apical); IV fe d1-1-2-3, pa p1, r1, v1, ti d1-1-1, r1-1-1, p1-1, v2-2-3(apical), mt d1-1-1, p1-1, r1-1, v2-1-2-3(apical).

ABDOMEN. Oval, dorsally dark grayish-brown with yellowish markings, with thick setae anteriorly on sclerotized socket (Fig. 15A); ventrally light yellow with dark gray meshy pattern basally; spinnerets short (PMS 0.48\PLS 1.05).

GENITALIA. Palpal tibia (2.57 length, 1.13 width); cymbium without spines (Fig. 17A–B); bulb with acutely pointed tegular heel (Fig. 17C), strongly constricted; base of embolus with two major keels, embolus twisted with wide tip (Fig. 17C–E).

Female (paratype ECFN 9369)

MEASUREMENTS. Total length: 13.31; carapace length: 6.58; carapace width: 5.65; abdomen length: 6.73. Live coloration. Carapace dark blackish-brown with reddish-brown marks on pars thoracica, chelicerae black, abdomen dark brown-orange covered with black setae; leg blackish-brown, tarsi dark brown-orange (Fig. 18A).

CEPHALOTHORAX. Carapace as in male, except fovea straight (Fig. 20A). Labium dark orange-brown, margin V-shaped; with seven cuspules (Fig. 20B). Maxillae orange, with small anterior lobe; with 18 cuspules (Fig. 20B); serrula present. Sternum wider than long (2.68 length, 3.02 width); with three marginal, oval sigilla (Fig. 20B). Eight eyes in two rows: AME 0.22, ALE 0.35, PME 0.12, PLE 0.35, PME–PME 0.66; ocular quadrangle rectangular (1.25 anterior, 1.25 posterior, 0.66 high).

CHELICERAE. As in male; rastellum absent; with 12 promarginal teeth and 20 intermarginal denticles.

LEGS. Uniformly dark orange-brown; scopula absent; filiform trichobothria on all tarsi; tarsi with STC with 3–5 teeth per row, ITC on all legs; tarsal organ highly elevated (Fig. 29E). Leg measurements: I 16.02 (4.47/2.66/3.89/3.22/1.78); II 15.84 (4.39/2.64/3.72/3.30/1.79); III 15.21 (3.88/2.26/3.08/3.83/2.16); IV 21.84 (5.39/2.39/5.33/5.87/2.86); 4123. Leg spination (spines on all segments except tarsi): I fe d1-1-1, pa 0, tib v2-2-3(apical), mt v2-2-2(apical); II fe d1-1-1, pa 0, tib v2-2-3(apical), mt v2-2-2(apical), p1; III fe d1-1, pa p1-1, ti d1-1, p1-1, r1-1, v2-2-3(apical); IV fe d1-1-1, pa r1, ti p1-1, r1-1, v2-2-3(apical), mt d1-1-1, p1-1-1-1, r1-1-1, v2-1-2-3(apical).

ABDOMEN. Oval, dark grayish-brown with yellowish markings, with thick setae on sclerotized sockets anteriorly (Fig. 19A); spinnerets short (PMS 0.67\ PLS 1.29).

GENITALIA. Internal genitalia, spermathecal bases wide, with large mushroom-shaped spermathecal heads on long stalks, separated by 2 × their diameter (Fig. 20C–E).

Natural history

The male was collected in a pitfall trap, while females were hand collected in their burrow with lid (Fig. 18B). The species was found between 231–387 m a.s.l. in the lowland evergreen forest of the Amazonian region (BsTa02) (Guevara et al. 2013b).

Distribution

Sucumbíos and Napo provinces.

Remarks

Male and females were not collected together, the match is made on habitat compatibility and morphological similarity.