Timogenes pipanaco, Barrios-Montivero & Salas & Ojanguren-Affilastro, 2024

Barrios-Montivero, Alexis E., Salas, Liliana B. & Ojanguren-Affilastro, Andrés A., 2024, Description of Timogenes pipanaco sp. nov., (Scorpiones, Bothriuridae) a new salt flat species from north western Argentina, Zootaxa 5536 (2), pp. 277-290 : 279-288

Timogenes pipanaco n. sp. Barrios-Montivero & Ojanguren-Affilastro

( Figs. 1‒5A, B, D, F‒G ; 6 , 7 ; Tables 1, 2)

Type material. Holotype male: Argentina, Catamarca province, Pomán Department, Pipanaco salt flat, 28°19’0.96”S, 66°22’30.65”W, 751 m a.s.l., 15/X/2023, Barrios-Montivero, & De-Bonis, coll. ( MACN) ; Paratypes, 5 males, same data as holotype ( MACN) ; 1 female, Argentina, Catamarca province, Pomán Department, Pipanaco salt flat, 28°38’51.85”S, 66°22’39.22”W, 900 m a.s.l., 24/II/2023, Morales, coll. ( MACN) .

Other studied material. 1 male, same locality as holotype, 06/XI/22, Barrios-Montivero, De-Bonis, & Morales, coll. ( FACEN-UNCA) ; 1 male, same locality as holotype, 21/X/23, Barrios-Montivero & De-Bonis, coll. ( FACEN-UNCA) .

Etymology. The specific epithet pipanaco is a noun in apposition referring to the Pipanaco salt flat, a plain area of 600 km 2 raging from south central Catamarca province to north central La Rioja province in north western Argentina.

Diagnosis and comparisons. Timogenes pipanaco sp. nov. can be separated from all species of the genus because its stridulatory organ is poorly developed, and reduced to some sparse granules (being completely absent in the only studied female) ( Figs. 5A–B ), whereas in the rest of the species it is well developed, with granules forming a V shaped carina in pretergites III, IV, V, and VI ( Fig. 5C ). Additionally, the only known female of T. pipananco sp. nov. bears VM and VSM carinae in the anterior ventral third of metasomal segments I and II ( Fig. 5G ), whereas the rest of the species of the genus do not bear ventral carinae in these metasomal segments.

Timogenes pipanaco n. sp. ( Fig. 3 ) is most similar to T. haplochirus from central western Argentina, both being the only two species of the genus with the internal excavation of male chela poorly developed and barely visible ( Fig. 4D ); whereas in the rest of the species of the genus this excavation is very conspicuous and well developed, limited by a conspicuous posterior crest ( Fig. 5E ) ( Ojanguren-Affilastro 2005). Both species can be separated because T. pipanaco sp. nov. males bear glands in the dorsal surface of metasomal segment V and telson ( Fig. 6A ), whereas T. haplochirus males only bear glands in metasomal segment V ( Ojanguren-Affilastro 2005). Both species can also be separated because T. haplochirus bears 6 ventral trichobothria in pedipalp chela, whereas T. pipanaco sp. nov. bears 7 ( Fig. 4A ).

Timogenes pipanaco sp. nov. is, in general, smaller than T. haplochirus . Timogenes pipanaco sp. nov. length ranges from 27 to 43 mm ( Table 1), with most specimens under 35 mm; whereas T. haplochirus length ranges from 37 to 56 mm.

Description. Based on the holotype male (MACN), paratypes males and a single paratype female (MACN). Total length, males: 26.88–42.71 mm, (N = 6; mean = 33.3 mm), 32.05 mm in the only studied female ( Tables 1, 2).

Colour: Light yellowish, almost completely devoid of pigment. Pedipalps slightly darker. Median and lateral eyes black, aculeus dark brown. The rest unpigmented ( Figs. 3A–D ).

Chelicerae: Anterior margin of movable fingers strongly curved; movable fingers with one subdistal tooth.

Pedipalps: Femur with VI and DE carinae granular, extending the entire length of the segment in males, with one DI, one D, and two DE macrosetae ( Fig. 4G ), female with less granular carinae; tegument slightly granular. Patella, DI and VI carinae granular, extending the entire length of the segment in males, less developed in female, anterior surface slightly granular, remaining surfaces smooth ( Fig. 4F ). Chela manus ( Figs. 4A–E ) robust, more so in males, tegument granular in males, smooth in female, length/height ratio, males: 1.18–2.64 (N = 6; mean = 2.07), 2.56 in the only studied female; length/width, males: 1.66–3.83 (N = 6; mean = 2.84), 3.41 in the only studied female ( Table 2), internal surface smooth in female, males with a barely visible and extremely shallow and granular depression near articulation of movable finger ( Fig. 4E ), ventrally with a well-developed ventral median carina in males, smooth in female; fingers short, with a median row of denticles and with five pairs of accessory denticles; the basal external denticle is usually part of the median row. Trichobothrial pattern neobothriotaxic major type C, with three accessory trichobothrium in V series of chela; femur with 3 trichobothria (d, i, e), one macroseta (M1) between d and i; patella with 19 trichobothria (2 d, i, 3 et, est, 2 em, 2 esb, 5 eb, 3 V), with esb 2 petite; chela with 29 trichobothria (Dt, Db, 5 Et, Est, Esb, 3 Eb, dt, dst, dsb, db, et, est, esb, eb, ib, it, 7 V), with Et4 petite, Esb forming triangle with Eb 1 and Eb 2.

Carapace:Anterior margin convex, with two median setae. Surface: smooth.Anterior longitudinal sulcus absent, postocular furrow and lateral sulci present and well developed. Median ocular tubercle medium sized, placed in the middle of the carapace; interocular sulcus absent; median ocelli small, facing towards the lateral margins, ca. two diameters apart, with one micro seta behind each eye. Lateral ocelli pattern type 3A; with three small lateral ocelli on each side of carapace, two of them anteriorly, third ocellus half the size to the other two, about half diameter above them.

Legs: Surfaces with some scattered granules. Basitarsi each with two pedal spurs, asymmetrical in legs I and II being the internal half of the size the external ( Fig. 7D ), and symmetrical in legs III and IV ( Fig. 7E ). Telotarsi, ventrally with a ventromedian row of hyaline setae, and paired ventrosubmedian spines: 1/ 1 in telotarsus I, 2/ 2 in telotarsus II and 3/ 3 in telotarsi III and IV. Ungues barely curved and well developed, asymmetrical in legs I and II, being the internal about 30% smaller than the external; symmetrical in legs III and IV.

Pectines: Well developed. Tooth count, males: 16–18 (N = 6; median = 17) female with 13–13 teeth; internal median lamella more developed in female than in males.

Sternum: With two conspicuous subtriangular lateral lobes clearly connecting medially, with two macrosetae on each. Genital opercula: Sclerites subtriangular, fused.

Tergites: Tergites I–VI surface smooth; stridulatory organ of pretergites reduced to some scattered granules in segments III, IV, V and VI ( Fig. 5B ) in males, absent in female ( Fig. 5A ); tergite VII surface smooth, with four longitudinal granular carinae in posterior half of the segment.

Sternites: Sternites III–VI surface smooth, except for some lateral granules, with elliptical spiracles; sternite VII smooth anteriorly, posterior half with some scattered granules and two VSM carinae much more developed in the female specimen than in males ( Figs. 5F–G ).

Metasoma: Segment I dorsal surface smooth, DL carina formed by scattered granules in the posterior two thirds of the segment; lateral surface: LM and LIM granular in posterior two thirds of the segment, with one LIM seta; ventral surface with barely visible VM and VSM carinae in posterior third of the segment in males ( Fig. 5F ), female with VM and VSM granular carinae in posterior third of the segment ( Fig. 5G ); with six ventral macrosetae arranged in three rows of two macrosetae each, an anterior row of two VL setae, a median row of two VL setae, and a posterior row in the posterior margin of the segment of two VSM setae; segment II similar to segment I, but with a LM macroseta; segment III: as segment II but less granular, with one DL seta, LIM carina restricted to posterior third of the segment, ventrally smooth, the rest as segment II; segment IV: elongated, DL carina granular, extending almost the entire length of the segment; with one DL seta; LM carina granular, extending the posterior two thirds of the segment, with six setae (fig. 5E), LIM carina absent, ventrally with 10 macrosetae, an anterior pair of two VL setae, a median row of four macroseta (2 VL and 2 VSM), a posterior pair of two VL macrosetae and a distal pair of two VSM macrosetae, surfaces smooth. Segment V: elongated, length/width, males: 1.61–2.16 (N = 6; mean = 1.81), 1.43 in the only studied female ( Table 2); dorsal surface smooth, males with two conspicuous and straight DL glands in posterior two thirds of the segment ( Fig. 6A ), absent in female, LM carinae granular, extending the entire length of the segment, with 15 macrosetae ( Fig. 5D ), ventrally granular in anterior two thirds, almost completely smooth in posterior third; VL carinae granular and extending the entire length of the segment, with four VL macrosetae on each side; VM carinae formed by a line of scattered granules in the anterior half of the segment; VSM carinae forming a transversal carina in posterior third of the segment, joining laterally with VL carinae ( Figs. 6B–C ); with some scattered VSM granules in the anterior half of the segment, not fusing with the transversal carinae; medially with a pair of VSM macrosetae, with four macrosetae in posterior margin, two VL and two VSM. Telson : vesicle globose, more so in female ( Figs. 6D–E ), ventral surface granular, dorsal surface smooth, in males there is a pair of dorso-sub-median elliptical telson glands ( Fig. 6A ); aculeus medium sized, not very curved, shorter in female specimen ( Figs. 6D–E ).

Hemispermatophore: Distal lamina slender, similar in size to the basal portion, almost completely straight, squared apex, distal crest small and curved anteriorly, near the distal margin; frontal crest well developed, occupying the basal two thirds of the distal lamina ( Figs. 7A–B ); internal margin of the internal lobe elongated and protruding; posterior margin of the basal lobe folded and with some scattered basal granules, capsular cavity well developed ( Fig. 7C ).

Distribution. Timogenes pipanaco sp. nov. has only been collected in the Pipanaco salt flat, between 751 and 900 m. asl. It is placed in southwestern Catamarca province and northwestern La Rioja province, in north-western Argentina. This is a large arid depression of 600 km ² which is part of the Pipanaco basin. This area is surrounded by mountain ranges that can reach more than 4000 masl; northerly, by the El Candado, Capillitas and Belén hills; to the west, by the hills of Vinquis, Zapata and Fiambalá; towards the east, by the summits of the Chilca and Ambato hills; and to the south by the hills of Velazco (La Rioja) ( Paoli et al. 2011; Tálamo et al. 2016) ( Fig. 2 ).

Ecology. The sites where T. pipanaco sp. nov. was collected are located in an extremely arid area. The moistureladen winds from the northeast almost completely discharge their moisture content on the eastern slopes of the surrounding hills, resulting in dry and warm winds on the western side. This area corresponds phytogeographically to the Monte province ( Morlans 1995), more precisely to “Monte Septentrional” ( Arana et al. 2021) ( Fig. 1 ). It is an admixture of open areas devoid of vegetation with dunes, xerophytic scrub formed by Larrea cuneifolia Cavanilles 1800 , Larrea divaricata Cavanilles 1800 , Bulnesia retama (Gillies ex Hook. & Arn.) Griseb 1874 ( Zygophyllaceae ), Senegalia gilliesii (Steud.) Seigler & Ebinger 1947 , Parkinsonia praecox (Ruiz & Pav. ex Hook 1999) ( Fabaceae ), Ephedra sp. ( Ephedraceae ) and xerophytic forests formed by Neltuma alba C.E. Hughes & G.P. Lewis 2022 , Neltuma chilensis C.E. Hughes & G.P. Lewis 2022 and Neltuma flexuosa C.E. Hughes & G.P. Lewis 2022 , Geoffroea decorticans (Gillies ex Hook. & Arn.) Burkart 1949 and Vachellia caven (Molina) Seigler & Ebinger 1810 ( Fabaceae ).

Most specimens of T. pipanaco sp. nov. were collected during a systematic monthly sampling carried out between October 2022 and October 2023, in the Pipanaco salt flat, with pitfall traps and UV collection, within the framework of the doctoral project of the first author. This species appeared in three collection events, two in November 2022, and one in October 2023, all during the austral spring, being all specimens active males collected with UV light. The presence of active males in Bothriuridae , is usually related with the peak of activity of the species, and in some species of Timogenes this peak can be extremely brief and explosive ( Nime et al. 2014; Ojanguren-Affilastro unpublished data). All this suggests that the activity period of this species is restricted to spring. The female paratype was collected at the end of February of 2023, in the austral summer, during a seasonal sampling with pitfall traps between November 2022 and May 2023. The presence of a single active female in summer is not necessarily an evidence of an extended activity period during the whole warm season, since it is common to find sparse active females and juveniles much later than the end of the mating season ( Nime et al. 2014; Polis 1980). We have carried out additional samplings in different locations with similar environments but outside the Pipanaco salt flat, during 2022, 2023 and 2024 (Barrios-Montivero unpublished data); however, the new species herein described was not found in neither of them. All this, leads us to infer that the activity period of T. pipanaco sp. nov. takes place in spring, and that its distribution is restricted to the Pipanaco salt flat.

Timogenes pipanaco sp. nov. is sympatric with Timogenes sumatranus Simon 1880 , Timogenes elegans (Mello-Leitão 1931) , Timogenes dorbignyi (Guérin-Méneville 1843) , Brachistosternus pentheri Mello-Leitão 1931 , Vachonia sp. and Bothriurus olaen Acosta 1997 .

Figures

FIGURE 1. Dunes of the Pipanaco salt flat, in Catamarca province, Argentina, type locality of Timogenes pipanaco sp. nov.

FIGURE 2. Distribution map of Timogenes pipanaco sp. nov. (red diamonds) and Timogenes haplochirus (black circles). The Pipanaco basin is marked with a dashed line. The “Monte” biogeographical province is depicted in yellow, the “Yungas” province is depicted in green, the “Altoandina Cuyana” biogeographical province is depicted in blue, the “Puna” biogeographical province is depicted in orange, and the “Chaco” biogeographical province is depicted in brown (following Arana et al. 2017).

FIGURES 3. Timogenes pipanaco sp. nov., habitus. A. Male, dorsal aspect; B. Male, ventral aspect; C. Female, dorsal aspect; D. Female, ventral aspect. Scale bars: 1 cm.

FIGURES 4A–G. Timogenes pipanaco n sp.; A. Right pedipalp chela, male, ventral aspect; B. Right pedipalp chela, male, external aspect; C. Right pedipalp chela, male, dorsal aspect; D. Right pedipalp chela, male, internal aspect; F. Right pedipalp patella, male, external aspect; G. Right pedipalp femur, male, dorsal aspect; E. Right pedipalp chela, female, internal aspect. Scale bars: 1 mm.

FIGURES 5A–B and D, F–G. Timogenes pipanaco n sp.; A. Tergite V, female, dorsal aspect; B. Tergite V, male, dorsal aspect, D. Metasomal segment IV, male, lateral aspect; F. Sternite VII and metasomal segments I and II, male, ventral aspect; G. Sternite VII and metasomal segments I and II, female, ventral aspect. C, E. Timogenes dorbignyi. C. Tergite V, male, dorsal aspect; E. Right pedipalp chela male, internal aspect. Scale bars: 1 mm.

FIGURES 6A–E. Timogenes pipanaco sp. nov.; A. Metasomal segment V and telson, male, dorsal aspect; B. Metasomal segment V, male, ventral aspect; C. Metasomal segment V, female, ventral aspect; D. Metasomal segment IV, male, lateral aspect; E. Telson, male, lateral aspect; F. Telson, female, lateral aspect. Scale bars: 1 mm.

FIGURES 7A–E. Timogenes pipanaco sp. nov.; A. Left hemispermatophore, internal aspect; B. Left hemispermatophore, external aspect, Scale bars: 1 mm; C. Detail of lobe region; D. Telotarsus II, prolateral aspect; E. Telotarsus III, prolateral aspect. Scale bars: 0.5 mm.