Ibotyporanga kanoe Huber sp. nov.

urn:lsid:zoobank.org:act: 90329555-8348-48B3-8DA3-0897611BE788

Figs 22B, 60B, 65–68

Ibotyporanga Br16-149 – Eberle et al. 2018: suppl. file, p. 52 (molecular data). — Huber et al. 2018: 55.

Diagnosis

Males are easily distinguished from most known congeners (except I. naideae and I. diroa) by long and slender procursus without dorsal branch (Fig. 66A–C); from I. naideae by shorter cheliceral apophysis not directed upwards (Fig. 67A–B) and by details of genital bulb (without strongly developed retrolateral tubercles; tip of embolus without small pointed dorsal apophysis; Fig. 66F); from I. diroa also distinguished by presence of prolateral process proximally on procursus (arrow in Fig. 66B) and by very short and indistinct (basically absent) prolateral sclerite on bulbous part of genital bulb (Fig. 66D). Females are externally similar to several congeners with relatively long epigynum (similar to I. naideae but relatively shorter) and weakly curved anterior pocket (Fig. 68A–B), but differ by pair of short but distinct tubes in internal genitalia (Figs 67C, 68F–G) (much longer in I. naideae).

Etymology

The species name honors the Kanoê, an indigenous people of Brazil that lives in the State of Rondônia; noun in apposition.

Type material

Holotype

BRAZIL – Rondônia • ♂; Floresta Nacional do Jamari, Pedra Grande; 9.198° S, 63.081° W; 160 m a.s.l.; 25 Oct. 2016; L.S. Carvalho and B.A. Huber leg.; CHNUFPI 3796.

Paratypes

BRAZIL – Rondônia • 1 ♂; same collection data as for holotype; CHNUFPI 3752 • 1 ♀, 4 juvs; same collection data as for holotype; CHNUFPI 3489 • 3 ♀♀; same collection data as for holotype; CHNUFPI 3702, 3731, 3792 • 2 ♂♂, 1 ♀; same collection data as for holotype; CHNUFPI 5898 [deposited in ZFMK Ar 24358] .

Other material examined

BRAZIL – Rondônia • 1 ♂, 1 ♀, in pure ethanol; same collection data as for holotype; CHNUFPI 5899 [deposited in ZFMK Br16-303; female prosoma and legs used for molecular work] .

Description

Male (holotype)

MEASUREMENTS. Total body length 2.3, carapace width 0.97. Distance PME–PME 75 µm; diameter PME 85 µm; distance PME–ALE 30 µm; distance AME–AME 20 µm; diameter AME 55 µm. Leg 1: 6.27 (1.67+0.35 +1.62 +2.03 + 0.60), tibia 2: 1.38, tibia 3: 1.23, tibia 4: 1.73; tibia 1 L/d: 14; diameters of leg femora 0.21–0.22, of leg tibiae 0.12.

COLOUR (in ethanol). Prosoma and legs mostly light ochre, carapace medially slightly darker brown, including ocular area and clypeus; legs with very indistinct darker rings on femora (subdistally) and tibiae (proximally and subdistally); abdomen gray with many darker internal marks dorsally and laterally; ventrally with distinct light brown plates in front of gonopore and in front of spinnerets.

BODY. Habitus similar to I. naideae (cf. Fig. 55C). Ocular area slightly raised. Carapace with distinct but shallow thoracic groove. Clypeus with sclerotized rim with median notch. Sternum wider than long (0.68/0.52), with pair of distinct anterior processes near coxae 1. Abdomen globular.

CHELICERAE. As in Fig. 67A–B; width 0.39; with strong median frontal apophysis; stridulatory files fine but clearly visible in dissecting microscope.

PALPS. As in Fig. 65; coxa unmodified; trochanter with distinct ventral protrusion; femur proximally with distinct retrolateral process not directed toward distal, with prolateral stridulatory pick, distally widened but unmodified; femur-patella joints and tibia-tarsus joints not shifted toward one side; tibia with distinct ventral process; tarsus without dorsal process; procursus (Fig. 66A–C) proximally wide and with prolateral process, curved towards ventral, distally very long and slender, curved towards dorsal, with narrow but distinct light prolateral band; genital bulb (Fig. 66D–F) with very short and indistinct (practically absent) prolateral sclerite on bulbous part, embolus with distal sclerite directed towards retrolateral.

LEGS. Without spines but with longer hairs ventrally on femora; without curved hairs; with several rows of short vertical hairs on tibiae 1 and 2; retrolateral trichobothrium of tibia 1 at 59%; prolateral trichobothrium absent on tibia 1; tarsus 1 with ~5 pseudosegments, distally fairly distinct.

Variation (male)

Tibia 1 in five males (incl. holotype): 1.60–1.90 (mean 1.76). Largest males also with larger chelicerae and palps, but shapes of genital structures apparently identical. Measurements of largest male: carapace width 1.23; tibia 1 length 1.90; palpal tibia length/diameter: 0.50/0.30 (versus 0.40/ 0.25 in holotype).

Female

In general, similar to male but clypeus unmodified, tibia 1 with few short vertical hairs. Tibia 1 length in five females: 1.83–2.17 (mean 2.02). Epigynum (Fig. 68A–B) anterior plate trapezoidal, posterior margin slightly and evenly indented, anteriorly with wide and shallow pocket; posterior plate large but simple, rectangular. Internal genitalia (Figs 67C, 68C–G) with heavily sclerotized median structure, with pair of relatively large, weakly sclerotized pore plates, and pair of short ducts originating laterally from membranous anterior structure and leading into widened terminal sacs.

Distribution

Known from type locality only, in Brazil, Rondônia (Fig. 60B).

Natural history

The type locality is located within the Floresta Nacional do Jamari, a sustainable use conservation unit, with about 223 000 hectares of dense Amazon rainforest. About 43% of its area is used for log extraction and cassiterite mining activities (https://www.gov.br/agricultura/pt-br/assuntos/servico-florestal-brasileiro/ concessao-florestal/concessoes-florestais-em-andamento-1/floresta-nacional-do-jamari-ro). The sampling in this conservation unit was performed at six sites (Fig. S8A), but Ibotyporanga was only found on a granite rock outcrop, which is dominated by exposed rock and scattered low vegetation adapted to drier conditions (Figs 22B and S 9A–B). In the surrounding forest, we found several genera of Pholcidae usually encountered in humid Brazilian forests ( Metagonia, Mesabolivar, Litoporus), but no Ninetinae . On the outcrop, Ibotyporanga was found by turning rocks. Upon turning the rocks, the spiders ran rapidly, making them difficult to catch.

The conservation status of this species should be formally assessed. From satellite images (Fig. S8), we estimate its extent of occurrence (EOO) to be about 0.13 km ², i.e., the rock outcrop area. The sampling site is less than 100 meters from a mining site (Taboquinha) inside the conservation unit (Fig. S9B). The mining activities are active and currently under expansion, getting closer to the rock outcrop (Fig. S9). This dynamic potentially decreases habitat quality, threatening Ibotyporanga kanoe sp. nov. to extinction.