Rhaucus gaiterus Pinzón-M & Pinto-Da-Rocha, 2024, sp. nov.
Creators: name: Pinzón-M, Conchita
name: Pinto-Da-Rocha, Ricardo
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Opiliones
Cosmetidae
Rhaucus
Rhaucus gaiterus

description: Rhaucus gaiterus sp. nov.
(Figs 5–7, 12)
Type material: Colombia, Bolívar: Holotype male (MUSENUV-Ar 2620, penis prepared for SEM, then preserved in a microvial with the holotype), San Jacinto, vereda Las Flechas, 9°50’59”N, 75°10’0.8”W [319 m], C. Pinzón leg. IX.2015.
Etymology: From the Spanish word “gaitero,” referring to a person who plays the Gaita, a traditional musical instrument widely used in the cultural folklore of San Jacinto, Bolívar, and Montes de María in Colombia.
Diagnosis: DS smaller than in the remaining species (more than 5 mm in R. artifex sp. nov., R. vulneratus, R. quinquelineatus, R. serripes, R. robustus, and R. serratus comb. nov.; between 4.8 and 5 mm in R. florezi and R. marmoratus comb. nov.) (see García & Kury, 2017). The scent gland opening is a small lateral projection of the DS, lacking a dorsal fold posterior to the ozopore (Figs. 5C and 11F) (dorsal fold present in the remaining species). The descending channel is present and visible in dorsal view (Fig. 11F) (covered by the dorsal fold in the remaining species). The color pattern of DS features an almost complete arborescent chevron, a complex omega stripe, and abdominal grooves with patches (see Figs. 5A and 6A). Lateral projections of DS are sub-rectangular and laterally directed (Fig. 6A) (sub-triangular and blunt in the remaining species). Pedipalpal Fe is sub-circular, weakly armed on the dorsal and ventral margins (Fig. 6G) (not circular and with a row of conspicuous tubercles on each margin in the remaining species). Leg IV has Fe not strongly armed; some tubercles are restricted to the distal portion in ventral view (Fig. 6D–F) (strongly granulated ventrally in the remaining species).
Description: Male. Measurements: CL: 1.7; CW: 3.0; DSL: 4.6; DSW: 4.1; Fe: 2.2, 4.8, 3.6, 5.0; Pa: 0.7, 1.0, 1.0, 1.0; Ti: 1.5, 3.9, 1.9, 2.7; Mt: 2.8, 4.8, 3.5, 5.3.
Color in ethanol: DS Vivid yellow (82); legs and chelicerae Vivid greenish yellow (97); pedipalps Brilliant greenish yellow (98). Color pattern on dorsal scutum Pale yellow green (121), forming an incomplete arborescent chevron, incomplete backbone, and a complex omega stripe.
Dorsum: (Fig. 5A and 6A) DS with constrictions I and II well marked, mid-bulge well developed laterally, and long coda. Anterior projections of DS are sub-rectangular and laterally directed. Scent gland opening without marked ID, without DF, and with clearly distinguished DC. Wide and low ocularium with small tubercles near the eyes. Slightly granulated tegument. Posterior margin and FT with a row of moderate-size tubercles. Area I with a pair of paramedian conical-shaped tubercles; area III with a pair of long spiniform tubercles. All sulci of scutum and midline well marked.
Venter: Granulated gnathocoxae. Cx I with a longitudinal anterior row of tubercles.
Chelicerae: (Fig. 6B) Hyperthelic. Apical margin of the basal segment with digitiform projections, longer towards the mesal margin. Ectal margin with digitiform projections. Mobile finger with medial concavity. Fixed finger without teeth.
Pedipalps: (Fig. 6G–H) Fe with a curved ventral margin, a longitudinal row of small tubercles close to each other, and a ventral-apical tubercle; dorsal margin with an anterior longitudinal keel and some spaced tubercles. Pa with ectal and mesal margins longitudinally projected. Mesally with a dorso-apical tubercle. Ti elongated, distally with an ectal projection not well marked, mesally with a longitudinal ditch. Ta subtriangular, laterally extended with short setae on margins. Short claw, not exceeding mid-size of Ta.
Legs: (Fig. 6C–F) Cx I and II with prominent anterior and posterior projections; both projections on Cx II bear a dorsal tubercle, with the anterior one located near the ozopore on DS. Cx IV has groin warts formed by a group of three tubercles, with a dorsal apical apophysis that has a dorsal-most blunt tubercle (Fig. 5D). Tr I has a retrolateral basal tubercle; Tr III has two retrolateral tubercles, one basal and one distal; Tr IV has a basal retrolateral tubercle. Fe I, III, and IV are curved, while Fe II is straight; all Fe are granulated. Fe III has two ventral distal rows of tubercles extending from the medial to the distal portion; Fe IV has two ventral rows of distal tubercles, larger towards the apex. Pa and Ti are tuberculate. Mt I–IV have pale rings. FT: 6(3):?-12:?-7:?-7.
Penis: (Fig. 7A–D) VP sub-rectangular, narrower at the base than distally, with a concave distal margin. Two pairs of MS C; two pairs of MS D, with D1 being long, acute, and cylindrical, located closer to the MS C pairs; D2 is shorter, dorsally attached, and closer to a unique pair of MS A, which share a similar appearance with MS D1. MS E is absent (see discussion), and a pair of MS B is located at the distal portion of the truncus, formed by a structure resembling an expansive orifice like a large pore with smooth margins, areolate. VP with lateral fields covered by microsetae T4, and the middle portion covered by microsetae T2. Wattle extended ventrally, with stylar barbs on the apical portion and an extended slit. Dorsal process is laterally flattened and bent ventrally, forming a spoon-shaped structure.
Female: Unknown.
description: Published as part of Pinzón-M, Conchita & Pinto-Da-Rocha, Ricardo, 2024, Two new species of Rhaucus Simon, 1879 reveal putative synapomorphies related to the microstructural morphology of male genitalia (Opiliones: Cosmetidae), pp. 35-56 in Zootaxa 5555 (1) on pages 43-46, DOI: 10.11646/zootaxa.5555.1.3, http://zenodo.org/record/14508494