Eulibitia chacuamarei, Pinzón & Damron & Pinto-Da-Rocha, 2021

Pinzón, Conchita, Damron, Brittany & Pinto-Da-Rocha, Ricardo, 2021, Three new species of Cosmetidae C. L. Koch, 1839 from South America (Opiliones Cosmetidae), Zootaxa 4984 (1), pp. 203-217 : 205-208

Eulibitia chacuamarei spec. nov.

Figs 1–2

Type material. COLOMBIA: Casanare: Holotype male (ICN-Ao-1971; penis in SEM, dissected by B. Damron, May 2018), Trinidad, Reserva La Palmita , 5°24’57.80”N, 71°35’55.80”W, 141 m elevation, J. Cabra, V. Motato & C. Alons leg. 15.– 16.8.2015 . Paratype: 1 male (MZSP-76422), with same data as for holotype .

Etymology. Dedicated to Cacique Chacuamare, who guided a group of indigenous Chiriocas founding the Trinidad municipality in Casanare, Colombia; name in the genitive case.

Diagnosis. Dorsal scutum with areas I, III and posterior margin with a pair of paramedian blunt tubercles, those of posterior margin being larger. Lateral margin with outstanding tubercles mainly on mid bulge. Color pattern as in Fig. 1A , not a typical ladder/mask. Femur IV with larger retro-distal tubercles.

Comparisons: Eulibitia chacuamarei spec. nov. can be differentiated from other species of Eulibitia by presenting a color pattern different to the ladder mask (or any dissociated form of the ladder mask). With regard to other characters E. chacuamarei spec. nov. can be distinguished from E. maculata , E. ectroxanta , E. clymnestra and E. pollux by the presence of a pair of blunt tubercles on area I (unarmed in the species previously mentioned), and from E. scalaris , E. hinscriptum , E. castor , E. helena and E. leda by the presence of prominent tubercles on retro-distal portion of femur IV.

Description. Male (holotype). Measurements: CL: 1.4; CW: 2.2; DSL: 3.8; DSW: 3.4; Fe: 2.7, 5.9,?, 5.4; Pa: 0.8, 1.1,?, 1.3; Ti: 1.7, 4.5,?, 3.4; Mt: 2.8, 5.2,?, 5.5.

Color in ethanol: Body, legs, pedipalps and chelicerae strong reddish brown (40), drawing on dorsal scutum pale yellow (89), body borders deep reddish brown (41).

Dorsum ( Fig. 1A ): Outline of dorsal scutum β-shaped, anterior margin with three projections, two rounded lateral and the medial one just subtly marked. Ocularium with well-marked medial depression and with tubercles near to eyes. Lateral margins with a rounded projection, slightly dorsal and laterally projected covering the ozopore, placed in front of coxa II. Mid-bulge with marginal small granules. Groove I slightly marked, grooves II-IV of dorsal scutum not well defined, groove IV strongly procurved. Areas I, III and posterior margin armed with a pair of medial blunt tubercles, increasing in size posteriorly, the tallest being the pair on posterior margin. Posterior margin and free tergites with a row of small tubercles.

Venter ( Fig. 1B ): Densely granulated. Coxa I with a longitudinal row of tubercles, delimited anteriorly by a cluster of tubercles. Free sternites with a row of small granules each. Anal plate densely tuberculate.

Chelicerae: Basal segment with a marginal row of granules on ectal and basal border, and a meso-apical triangular tubercle. Monomorphic. Mobile finger of chelicerae with a medial laminar longitudinal projection with six terminal teeth of the same size which do not reach extremes basally nor distally; fixed finger with a similar laminar longitudinal projection, with nine teeth that are smaller distally.

Pedipalps ( Figs 1F–G ): Trochanter with a ventral apical tubercle; femur dorsally with a row of tubercles increasing in size toward the medial region, but without reaching the distal part; ventrally with a row of longitudinal tubercles; patella with a mesal subapical laminar projection and distally rounded. Tibia mesally with a groove, its margins are laminated, strongly projected ecto-apically.

Legs ( Figs 1D–E ): I–III granulated, I with basal tarsal segments inflated; IV densely granulated, Cx IV with groin warts and an apical dorsal projection formed by three fused tubercles. Fe with five rows of longitudinal tubercles increasing in size distally, prolateral and ventral tubercles are denticle-shaped; the left one with a row of small longitudinal tubercles and a retrolateral spiniform projection greater in size; the right one with a row of small longitudinal tubercles and distally three acute retrolateral projections larger. TF: 6(3):10(3):?:7.

Penis ( Figs 2A–D ): VP subrectangular. Dorsal apophysis not very inflated dorsally, tall, moderate width. Long and cylindrical stylus. Wattle like a laminar ventral projection, reaching the middle part of stylus. A pair of MS C1 and C2 curved and distally flattened; two pairs of MS-D; D1 longer and closer to C2, distally curved and cylindrical; D2 shorter, cylindrical and acute; D1 and D2 both attached dorso-laterally to VP. Two pairs of MS A; A1 longer than A2, aligned with pairs D and C, A1 ventral-most. A small pair of MS B tubercle-like and located ventrally on VP. Lateral fields of VP covered by ms T4 and middle field and distal border without ms.

Distribution. Only known from the type locality ( Fig. 8 ).

Systematics remarks. This species can be easily determined as Eulibitia on the basis of somatic and penial morphological characters, such as areas I, III and posterior margin armed with paramedian tubercles, femur of pedipalp with a dorsal keel formed by tubercles, chelicerae monomorphic (even though no females were reviewed, we can support it due to the males examined not presenting any kind of hypertelic chelicerae, instead they are reduced); VP subrectangular, MS A1-2, D1-2, C1-2, E1-2 and B1 and by presence of microsetae T4 only covering corner/ lateral fields. Nevertheless, Eulibitia chacuamarei spec. nov. does not present a color pattern of the typical ladder mask or any dissociated form of it. This color pattern seems very continuous within species of Eulibitia ( Medrano & Kury 2017) and has received important attention recognizing species and also in relevant taxonomic changes ( Medrano & Kury 2017, Medrano et al. 2019).

Importance of understanding variation in color pattern in establishment of homologies of species and groups of species has been greatly discussed and strongly supported with evidence in Cosmetidae (i.e., Pinto-da-Rocha & Yamaguti 2013; Medrano & Kury 2016; Kury & Garcia 2016). Consequently, the absence of ladder mask in E. chacuamarei spec. nov. provides new evidence of interspecific variation within Eulibitia , suggesting that color pattern is not a decisive character for assigning a given species to this genus.

Figures

FIGURES 1A–G. Eulibitia chacuamarei spec. nov., holotype male (MZSP 3897).A–C Habitus (A dorsal, B ventral, C lateral). D–E Leg IV, trochanter, femur and patella (D dorsal, E ventral). F–G Left pedipalp (F mesal, G ectal). Scales: 1 mm.

FIGURES 2A–D. Eulibitia chacuamarei spec. nov., holotype male (MZSP 3897), penis (A dorsal, B ventral, C–D lateral). Scales: 0,05 mm.

FIGURE 8. Records of Taito and Eulibitia species described in the present paper. Inset: location of the sector represented. Lines on map represents WWF ecoregions.