Ricinoides kakum, Botero-Trujillo & Sain & Prendini, 2021

Botero-Trujillo, Ricardo, Sain, Colby E. & Prendini, Lorenzo, 2021, Systematics Of The “ Giant ” Ricinulei (Ricinoididae: Ricinoides) Of West Africa, With Descriptions Of Five New Species And Comparative Morphology Of The Male Copulatory Apparatus, Bulletin of the American Museum of Natural History 2021 (448), pp. 1-69: 51-54

publication ID

http://doi.org/ 10.1206/0003-0090.448.1.1

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scientific name

Ricinoides kakum

sp. nov.

Ricinoides kakum   , sp. nov.

Figures 4B, F View FIGURE 4 , 5 View FIGURE 5 , 6F View FIGURE 6 , 7D View FIGURE 7 , 9F View FIGURE 9 , 11F View FIGURE 11 , 12D View FIGURE 12 , 14F View FIGURE 14 , 15D View FIGURE 15 , 17F View FIGURE 17 , 18D View FIGURE 18 , 20F View FIGURE 20 , 21F View FIGURE 21 , 24B, D, F, H View FIGURE 24 , 30B, D, F, H, J View FIGURE 30 ,

33F View FIGURE 33 , 34D, tables 1, 2, 4

TYPE MATERIAL: Holotype ♂, 2 ♀ paratypes ( MRAC 217.183 View Materials ), GHANA: Central Region: Kakum Forest [Kakum National Park, 05°21′N 01°23′W], 8.xi.2005, L. Baert, R. Jocqué, and D. de Bakker, primary forest, pitfall. A microvial contains the following detached pieces of the holotype: sinistral leg III distal region with copulatory apparatus, and dextral copulatory apparatus. GoogleMaps  

DIAGNOSIS: Ricinoides kakum   most closely resembles R. atewa   , with which it shares several characters of the male, including a group of slightly elevated granules anteromedially on the ventral part of the cucullus (fig. 10B) and moderately enlarged tubercles in the distal half of the ventral surface of the pedipalp tibia (fig. 20F). The fixed process of the male copulatory apparatus of R. kakum   resembles that of R. atewa   in the laterally expanded PL lobe (figs. 30D, H), a character also shared by R. eburneus   , and the distinct subdistal serrations on the retrolateral margin of the α lobe (figs. 30D, H, J), which is unique to R. kakum   and R. atewa   (table 2). The lateral sclerites of tergite X are obsolete and the tergal membranes broad in R. kakum   (figs. 14F, 15D), whereas the lateral sclerites of tergite X are well developed and the tergal membranes narrow, in R. atewa   . Additionally, the moderately enlarged tubercles in the distal half of the ventral surface of the pedipalp tibia comprise a single retroventral row in the male of R. kakum   , unlike the male of R. atewa   , in which the tubercles comprise two (proventral and retroventral) rows.

ETYMOLOGY: The specific epithet is a noun in apposition taken from the type locality, Kakum National Park, Ghana.

DESCRIPTION OF MALE: Based on the holotype (MRAC 217.183).

Measurements: Total length 8.11 mm (table 4).

Coloration: Soma and appendages predominantly dark reddish brown, almost black. Carapace dorsolateral translucent areas yellowish. Opisthosomal tergal and pleural membranes yellow, hyaline. Cheliceral manus yellow; fingers, finger dentition, and manus toothlike process dark.

Setation: Surfaces densely covered with short, translucent, bristlelike setae, slightly expanded but not navicular, length similar to height of surrounding tuberose granules (figs. 6F, 14F). Polygonal setae absent.

Tegument surface macrosculpture: Tegument very irregular, without cuticular pits. Carapace, cucullus, opisthosomal sclerites, legs, and, to lesser extent, coxal region covered with coarse, rounded tuberose granules, evenly spaced apart, not clustered together (figs. 6F, 9F, 11F, 14F, 21F, 24B, D, F, H). Opisthosoma, pleural membranes finely and densely granular; tergal membranes more sparsely granular. Pedipalp femur dorsal, prolateral, and retrolateral surfaces finely granular; tibia with elevated oval tubercles distally (fig. 20F), some moderately enlarged and arranged into retroventral row.

Carapace: Carapace wider than long, broadest between coxae of legs II and III; trapezoidal, lateral margins curved, narrowing anteriorly (fig. 6F); anterior margin linear in dorsal aspect; posterior margin slightly procurved; median longitudinal sulcus, paired posterior marginal trans- verse sulci, and paired anterolateral longitudinal sulci distinct; paired lateral depressions aligned with coxae of legs II; posteromedian moundlike excrescence absent; dorsolateral translucent areas entirely smooth, medium sized, aligned with intersection between coxae of legs I and II, visible in dorsolateral aspect.

Cucullus: Cucullus   broadened laterally, wider than long; ventrolateral margins rounded (fig. 9F); ventral margin predominantly linear in anterior aspect, shallowly bilobate in ventral aspect, posterior surface, median row of denticulations worn; anterior surface shallowly convex, without ventral compressed surface; pair of moderately developed sublateral longitudinal sulci; ventral part with anteromedian group of slightly elevated granules, without anteromedian knoblike tubercle or elevation.

Chelicerae: Manus dorsal surface with large toothlike process distally. Movable finger longer than fixed finger, tooth row comprising six small teeth (markedly worn); sharp prodorsal longitudinal carina parallel to tooth row (opposite fixed finger); mucron with shallow but distinct prolateral excavation (opposite fixed finger) delimited by two parallel longitudinal carinae. Fixed finger tooth row comprising three or four small teeth.

Coxosternal region: Tritosternum very small, barely visible, not abutting coxae of legs I (fig. 11F); coxae of legs II–IV abutting one another medially along entire length; coxae of legs II, anterior and posterior margins almost parallel, slightly narrowing medially, not perpendicular to median axis, inclined anteriorly; coxae of legs II, posterior margin U-shaped medially; suture between coxae of legs II approximately 2× length of suture between coxae of legs III and 1.5× length of suture between coxae of legs IV.

Opisthosoma: Opisthosoma oval, longer than wide, broadest at tergite XII. Posterodorsal and posteroventral margins without spiniform granules (figs. 14F, 17F). Tergites XI–XIII each comprising median and lateral sclerites; tergite X with median sclerite, lateral sclerites obsolete, reduced to tiny sclerotized spots; median sclerites of tergites XI–XIII each with paired, shallow submedian depressions near anterior margins; lateral margins of median sclerites converging posteriorly on tergite XI and, to lesser extent, XII, slightly converging anteriorly on XIII; median sclerites of tergites XI–XIII wider than long, rectangular; margins of lateral sclerites adjacent to tergal longitudinal membranes rounded, tergal membranes broad. Sternites XI– XIII each with pair of shallow submedian depressions similar to tergites (fig. 17F). Pygidium, basal segment parallel to longitudinal axis of opisthosoma; opening very narrow, compressed laterally, width approximately one third lateral width of segment at its base (fig. 4F); posterior border narrow; dorsal surface with V-shaped notch; ventral surface entire.

Pedipalps: Femur globose, length approximately 2× depth. Tibia longer than femur; almost entirely linear (fig. 20F); robust along entire length, margins parallel in dorsal and lateral aspects; apical longitudinal carinae absent. Movable finger approximately 2× length of fixed finger.

Legs: Leg II longest, femur markedly incrassate (figs. 24B, D). Femora width (at midline) increasing in order leg IV <III <I << II; dorsal surface with longitudinal sulcus most distinct on leg IV. Leg I tibia without ventral apophyses; metatarsus subcircular in cross-section, with deep proventral depression in proximal half and without prominent ventral excrescence (figs. 4B, 21F). Leg II tibia with large ventromedian apophysis proximally (fig. 24F), not markedly hook shaped, with pointed apex, entirely covered with tuberose granules; tibia and metatarsus without pad of long translucent setae ventrally; metatarsus with shallow subproximal depression but without ventrosubmedian concavity or excrescence (fig. 24H); first to third tarsomeres short, subequal, fourth approximately 2× length of preceding tarsomeres; all tarsomeres movable. Leg III metatarsus not swollen, with moderate concavity dorsodistally; proventral surface without apical brushlike row of setae; prodorsal proximal sulcus present; metatarsus, metatarsal process, and tarsus precisely fitting together to completely encase copulatory appara- tus when tarsus retracted; metatarsal process situated basally near tibia, robust, tapering and slightly laterally compressed, longitudinal axis sinuous, apex pointing retrolaterally; lamina cyathiformis of second tarsomere slightly deeper than long, with pointed apex; subdistal (third) tarsomere with acute dorsodistal process. Leg IV tarsus not swollen. Legs III and IV terminal tarsomere apex, dorsal margin sublinear, covering ungues. Leg I tarsus and legs II–IV terminal tarsomeres without ventrodistal papillae.

Copulatory apparatus: Fixed process, PL lobe greatly expanded and dorsoventrally compressed (figs. 30D, H). Distal lobular region, primary α lobe very long, narrow, dorsoventrally compressed distally and, to lesser extent, proximally (figs. 30B, D, F, H, J, 33F); origin submedial, curving toward ventral surface; prolateral margin smooth, retrolateral margin with distinct subdistal serrations. Primary β lobe medium sized, distinctly bicuspid, with β 1 and β 2 pointed. rsd lobe medium sized, pronounced, associated with distinct subdistal emargination. Secondary pd and rd lobes well developed, pointed. Movable process slender, slightly flexible, narrowing distally; apex simple, entire.

SUPPLEMENTARY DESCRIPTION OF FEMALE: Based on paratypes (MRAC 217.183). Resembles male except as noted.

Measurements: Total length 8.00 mm (table 4).

Tegument surface macrosculpture: Pedipalp tibia with oval tubercles on ventral surface smaller than in male.

Carapace: Posteromedian moundlike excrescence absent (fig. 7D).

Cucullus: Ventral   part without group of elevated granules anteromedially; ventrolateral margins rounded; ventral margin predominantly linear in anterior aspect.

Coxosternal region: Coxae of legs II–IV abutting one another medially along entire length (fig. 12D); coxae of legs II, posterior margin U-shaped medially.

Opisthosoma: Opisthosoma oval (figs. 15D, 18D). Tergites XI–XIII, median sclerites wider than long; XIII, lateral margins of median scler- ite converging slightly anteriorly. Opening of basal segment of pygidium very narrow, compressed laterally.

Legs: Leg I metatarsus without proximal depression proventrally. Leg II femur unmodified, longer than but similar in shape to femora of other legs; tibia without ventromedian apophysis; metatarsus without subproximal depression ventrally.

Spermathecae: Anterior wall of bursa copulatrix with pair of medium-sized, slightly pigmented, rounded areas. Anterior surface with eight hard sacculiform structures sinistrally and five dextrally, variable in size, some markedly elongate (fig. 34D). Spermathecae follicular, each comprising soft, elongate tube terminating in tapering duct, situated submedially on anterior surface of bursa copulatrix adjacent to dorsal margin. Posterior genital lip as in figure 34D.

DISTRIBUTION: This species is known only from the type locality, Kakum National Park, in the Central Region of Ghana (fig. 5).

ADDITIONAL MATERIAL EXAMINED: GHANA: Central Region: Kakum Forest [Kakum National Park, 05°21′N 01°23′W], Kuntan trail, 159 m, 14–25.xi.2005, R. Jocqué, D. de Bakker, and L. Baert, secondary forest, pitfall, 1 ♀ (MRAC 217.210).


Departamento de Geologia, Universidad de Chile