﻿Review of the genus Karschia Walter, 1889 from Xizang, China (Solifugae, Karschiidae)

﻿Abstract The species of the genus Karschia Walter, 1889, collected from Xizang, China, were reviewed. A total of six species were recognized using morphological and molecular data, Karschia (Karschia) tibetana Hirst, 1907 is redescribed based on newly collected males and females, and five new species, Karschia (Karschia) dingyesp. nov., Karschia (Karschia) lhasasp. nov., Karschia (Karschia) zhuisp. nov., Karschia (Karschia) shigatsesp. nov., and Karschia (Karschia) namlingsp. nov., are described.

The genus Karschia sets itself apart from other genera within Karschiidae easily by possessing a rotatable, long, and rolled flagellum, often described as sessile (Birula 1922(Birula , 1938;;Bird et al. 2015).This flagellum maintains a core resemblance to a plumose seta, typically adorned with a delicate fringe of setae, which Lawrence (1954) mistakenly referred to as "cilia".The flagellum of Karschia is understood to comprise three components: a distinct stalk, a basal peg sharing similarities with the base of a whip-like flagellum, and an elongated filiform structure resembling a shaft, thus resembling a composite flagellum (Bird et al. 2015).Roewer (1934) described the flagellum of Karschia as an elongated double-walled tubular structure, originating from a seta that widened along its length.The margins of the flagellum rolled inward until they nearly formed a closed canal, suggesting a process of longitudinal in-furling.However, it is possible that the hypothesized double membrane was lost.Consequently, the flagellum of Karschia resembles a composite flagellum, with identifiable components such as a "stalk", "base", and "shaft", though its sessile nature awaits further investigation (Bird et al. 2015).
The flagellar complex of Karschia comprises several structures: a long, typically coiled, filiform flagellum; plumose setae, located ventrally to the flagellum and modified to varying degrees, including broadening referred to as flagellar complex plumose (fcp) setae; and one or two acuminate subspiniform setae, usually swollen at the base and situated dorsoproximal to the flagellar attachment point, labeled as flagellar complex subspiniform (fcs) setae (Gromov 2004;Bird et al. 2015).
Males of Karschia lack spiniform setae on the anterior edge of the propeltidium (on both sides of the ocular tubercle) (Gromov 1998(Gromov , 2004)).Females of this genus exhibit differences, notably in the morphology of the more modified genital segment.The subgenus Karschia differs from the subgenus Rhinokarschia by the absence of a hornlike process on the fixed finger of the chelicerae in males (though a low crest may be present instead), and by the presence of transverse, oval, or triangular-shaped genital sternites in females, which cover the genital opening (Gromov 2004).
The systematics and phylogenetic relationships of Karschia remain poorly understood, as its congeners are relatively local and rare species (Gromov 2004).Species diagnoses in this genus are mainly based on male characters.Female descriptions are limited to body size and coloration, chelicerae dentition, and the shape and number of ctenidia on the fourth abdominal segment.The female genital segment has previously been considered of little or no taxonomic significance in species diagnosis (Roewer 1933;Birula 1938).This makes it difficult to identify female specimens.In order to address the issues related to female identification, Gromov (2004) proposed that for female diagnosis, the shape and size of the ctenidia on the fourth abdominal segment, as well as the shape, size, and relative arrangement of the sclerites of the genital segment are more reliable than others, i.e., the chelicerae dentition, the number of ctenidia on the fourth abdominal segment, the body size and coloration.
Xizang Autonomous Region, located in the southwestern part of the Qinghai-Xizang Plateau and known as the "Roof of the World," has an average elevation exceeding 4,000 meters.The high altitude and unique geographical location form its distinctive climate and rich biodiversity, including many rare and endangered species.Xizang has become a hotspot and crucial area for global biodiversity research in recent years.However, research on Solifugae in Xizang has been limited, with only four species previously reported: Galeodes caspius Birula, 1890, Karschia tibetana Hirst, 1907, Karschia nubigena Lawrence 1954, and Triditarsus tibetanus Roewer, 1933.During our biodiversity survey, we revealed a widespread distribution of Solifugae in Xizang.During the process of identifying collected specimens, we observed a high level of diversity within the genus Karschia in Xizang through comparison with diagnoses, descriptions, and drawings in original literature of all known species.This research used morphological characters and molecular data to investigate the taxonomy of Solifugae in Xizang.To solve the problem of male and female combinations and to ensure the precision of our morphological identifications, we carried out genetic distance comparisons on suspected new species.For each species, both a male and a female specimen were chosen to extract genomic DNA and the COI gene was amplified.In conclusion, comparisons of morphological characteristics and molecular genetic distances have led us to conclude that there are seven species of Karschia distributed in Xizang.

Materials and methods
The specimens were collected during the day by hand from under stones, and preserved in 75% and 95% alcohol, respectively.Photographs were taken using a Leica M205A stereomicroscope equipped with a DFC 550 CCD and an Olympus BX51 microscope equipped with a Kuy Nice CCD camera and were imported into Helicon Focus v. 7 for stacking.Plates and photographs were edited and retouched using Adobe Photoshop 2022.Drawings was made using the Inkscape software (v.1.0.2.0).All measurements are in mm.Pedipalp measurements are shown as: total length (femur, tibia, metatarsus, tarsus); leg measurements are shown as: total length (femur, tibia, metatarsus, tarsus, claw).All specimens are deposited in the Museum of Hebei University (MHBU), Baoding, China.
Descriptions follow the format of Birula (1938), with some modifications by Gromov (2004).The terminology used for identifying teeth and other structures in the chelicerae follows Bird et al. (2015).Identification of individual teeth used Bird et al.'s criteria (2015) for primary homology assessment of dentition.The term 'ctenidia' stands for long, single-tipped (non-bifid) and flexible setiform structures present on some opisthosomal sternites.
The QIAGEN DNeasy Blood & Tissue Kit (Qiagen Inc., Valencia, CA) was used to extract genomic DNA from the muscle tissues of the legs for one male and one female of each species.The PCR primer for a partial fragment of the mitochondrial cytochrome oxidase subunit (COI) gene is the universal primer for invertebrate DNA barcoding LCO1490 and HCO2198 (Folmer et al. 1994).All sequences were analyzed using BLAST and are deposited in GenBank (Table 1).Sequence alignment was performed in MAFFT v. 7.313.The p-distance of intra-specific nucleotide divergence was calculated in MEGA.11.0.

Abbreviations as follows:
A/CP is the sum of the lengths of pedipalp, leg I, and leg IV divided by the sum of the lengths of chelicera and propeltidium, indicating the length of appendages in relation to body size.Long-legged species have larger A/CP ratios.CL/CH, chelicera length/height, large CL/CH ratios suggest a narrow cheliceral morphology, while a more robust morphology is represented by a smaller ratio.CL, chelicera length; CH, chelicera height; fcp (modified pvd), flagellar complex plumose setae; fcs, flagellar complex subspiniform to spiniform setae; FD, fixed finger, distal tooth; FM, fixed finger, medial tooth;
Propeltidium.Wider than long, with dense pubescence of thin, short, anteriorly directed setae.Anterior, posterior, and lateral edges with several long, curved spiniform setae perpendicular to the surface of the propeltidium.Ocular tubercle with two short and two long middle distal spiniform setae, one long middle spiniform setae, two short spiniform setae, and numerous shorter, thinner, proximal setae (Fig. 6A).
Chelicerae.Fixed finger primary teeth graded as FP ≈ FD < FM.Profondal teeth series with three tiny teeth; retrofondal teeth series with seven teeth.Dental formulation of fixed finger: FD-( 2 Opisthosoma.The entire surface covered with almost adpressed setae, and numerous long, curved, bifurcate setae.Sternite III with two posterior paramedian groups of ctenidia, being gradually larger to posterior (Fig. 19A); sternite IV with a row of 19 long and thin cylindrical ctenidia (Fig. 19C).
Pedipalps.Entirely covered with short setae and long, thick setae.Tarsus with ten ventral spines; metatarsus with six ventral spines not arranged in pairs and without papillae (Figs 16A,B).
Legs.Entirely covered with long, thick, setae and short setae.Leg I with no spines and two small claws.Tibiae II, III, and IV with a pair of distal spines ventrally, and tibiae II and III with a single dorsal spine.Metatarsus II and III with a series of three dorsal spines, a pair of distal spines ventrally, and some paired short, thick, spine-shaped bristles over their entire ventral surface; metatarsus IV also with these paired bristles over its entire ventral surface and two distal spines ventrally.
Coloration.In 75% ethanol-preserved specimens (Fig. 3C, D).Coloration as in the males.Propeltidium.Much longer than wide with a dense pubescence of thinner, short, anteriorly directed setae.Anterior, posterior, and lateral edges with several long, curved spiniform setae that are perpendicular to the surface of the propeltidium.Ocular tubercle with some long setae and numerous shorter, thinner setae (Fig. 6B).Opisthosoma.The entire surface covered with almost adpressed setae and numerous long, curved, bifurcate setae.Genital operculum long subtriangular and bottom widened (with lightly chitinized folds) between and behind them (Fig. 17A).Sternite IV with eight ctenidia on each side, for a total of 16 longer acicular ctenidia extending 1/2 length of the succeeding sternite (Fig. 18A).
Distribution and Habitat.China (Xizang).Habitat: high altitude meadow and semi-desert meadow.
Etymology.Noun in apposition taken from Dingye County where this species was collected.
Coloration.In 95% ethanol-preserved specimens (Fig. 3E, F).The general background brown-yellow.Opisthosoma pale yellow, with black tergites and pale black sternites.Propeltidium tinged with pale brown.Ocular tubercle black.Mesopeltidium and metapeltidium with special black stripes.Chelicerae with manus predominantly yellowish, with some black areas, and a retrolateral view of chelicerae with three black longitudinal stripes (paler than K. tibetana).Pedipalps and legs pale yellow, legs III and legs IV tinged with pale brown on distal regions of femora and proximal parts of tibiae.Proximal regions of the pedipalpal femur, tibia, metatarsus, and tarsus tinged with brown.Malleoli white.Opisthosoma.The entire surface covered with almost adpressed setae and numerous long, curved, bifurcate setae.Sternite III with two posterior paramedian groups of ctenidia, being gradually larger to posterior.(Fig. 19B); Sternite IV with 17 short peg-like ctenidia extending 1/4 the length of the succeeding sternite (Fig. 19D).
Pedipalps.Entirely covered with short setae and long, thick setae.Tarsus with eleven short, sturdy ventral spines; metatarsus with nine ventral spines not arranged in pairs and with thin papillae (Fig. 16C, D).
Legs.Entirely covered with long, thick setae and short setae.Leg I with no spines and two small claws.Tibias II, III, and IV with a pair of distal spines ventrally.Tibias II and III with a single dorsal spine; metatarsi II and III with a series of three dorsal spines, a pair of distal spines ventrally, and some paired short, thick, spine-shaped bristles over their entire ventral surface.Metatarsus IV also with these paired bristles over its entire ventral surface and two distal spines ventrally.
Propeltidium.Much wider than long with a dense pubescence of thin, short, anteriorly directed setae.Anterior, posterior, and lateral edges with several long, curved spiniform setae that perpendicular to the surface of the propeltidium.Ocular tubercle with four middle distal spiniform setae, covered with some long setae and numerous shorter, thinner setae (Fig. 6D).
Opisthosoma.The entire surface covered with almost adpressed setae and numerous long, curved, bifurcate setae.The bottom of the genital operculum slightly widened, resembling a trapezoid (Fig. 17B).Sternite IV with 19 short spine-like ctenidia extending from the edge of sternite IV (Fig. 18B).
Pedipalps.Entirely covered with short setae and long, thick setae and without spines.
Etymology.Noun in apposition taken from Lhasa City where this species was collected.
Diagnosis.Karschia lhasa sp.nov.differs from all Karschia species except K. zhui sp.nov.by cheliceral fixed finger mucron having dorsal crest (Fig. 11C).K. lhasa sp.nov.differs from K. zhui sp.nov.by cheliceral fixed finger mucron crescent-shaped dorsal crest broader (Fig. 11C), and pedipalp having more spines and thick papillae (Fig. 16H).The female genital operculum is easily recognizable when compared to that of other species; it has a clear demarcation between the plates.and resembles a fan-shaped structure.(Fig. 17C).
Coloration.In 75% ethanol-preserved specimens (Fig. 4A, B).The general background pale yellow.Opisthosoma grey-yellow, with black tergites and pale black sternites.Propeltidium tinged pale brown.Ocular tubercle black.Mesopeltidium and metapeltidium with special black stripes.Chelicerae with manus predominantly brown-yellow, with some black areas, and a retrolateral view of chelicerae with three black longitudinal stripes.Pedipalps and legs yellow, legs III and legs IV tinged with pale brown on distal regions of femora and proximal parts of tibiae.Proximal regions of the pedipalpal femur, tibia, metatarsus, and tarsus tinged with brown.Malleoli yellow.
Propeltidium.Slightly wider than long with a dense pubescence of thin, short, anteriorly directed setae.Anterior, posterior, and lateral edges with several long, curved spiniform setae that perpendicular to the surface of the propeltidium.Ocular tubercle with one short and four long middle distal spiniform setae, one long median spiniform setae, two shorter posterior spiniform setae, and numerous short, thin posterior setae (Fig. 6E).
Pedipalps.Totally covered with short setae and long, thick setae.Tarsus not swollen with five sturdy ventral spines; metatarsus with eight ventral spines not arranged in pairs and with thick papillae (Fig. 16E, F).
Legs.Totally covered with long, thick setae and short setae.Leg I with no spines and two small claws.Tibias II, III, and IV with a pair of distal spines ventrally.Tibias II and III with a single dorsal spine.Metatarsi II and III with a series of three dorsal spines, a pair of distal spines ventrally, and some paired short, thick, spine-shaped bristles over their entire ventral surface; metatarsus IV also with these paired bristles over its entire ventral surface and two distal spines ventrally.
Coloration.In 75% ethanol-preserved specimens (Fig. 4C, D).Coloration as in the males.Propeltidium.Much wider than long with a dense pubescence of thin, short, anteriorly directed setae.Anterior, posterior, and lateral edges with several long, curved spiniform setae that perpendicular to the surface of the propeltidium.Ocular tubercle with four middle distal spiniform setae, two middle spiniform setae, and two posterior spiniform setae (Fig. 6F).
Opisthosoma.The entire surface covered with almost adpressed setae and numerous long, curved, bifurcate setae.The bottom of the genital operculum slightly widened, resembling a fan-shaped structure (with chitinized folds) between and behind it (Fig. 17C).Sternite IV with 13 long needle-like ctenidia extending 3/4 the length of the succeeding sternite (Fig. 18C).
Pedipalps.Totally covered with short setae and long, thick setae without spines.
Coloration.In 95% ethanol-preserved specimens (Fig. 4E, F).The general background pale yellow.Opisthosoma brow yellow, with black tergites and pale black sternites.Propeltidium black tinged with pale brown.Ocular tubercle black.Mesopeltidium and metapeltidium with special black stripes.Chelicerae with manus predominantly yellowish, with some black areas, and a retrolateral view of chelicerae with three black longitudinal stripes.Pedipalps and legs pale brown-yellow, legs III and legs IV tinged with pale brown on distal regions of femora and proximal parts of tibiae.Proximal regions of the pedipalpal femur, tibia, metatarsus, and tarsus tinged with brown.Malleoli white.
Propeltidium.Wider than long with a dense pubescence of thin, short, anteriorly directed setae.Anterior, posterior, and lateral edges with several long, curved spiniform setae that perpendicular to the surface of the propeltidium.Ocular tubercle with four middle distal spiniform setae, one middle spiniform setae, and two proximal spiniform setae (Fig. 7A).
Chelicerae.Fixed finger primary teeth graded as FP < FM ≈ FD.Profondal teeth series with four or five tiny teeth; retrofondal teeth series with six teeth.Dental formulation of fixed finger: FD-(2)-FM-(2)-FP-(6RF) (4PF).Fixed finger mucron with crescent-shaped dorsal crest smaller than K. lhasa.Movable finger MP tooth about the same size as MM.Dental formulation of movable finger: MM-(1)-MP, with one tiny MSM and three MSP (Figs 9E, 14E).Flagellum coiled, fringed and sessile, without lateral apophysis.The flagellar complex includes two medium length fcp and two short, thick fcs.(Figs 9E,11D,14F).Retrolateral and dorsal surfaces of the manus with large, bifurcated tip setae and short, simple tip bristle-like setae; retrolateral and dorsal surfaces of the fixed finger with simple tip setae of different sizes.Retrolateral setose area reaching the FSM teeth; prolateral surface with an array of setal types (Figs 9E,F,14E,F).
Opisthosoma.The entire surface covered with almost adpressed setae and numerous long, curved, bifurcate setae.Sternite III with a row of disordered ctenidia (Fig. 19F).Sternite IV with 16 long peg-like ctenidia, the length of which almost equal to 1/2 the width of the succeeding sternite (Fig. 19H).
Pedipalps.Totally covered with short setae and long, thick setae.Tarsus with nine sturdy ventral spines; metatarsus with 11 ventral spines not arranged in pairs and with thick papillae (Fig. 16G, H).
Legs.Totally covered with long, thick setae and short setae.Leg I with no spines and two small claws.Tibias II, III, and IV with a pair of distal spines ventrally.Tibias II and III with a single dorsal spine; metatarsi II and III with a series of three dorsal spines, a pair of distal spines ventrally, and some paired short, thick,
Coloration.In 95% ethanol-preserved specimens (Fig. 5A, B).The general background pale yellowish.The opisthosoma slightly darker, with black tergites and yellow around the black sternites.Propeltidium pale tan and tinged with pale brown.Ocular tubercle black.Mesopeltidium and metapeltidium with special black stripes.Chelicerae with manus predominantly yellowish, with some black areas, and a retrolateral view of chelicerae with three black longitudinal stripes.Pedipalps and legs pale yellow, legs III and legs IV tinged with pale brown on distal regions of femora and proximal parts of tibiae.Proximal regions of the pedipalpal femur, tibia, metatarsus, and tarsus tinged with brown.Malleoli yellow.Propeltidium.Wider than long with a dense pubescence of thin, short, anteriorly directed setae.Anterior, posterior, and lateral edges with several long, curved spiniform setae that perpendicular to the surface of the propeltidium.Ocular tubercle with two middle distal spiniform setae and one middle spiniform setae (Fig. 7C).Chelicerae.Fixed finger primary teeth graded as FP < FD < FM.Profondal teeth series with three tiny teeth; retrofondal teeth series with seven teeth.Dental formulation of fixed finger: FD-( 2 Opisthosoma.Entire surface covered almost adpressed setae, and numerous long, curved, bifurcate setae.Sternite III with 21 pine needle-like ctenidia (Fig. 19I).Sternite IV with 15 long peg-like ctenidia, the length of which almost equal to half the width of the succeeding sternite (Fig. 19K).
Pedipalps.Totally covered with short setae and long, thick setae.Tarsus with eight sturdy ventral spines; metatarsus with 10 ventral spines not arranged in pairs and with thin papillae (Fig. 16I, J).
Legs.Totally covered with long, thick setae and short setae.Leg I with no spines and two small claws.Tibias II, III, and IV with a pair of distal spines ventrally.Tibias II and III with a single dorsal spine; metatarsi II and III with a series of three dorsal spines, a pair of distal spines ventrally, and some paired short, thick, spine-shaped bristles over their entire ventral surface.Metatarsus IV also with these paired bristles over its entire ventral surface and two distal spines ventrally.
Propeltidium.Much wider than long with a dense pubescence of thin, short, anteriorly directed setae.Anterior, posterior, and lateral edges with several long, curved spiniform setae that perpendicular to the surface of the propeltidium.Ocular tubercle with four middle distal spiniform setae and three middle spiniform setae arranged in a triangle shape (Fig. 7E).Opisthosoma.The entire surface covered with almost adpressed setae and numerous long, curved, bifurcate setae.Genital operculum equilateral subtriangular and with no clear demarcation between the plates.The rear edge of the genital sternite not chitinized (Fig. 17E).Sternite IV with 17 long needle-like ctenidia extending a half of the length of the succeeding sternite (Fig. 18E).
Pedipalps.Totally covered with short setae and long, thick setae and without spines.
Etymology.Noun in apposition taken from Namling County, where this species was collected.
Opisthosoma.The entire surface covered with almost adpressed setae and numerous long, curved, bifurcate setae.Genital operculum triangular in shape with no clear demarcation between the plates., and the rear edge of the genital sternite not chitinized (Fig. 17F).Sternite IV with 14 short needle-like ctenidia extending 1/3 the length of the succeeding sternite (Fig. 18E).
Remark.Based on the comparison of genetic distances, with a genetic distance of 0% (Table 2) between male and female collected from same locations, we believe that they are same species.

Discussion
The cytochrome c oxidase subunit I (COI) gene has been extensively employed in taxonomic and differentiation studies of Arachnida species.Analysis of COI sequences enables researchers to deepen their understanding of genetic variances among various species, thus facilitating more precise delineation and differentiation (Maddahi et. al. 2016).
The rich diversity of Karschia in Xizang can be ascribed to its distinctive geographical environment and climate conditions.With an average elevation surpassing 4000 meters, Xizang features vast high-altitude lakes and intricate geographical terrain, which hinder species dispersal, resulting in geographic isolation.Furthermore, we documented the highest Solifugae record (K. shigatse sp.nov.) in the Old World, complete with precise geographic coordinates, at an elevation of 4605.8 meters.
After examining various taxonomic characteristics of solifuge species and comparative specimens in this research, we think cheliceral teeth possess some taxonomic value, particularly regarding the relative size between the primary teeth of the median teeth series, which remains constant: the fondal series typically exhibit variability, and the numbers of secondary teeth generally have poor taxonomic value unless a specific type of tooth is entirely missing.Body size and coloration are subject to variation, with the opisthosoma being relatively soft and its size susceptible to change based on the nutritional state of the specimen; coloration can fluctuate with environmental changes, indicating that these traits have limited taxonomic value.The numbers of ctenidia on the sternite and spines of the male pedipalp also display variation, albeit to a lesser extent, making them suitable as additional diagnostic characters; however, the shape and size of ctenidia on the sternite are relatively constant, rendering them reliable taxonomic characteristics.The study confirms the significance of the female genital operculum in classification, as the shape, size, and relative arrangement of the genital operculum remain consistent among female individuals of the same species; the flagellar complex of the male serves as reliable diagnostic characteristics, particularly regarding the degree of modification of the fcp (flagellar complex process plumose setae), the shape and number of fcs (flagellar complex subspiniform to spiniform setae), and the lateral apophysis.
Reevaluating the taxonomy of numerous Karschiidae species is indeed crucial and urgent.Historically, their classification and diagnostic criteria have heavily leaned on the cheliceral teeth traits of only a limited number of female specimens (Birula 1922(Birula , 1938;;Roewer 1933Roewer , 1934)).However, this approach may not fully capture the diversity and variation present within these species.Therefore, a more comprehensive assessment that considers a broader range of taxonomic characters, including those mentioned earlier such as the shape and numbers of ctenidia on the sternite and the shape and size of the genital operculum in females, is necessary.By incorporating these additional diagnostic characteristics, we can better elucidate the taxonomy and improve our understanding of the intricate relationships among Karschia species.
)-FM-(2)-FP-(7RF) (3PF).Movable finger MP tooth about the same size as MM.Movable finger dental formula: MM-(2)-MP, with two MSM teeth and two MSP (Figs 8A, 13A).Flagellum coiled, fringed and sessile, without lateral apophysis.The flagellar complex includes two long fcp and two short, thick fcs (Figs 8B, 11A, 13B).Retrolateral and dorsal surfaces of the manus with large, bifurcated tip setae and short simple tip bristle-like setae; retrolateral and dorsal surfaces of the fixed finger with simple tip setae of different sizes.Retrolateral setose area reaching the FSM teeth; prolateral surface with an array of setal types (Figs 8A, B, 13A, B).
)-FM-(1)-FP-(6RF) (3PF).Fixed finger mucron with wider and crescent-shaped dorsal crest.Movable finger MP tooth about the same size as MM.Dental formulation of movable finger: MM-(2)-MP, with one tiny MSM and four MSP (Figs 9A, B, 14A, B).Flagellum coiled, fringed and sessile, without lateral apophysis.The flagellar complex includes two medium length fcp and two short, thick fcs (Figs 9B, 11C, 14B).Retrolateral and dorsal surfaces of the manus with large, bifurcated tip setae and short, simple tip bristle-like setae; retrolateral and dorsal surfaces of the fixed finger with simple tip setae of different sizes.Retrolateral setose area reaching the FSM teeth; prolateral surface with an array of setal types (Figs 9A, B, 14A, B).
)-FM-(2)-FP-(7RF) (3PF).Fixed finger mucron without dorsal crest.Movable finger MP tooth about the same size as MM.Dental formulation of movable finger: MM-(2)-MP, with two tiny MSM and three MSP (Figs 10A, 15A).Flagellum coiled, fringed and sessile, with lateral apophysis.The flagellar complex includes two medium length fcp and two short, thick fcs (Figs 10B, 11E, 15B).Retrolateral and dorsal surfaces of the manus with large, bifurcated tip setae and short, simple tip bristle-like setae; retrolateral and dorsal surfaces of the fixed finger with simple tip setae of different sizes.Retrolateral setose area reaching the FSM teeth; prolateral surface with an array of setal types (Figs 10A, B, 15A, B).

Table 2 .
Genetic distance among the six species. K.