Langxie feti, Tang & Jia & Liu, 2023

Tang, Victoria, Jia, Qingquan & Liu, Leonhard, 2023, A new monotypic genus and species from China Langxie feti gen et sp. n. (Scorpiones: Buthidae), Euscorpius 370, pp. 1-101 : 20-31

Langxie feti gen. et sp. n.

( Figures 1–63 , 65 , 82–155 ; Tables 1–3) http: //zoobank. org/urn: lsid: zoobank. org: act: 02E49E59-

799C-4775-8AB1-FF973F28BF5D

TYPE LOCALITY AND TYPE REPOSITORY. China, Xizang Autonomous Region (Tibet Autonomous Region), Linzhi ( Nyingchi ) Prefecture , Chayu (Zayü) County, Gula (Golag) Township (the entire region; 古Ü乡 in Chinese ), ca. 29°12'91''N 97°57'73''E, ca. 2429 m a. s. l.; VT .

TYPE MATERIAL. China, Xizang Autonomous Region (Tibet Autonomous Region), Linzhi ( Nyingchi ) Prefecture , Chayu (Zayü) County, Gula (Golag) Township (the entire region), ca. 29°12'91"N 97°57'73"E, ca. 2429 m a. s. l., 14–16 September 2022, 1♂ (holotype) 16♂ 42♀ 4♀ juvs (paratypes), leg. Qingquan Jia. Holotype and most of paratypes are in VT; 1♂ 1♀ (paratypes) are in BMNH; 5♂ 5♀ (paratypes) are in František Kovařík ( FKCP), Graeme Lowe, Ersen Aydın Yağmur and Rolando Teruel personal collections.

ETYMOLOGY. The specific epithet is a patronym in honor of Victor Fet (Marshall University, USA), who has always been very supportive and encouraging to the first author in all aspects. Chinese equivalent. Î氏ffiffl (roughly as “Fet’s wolf scorpion” in English; see Tang (2022a) for the rules of designation).

DIAGNOSIS. As for the genus.

DESCRIPTION (based on holotype male and paratype female). Photographs of the specimens in Figs. 1–4 were taken under white light. Photographs of the specimen in Figs. 5–57 were taken under UV light so as to depict the surface morphosculpture (granulations and carinae). UV photographs are more informative about the external structural morphology; coloration is referable in Figs. 62–63 , 82a–f , 85a–f and Appendix. Due to the lack of live specimens, the holotype and paratype were selected from the specimens preserved in ethanol for about 4 months (see Acknowledgement), thus no in vivo photographs of details under white light were taken. The coloration description was instead based on other photographs taken when specimens were still alive ( Figs. 82a–f ).

Coloration (in vivo) ( Figs. 82a–f ). General coloration yellowish brown to blackish brown. Dorsal surface of chelicerae brownish and reticulated. Base color of carapace, tergites, metasoma and pedipalp (except for chela) yellowish brown. Pedipalp manus and tip of finger whitish yellow, same color as base of trochanter of pedipalp and leg. Base color of leg darkens gradually towards basitarsus from femur. Dark colors form maculated patterns on carapace, pedipalps (except for chela) and legs (less variegated on trochanter and telotarsus), inconspicuous in dry live specimens. Posterior margin of each tergite generally darker than anterior region, but anterior region still variegated with markings axial symmetrically. Brownish streaks of variable color present along carinae of metasoma and base color darkens towards the fifth segment (gradually changes color from yellowish brown to reddish black from posteriorly). Darkest areas often concentrated in pedipalp chelal finger (base to medial part), pedipalp patella, anterior margin of carapace, median ocular region, and posterior region of the 5 th metasomal segment. Femur and patella of each leg sometimes slightly darker than tergites, but anterior carapacial margin and pedipalp patella (and sometimes the fifth metasomal segment) always represent the darkest area. Ventral side of prosoma semitranslucently light brownish yellow, color saturation level of 2 nd coxapophyses higher than surrounding area. Pectines, posterior bands of the first four sternites (anterior area almost completely translucent) and book lungs whitish yellow. Telson orange red to reddish brown (may be relevant with age; can be yellowish in juveniles), except for aculeus which is black.

Prosoma ( Figs. 5 , 7 , 9–12 ). Carapace generally flat, isosceles trapezoidal, slanting laterally with shallow grooves; anterior margin concave (triangularly incised) and thickened (weakly raised) until the posterior end of each lateral ocular carina, with four evenly positioned setae. Dorsal surface highly granulated, granules do not form conspicuous carinae, except for a pair of posterior median carinae weakly to moderately indicated; superciliary carinae weakly present, without granules in between; interocular distance approximates or is greater than diameter of one median ocellus. Intergranular surfaces either smooth or scrobiculate (present as lattice microstructures, never on granules/carinae), but both types of areas scattered axial symmetrically throughout the entire dorsal surface. Five pairs of lateral eyes, three major ocelli, two minor ocelli; PDMi posterior to PLMa, ADMi smaller and above PLMa (posterior to lateral ocular carina); posterior area of each group of lateral eyes on dorsal surface of carapace shallowly depressed and smooth. Ventral surface of prosoma smooth. Sternum type 1, sub-triangular in shape. Genital operculum medially separated with two macrosetae on each half near the posterior margin. Pectines with three marginal lamellae equipped with moderate length setae laterally, 1 st (basal) lamella conspicuously longer than the other two, 2 nd (medial) and 3 rd (distal) lamellae similar in length; one small piece presents between basal and medial marginal lamella; median lamellae subdivided into usually 7–9 pieces, scattered with short setae; pectinal fulcra strongly developed, scattered with short setae; pectinal teeth number 20– 19 in holotype male and 18– 18 in paratype female; sensorial area located anteriorly on each tooth, slender in male.

Mesosoma ( Figs. 6 , 8 , 13–14 ). Tergites highly granulated, with size of granules and intensity increasing successively. One median carina composed of relatively small granules, flanked with a pair of shallow, smooth, oval depressions anteriorly, starting from the 2 nd tergite. Boundary between pretergite and posttergite pleated and undulate. 7 th tergite with additional two pairs of strongly developed carinae connected to the posterior margin; median carina on this tergite fades out medially. Ventral surface of mesosoma smooth, except for sternite VII with four carinae (the two in middle more prominent) and moderately granulated. Previous sternites glossy with posterior margins undulate; lateral margins of sternites to V–VII serrated. Spiracles located near the posterior corner of sternites; small, slit-like, posterior area with lattice microstructures.

Chelicerae ( Figs. 23–26 ). Chelicerae with typical buthid dentition, basal and median denticle forming a bicuspid on fixed finger which is armed with one enlarged accessory denticle ventrally; movable finger with dorsal distal, subdistal, median and basal (bicuspid) denticles dorsally, one ventral distal denticle and 2–3 ventral accessory denticles ventrally. Fixed finger with long, fine, curved (appearing soft) setae ventrally, manus with few, fine, sublinear setae on fixed finger dorsally and long, fine, sublinear setae ventrally, concentrated on the area beneath fixed finger; internal margin of manus equipped with numerous long, thick, dark, nearly straight setae ventrally but fine, short setae dorsally; ventral surface with single accessory denticle.

Metasoma and telson ( Figs. 15–22 ). Entire metasoma and telson glabrous but granular. Metasomal segments slender and increase in length posteriorly; I–II with 10 carinae (dorsosubmedian, dorsolateral, median lateral, ventrolateral and ventrosubmedian, all in pairs), III–IV with 8 carinae (dorsosubmedian, dorsolateral, ventrolateral and ventrosubmedian, all in pairs), V with 5 carinae (dorsolateral and ventrolateral in pairs, and one single ventromedian); all carinae strongly developed and costate-granular, becoming more granular towards dorsal surface and more costate towards ventral surface. Median lateral carina on metasomal segment II become vestigial proximally; this carina is replaced by scattered series of granules that do not form distinct carinae on subsequent metasomal segments. Dorsosubmedian and dorsolateral carinae of metasomal segments I–III terminate in a tooth which is relatively enlarged. Granule density of ventral surface higher than that of lateral surface which is higher than that of dorsal surface. Granule intensity of dorsal surface between dorsosubmedian carinae decreases from metasomal segment I to III. Dorsal surface of metasomal segment IV shows two inconspicuous series of granules between dorsosubmedian carinae; similar series pair also exists on dorsal surface of metasomal segment V. Anal arch without prominent lobes; ventral margin of anal arch nearly straight, equipped with four evenly spaced setae. Telson weakly granulated, elongate, ellipsoidal in shape, bilaterally with shallow sulci and one carina comprised of small granules. Subaculear tooth distinct, triangular, sometimes with a secondary tubercle on dorsal surface. Ventral surface of telson and subaculear tooth with fluorescent setae, moderate in length; dorsal surface with short, fluorescent setae; few additional non-fluorescent macrosetae present on subaculear tooth, middle range and proximal end of ventral surface. Aculeus moderately curved and long, approximating the length of vesicle.

Pedipalps ( Figs. 27–46 ). Pedipalps slender and glabrous; short, fluorescent setae dominate, but longer, non-fluorescent setae also present; patella wider and relatively longer than femur. Orthobothriotaxic, type Aβ, femur trichobothrium d 2 prolateral to prodorsal carina, close to i 1-4 series, patella d 3 between retrodorsal and dorsomedian carina, close to latter; periphery of each trichobothrium on femur and patella locally appearing brighter in fluorescence intensity under UV light. Femur with five granulated carinae, intercarinal surfaces with small granules and lattice microstructures; proventral carinae weakest, prodorsal and retrodorsal carinae well developed with fine granules, promedian and retromedian carinae indicated by larger granules. Patella with seven weaker carinae, intercarinal surfaces with lattice microstructures; promedian carinae formed by moderate granules, prodorsal and dorsomedian carinae formed by fine granules, other carinae smooth. Pedipalp chela slender, with smooth carinae which may be discernible throughout the length of the fixed finger; chelal finger conspicuously longer than manus (ca. 2 times), weakly curved inwardly and upwardly. Fixed finger with 7 oblique rows of MDs; row 1 to 5 gradually increase in length proximally and slightly curve externally when approaching the final MD; row 6 and 7 similar in length and together form a linear arrangement; one IAD proximally flanks row 1 to 6 respectively, EAD absent from all rows. Movable finger comprises 6 oblique rows of MDs that successively increase in length proximally; row 1 to 5 end in a moderately enlarged MD proximally which is flanked by an IAD but lacks an EAD; row 6 obviously longer than previous rows, without EAD along its length and is not flanked by an IAD, apical row anterior to the 1 st row very short, composed of less than 5 subterminal denticles, distal end flanked by one or two terminal denticles.

Legs ( Figs. 47–54 ). Weak, smooth carinae comprised of small granules present from femur to basitarsus. Tibial spurs of leg III and IV similar in length and shape, both short and reduced. Femur and patella with only a few setae; setal density increases from tibia to telotarsus retrolaterally and ventrally; tibia and tarsus without bristle combs, most setae on tibia similar in length, retrolateral setae relatively longer than ventral setae on basitarsus, distal setae conspicuously longer than ventral setae on telotarsus; basitarsus and telotarsus with two rows of ventral setae. Tarsal ungues curved and stout; two pedal spurs and one dactyl on each leg, short and stout.

Measurements. See Table 1.

Variation (see Appendix, Figs. 90–155 ). As mentioned above, there is variation among different individuals in both the overall coloration and the coloration of telson. Some individuals, presumably older, are blackish brown with dark red telson, while others are yellowish brown, especially their tergites. For PTC, among the 109 pectines enumerated, 33 belong to male specimens. In these male specimens, 2 pectines were recorded with 18 teeth, 11 with 19, 14 with 20 and 6 with 21. In the remaining female specimens, 9 pectines were recorded with 16 teeth, 21 with 17, 35 with 18, 10 with 19 and 1 with 20. In one female specimen, a basal tooth was found to be dilated and appeared to be a result of incomplete partition ( Fig. 57 ). Granulation and carination on the carapace may vary, but neither of them was found to be consistently related to certain development stages. There is also a variation regarding the relative slenderness of the pedipalp chela finger, and the relative width and length of the pedipalp chela manus with respect to the fingers, but no consistent positive correlations with other features (e. g., body size, 5 th metasoma, telson) were found. Variation in body size was found in both adult males and adult females ( Figs. 62–63 ). It is interesting to note that although two different adult female specimens were similar in terms of the telson size, the relative ratio of their 5 th metasoma sizes can be different; usually, larger females have more slender 5 th metasoma.

Statistic p-value

ROI area 7.33e +8 <0.001

ROI Feret's diameter 7.37e +8 <0.001

Note. H ₐ μ Female <μ Male

DISTRIBUTION ( Fig. 86 ). Known only from the southeast region of the Tibet Autonomous Region in China, and at least had been recorded in two townships, Chawalong (Cawarong or Tsawarong) and Gula (Golag), both close to the border between Xizang and Yunnan Provinces.

ECOLOGY. The new species is extremely abundant in the region (Gula Township; Figs. 83a–f ) and nearly 400 specimens were discovered on three nights (14–16 September; no early instar individuals were found at this period of time). Most of the specimens were found hiding in rock crevices or wandering on walls of the flood embankment slope, as well as in the nearby rocky grassland ( Figs. 84a–f ). The elongation and slenderization of appendages and metasoma are probably an adaptation to the crevice microhabitat. The habitat and habitus of the new species are consistent with the lapidicolous ecomorphotype (sensu Prendini, 2001), or the lithophilous ecomorph (sensu Coelho et al., 2022). Scorpions became active after 21:00 pm, and they were found to be feeding on a variety of prey, including crickets, spiders, scutigerids, and hemipterans, clinging on the stone wall and facing downwards ( Figs. 85a–f ). The new species also exhibited a rapid escape response with high velocity of locomotion. Regarding the surrounding environment, a river (presumably a tributary of the Nu River) flows through the Gula Township and dense vegetation is found on both of the river banks. This may have provided sufficient humidity to the region to make it a favorable habitat for this scorpion. Under captive environments, this species demonstrates high tolerance towards other conspecifics when kept in a community. It exhibits positive thigmotaxis and an escape response can be easily evoked by a single tactile stimulation or a flipping of shelter. It is observed that this species will quickly seek narrow shelters once they find themselves exposed to bright light.

Conservation status. Only two scorpion species are regionally protected in China: Mesobuthus thersites (C. L. Koch, 1839) and Olivierus martensii (Karsch, 1879) . Little is known about the authentic distribution range of the new genus, therefore the evaluation for its conservation status is undecided. Scorpions recorded in the adjacent region belong to the genus Scorpiops and it seems that those scorpions have been negatively affected by anthropic activities as few species had been found since their initial description (Zhiyong Di, pers. comm.). However, the errant species of Buthidae are not soil-dependent and they may show a higher level of dispersal ability. Furthermore, the current study discovered an extremely high density of this species within a small region, and the geography of Tibet Autonomous Region can prevent the excessive hunting targeted at this species (entry is difficult). Local residents also showed great respect to those animals due to their religious beliefs. The Tibetan people do not kill animals unless necessary, and they also protect them, living in harmony with those wild species in nature. The protection of this species is nonetheless recommended until its population is fully studied.

Figures

Figures 82a–f. Langxie feti gen. et sp. n., in vivo, live paratypes females (82 a, c, d, e) and males (probably subadult, 82b and 82f).

Figures 83a–f. Gula Township, type locality of Langxie feti gen. et sp. n.

Figures 84a–f. Habitat of Langxie feti gen. et sp. n.

Figures 85a–f. Topotypes of Langxie feti gen. et sp. n. observed feeding on different preys in the wild at night.

Figures 86–87: Figure 86. Map showing the representative localities of the discussed species. Langxie feti gen. et sp. n. (★, Gula (Golag) Township, type locality in TibetAutonomous Region, China), Langxie cf. feti gen. et sp. n. (★, Chawalong (Cawarong or Tsawarong) Township, locality in Tibet Autonomous Region, China); Lychas mucronatus (▲, the north-most record in Deqin County of Yunnan Province, China; for other localities, see Tang 2022c); L. brehieri (▲, “Saddan Sin Gu” Cave, type locality in Myanmar); L. gravelyi (▲, Mawlamyine (“Moulmein”), type locality in Myanmar); L. scutilus (▲, Maliwan Village, the only known locality in Myanmar); Afrolychas braueri (■, Praslin Island, type locality in Seychelles); A. burdoi (■, Zanzibar, type locality in Tanzania); Himalayotityobuthus alejandrae (●, north of Saharanpur, type locality in India, approximated from fig. 16 in Lourenço (2003)); H. martensi (●, Tangmarg (left), type locality in India, and locality (“Tribani Ghat”, Lourenço, 1997) in Nepal, approximated from fig. 16 in Lourenço (2003); it appears that “Tribani Ghat” should instead be “Triveni Ghat” (○) in India or “Tribeni” in Nepal (●)). Figures 87a–b: Morphometric analyses of potential sexual dimorphisms among all the adult females and males (one injured adult female excluded; paratype, no. F8). Figure 87a. Bivariate scatter plot comparing ratiometrics regarding pectine length/ metasoma I width (abscissa) vs. pectine length/carapace width (ordinate). Only one pectine of each specimen was examined (the most ideal one, i.e., less deformed). The manual measurement upon these tiny structures can easily arouse errors and deformation of specimens may cause anomalies, thus this result is only referential for the general trend.Figure 87b. Bivariate scatter plot comparing ratiometrics regarding longitudinal diameter of median ocelli/carapace length (abscissa) vs. latitudinal diameter of median ocelli/carapace width (ordinate); normalized in pixels (another female paratype, no. F17 with obvious carapace deformation was excluded).

Figures 88–89: Figures 88a–h: Exemplary procedures of granulometric analysis using ImageJ on a full resolution image of a single carapace. The results of automated computer analysis differ from those obtained by human recognition and delimitation of granule shapes, but are sufficient to resolve sexual dimorphism. Figure 88a. Original carapace image acquired under UV fluorescence. Figure 88b. Carapace surface manually cropped from original image, with brightness and contrast adjusted. Figure 88c. Carapacial margins manually erased to exclude marginal granulation.Figure 88d. Image filtered with a low-pixel Gaussian blur (6-pixel radius) acting as a low-pass filter to suppress digital image noise and minute surface textures (e.g., lattice microstructures) (this step is unnecessary for Fig.91 which already has a lower resolution).Figure 88e. Image filtered again with a higher-pixel Gaussian blur (20-pixel radius), acting as a low pass filter to suppress granules. Figure 88f. Image obtained by subtracting the second filtered image (88e) from the first (88d) to emphasize the granules by removing larger scale background intensity trends; brightness and contrast adjusted.Figure 88g. Result of applying an automatic thresholding algorithm (Yen method).Figure 88h. Particles detected in the thresholded image, under the criteria: area = 7–2,000 pixel2, circularity = 0.50–1.00. Figure 89. Comparison of ROIs retrieved by automatic detection method (left) and manually generated granule profiles estimated by human visual perception and interpretation of the UV fluorescence image (right).

Figure 90. Habitus of all the type specimens of Langxie feti gen. et sp. n.; specimens are placed in the same sequence as the subsequent order of each specimen (start from above to below and left to right (same for all rows of specimens)).

Figure 91. Compilation of carapace morphology of all the types of Langxie feti gen. et sp. n. (first four are juveniles, others are females and last 17 are males).

Figures 1–4: Langxie feti gen. et sp. n., habitus under white light. Figures 1–2. Male holotype in dorsal (1) and ventral (2) views. Figures 3–4. Female paratype in dorsal (3) and ventral (4) views. Scale bar = 10 mm.

Figures 5–6. Langxie feti gen. et sp. n., carapace of female paratype (5) and male holotype (6) under UV light.

Figures 7–8. Langxie feti gen. et sp. n., tergites of female paratype (7) and male holotype (8) and under UV light.

Figures 9–12: Langxie feti gen. et sp. n., coxal and sternopectinal regions (9, 11) and pectines in dorsal aspect (10, 12) under UV light (figures of left and right pectines in dorsal aspect mirrored to directly match the ones in ventral aspect in their above figures). Figures 9–10. Male holotype. Figures 11–12. Female paratype.

Figures 13–14: Langxie feti gen. et sp. n., sternites under UV light. Figure 13. Male holotype. Figure 14. Female paratype.

Figures 15–22: Langxie feti gen. et sp. n., metasoma and telson under UV light. Figures 15–18. Male holotype, metasoma and telson lateral (15), dorsal (16), and ventral (17) and telson lateral (18). Figures 19–22. Female paratype, metasoma and telson lateral (19), dorsal (20), and ventral (21) and telson lateral (22).

Figures 23–26: Langxie feti gen. et sp. n., chelicera in dorsal (23, 25) and ventral (24, 26) views under UV light. Figures 23–24. Male holotype. Figures 25–26(change). Female paratype.

Figures 27–28: Langxie feti gen. et sp. n., pedipalp movable (27a–27b) and fixed (28a–28b) fingers under UV light. Figures 27a–28a. Male holotype. Figures 27b–28b. Female paratype.

Figures 29–46. Langxie feti gen. et sp. n., pedipalp segments of male holotype (29–37) and female paratype (38–46) under UV light. Chela, dorsal (29, 38), external (30, 39) and ventral (31, 40) views. Patella, dorsal (32, 41), external (33, 42) and ventral (34, 43) views. Femur and trochanter, dorsal (35, 44), external (36, 45) and ventral (37, 46) views. The trichobothrial pattern is indicate in Figures 30–33, 35, 39–42, 44 (red circles).

Figures 47–54: Langxie feti gen. et sp. n., right legs I–IV of male holotype (47–50) and female paratype (51–54), retrolateral aspect, under UV light.

Figures 55–57: Langxie feti gen. et sp. n. Figures 55–56. Paratypes female (55) and male (56), sternopectinal areas under white light. Explanation of color markings (55–56): green, distance between left and right basal pectinal teeth; purple, posterior margin of sternite; red, comparison between pectinal tooth length and pectinal lamella width; yellow, boundary between 2nd and 3rd marginal lamellae; dark blue, distance between tip of pectine and trochanter-coxa joint; bright blue, external length of coxa. Figure 57. Paratype female, a single observed case of a dilated (incompletely separated, see red arrow) pectinal tooth.

Figures 58–61: Genital organs of Langxie feti gen. et sp. n. of under white light.Figures 58. Partially damaged hemispermatophores retrieved from an adult male (paratype no. M10). Figure 59. Ovariuterus partially revealed from an adult female (paratype no. F35). Figures 60–61. Removal of genital opercula of an adult male (60) and an adult female (61) paratypes; left genital papilla of the adult male fluoresces under UV light.

Figures 62–63: Langxie feti gen. et sp. n., intraspecific variation. Figure 62. Comparison between the smallest (paratype no. M12) and the largest males (paratype no. M17). Figure 63. Comparison between females (paratypes nos. F31, F40, F18, F4, left to right, and bottom); ovariuterus was not subsequently revealed from the bottom female (F4), and it was then presumed to be immature and its value was not

Figures 64–72. Lattice microstructure comparison among Alayotityus sierramaestrae Armas, 1973 (female, 64; photograph by G. Lowe), Langxie feti gen. et sp. n. (female, paratype, 65), Janalychas tricarinatus (Simon, 1884) (female, 66), Lychas scutilus C. L. Koch, 1845 (juvenile, 67), Lychas mucronatus (Fabricius, 1798) (female, 68, and male, 69), Tityus footei Chamberlin, 1916 (male, 70), Tityus stigmurus (Thorell, 1876) (female, 71) and Tityus smithii Pocock, 1893 (female, 72).