Chilobrachys qishuoi Lin & Li, 2022

Lin, Ye-Jie, Li, Shuqiang & Xie, Chunyan, 2022, A new species of Chilobrachys (Araneae, Theraphosidae) from Guangdong, China, Biodiversity Data Journal 10, pp. 96467-96467 : 96467

Chilobrachys qishuoi Lin & Li, 2022 sp. n.

Materials

Type status: Holotype. Occurrence: recordedBy: Shuo Qi and Jincheng Liu ; sex: male; occurrenceID: E239F997-4C70-59CD-9731-D57BF718D5CC; Location : country: China; stateProvince: Guangdong; municipality: Qingyuan City ; locality: Qingxin District , X 366 Road , near Jingdong ; verbatimElevation: 313 m; verbatimCoordinates: N24.2320°, E112.8048°; Identification: identifiedBy: Yejie Lin; Event: year: 2022; month: 9; day: 17-22; Record Level: institutionID: IZCAS-Ar 43549 Type status: Paratype. Occurrence: recordedBy: Shuo Qi and Jincheng Liu ; sex: male; occurrenceID: B011EB7C-D71C-58FF-9649-488522763C14; Location : country: China; stateProvince: Guangdong; municipality: Qingyuan City ; locality: Qingxin District , X 366 Road , near Jingdong ; verbatimElevation: 313 m; verbatimCoordinates: N24.2320°, E112.8048°; Identification: identifiedBy: Yejie Lin; Event: year: 2022; month: 9; day: 17-22; Record Level: institutionID: IZCAS-Ar 43550 Type status: Paratype. Occurrence: recordedBy: Shuo Qi and Jincheng Liu ; sex: male; occurrenceID: B011EB7C-D71C-58FF-9649-488522763C14; Location : country: China; stateProvince: Guangdong; municipality: Qingyuan City ; locality: Qingxin District , X 366 Road , near Jingdong ; verbatimElevation: 313 m; verbatimCoordinates: N24.2320°, E112.8048°; Identification: identifiedBy: Yejie Lin; Event: year: 2022; month: 9; day: 17-22; Record Level: institutionID: IZCAS-Ar 43551 Type status: Paratype. Occurrence: recordedBy: Shuo Qi; sex: female; occurrenceID: B011EB7C-D71C-58FF-9649-488522763C14; Location : country: China; stateProvince: Guangdong; municipality: Qingyuan City ; locality: Qingxin District , X 366 Road , near Jingdong ; verbatimElevation: 313 m; verbatimCoordinates: N24.2320°, E112.8048°; Identification: identifiedBy: Yejie Lin; Event: year: 2022; month: 8; day: 20; Record Level: institutionID: IZCAS-Ar 43552 Type status: Paratype. Occurrence: recordedBy: Shuo Qi and Jincheng Liu ; sex: female; occurrenceID: B011EB7C-D71C-58FF-9649-488522763C14; Location : country: China; stateProvince: Guangdong; municipality: Qingyuan City ; locality: Qingxin District , X 366 Road , near Jingdong ; verbatimElevation: 313 m; verbatimCoordinates: N24.2320°, E112.8048°; Identification: identifiedBy: Yejie Lin; Event: year: 2022; month: 9; day: 17-22; Record Level: institutionID: IZCAS-Ar43553

Description

Male (holotype, IZCAS-Ar43549) (Fig. 2 A, Fig. 3 , Fig. 5 , Fig. 6 A, B and Fig. 7 A).

Colouration in alcohol: Carapace, palp and legs red brown. Chelicerae and abdomen black (Fig. 3 A).

Carapace 11.27 long, 9.82 wide, with long white setae. Eye group 2.02 long, 0.91 wide. MOA 1.24 long, anterior width 0.96, posterior width 1.24 (Fig. 3 B). Eye sizes and interdistances: ALE 0.47, AME 0.42, PLE 0.38, PME 0.38; ALE-AME 0.11, AME-AME 0.18, PLE-PME 0.09, PME-PME 0.79. Fovea deep, slightly procurved, on one third of the carapace, occupying about one fifth of carapace width at that point. Four pairs of radial furrows (Fig. 3 A).

Chelicera 6.94 long, 4.80 high, with long white grey setae. Promargin with dense brown hairs, retromargin with one row of 11 teeth, fang furrow with 35 denticles, strikers spiniform. Fang 5.54 long (Fig. 3 G and H).

Labium 1.68 long, 2.21 wide, with 457 cuspules, covering almost 1/3 of area of labium, terminal brown, with long bristles (Fig. 3 D).

Maxilla 4.73 long, 2.18 wide, with 267 cuspules. Stridulating lyra almost two times longer than height, with two kinds of stridulating setae: one row of 10 club-shaped, straight setae and dense spiniform setae (Fig. 3 C, E and F).

Sternum 5.20 long, 4.47 wide, yellow brown, covered with two kinds of hairs: black erect bristles and non-erect brown hairs, separated from labium by fan-shaped areas. Three pairs of sigilla present, anterior pair small, oval; posterior pairs larger (Fig. 3 D).

Legs with dense long and white setae on patellae and tibiae, without any spines. Tarsi I-III with 2 claws, tarsus IV with 3 claws, without denticle. Leg measurements: I 43.11 (12.46 + 4.92+ 11.17 + 8.57 + 5.99), II 37.47 (10.34 + 3.47 + 9.99 + 7.74 + 5.93), III 31.93 (8.07 + 3.28 + 8.09 + 8.12 + 4.37), IV 44.09 (11.57 + 3.45 + 11.55 + 11.92 + 5.60). Leg formula: 4123. Scopula on tarsus IV cracked by a band of macrosetae, scopulae of tarsi I-III not divided.

Abdomen 12.11 long, 6.37 wide, oval, without any pattern, covered with long light brown and white setae of varying lengths. PMS 1.75 long, PLS 8.99 long.

Palp (Fig. 5 , Fig. 6 A, B and Fig. 7 A). Tibia with many setae laterally, swollen at base. Bulb oval, with tegular apophysis; embolus slightly curved, slender, sickle-shaped, with weakly developed apical, prolateral inferior and prolateral superior keels. Distal edge of embolus flat.

Female (one paratype, IZCAS-Ar43552) (Fig. 2 B, Fig. 4 and Fig. 9 d).

Colouration in alcohol: Same as in male (Fig. 4 A).

Carapace 18.75 long, 16.54 wide, with long light brown setae. Eye group 6.41 long, 2.72 wide. MOA 2.19 long, anterior width 2.87, posterior width 4.45 (Fig. 4 B). Eye sizes and interdistances: ALE 1.29, AME 0.98, PLE 1.24, PME 1.05; ALE-AME 0.66, AME-AME 0.71, PLE-PME 0.37, PME-PME 2.90. Others as in male (Fig. 4 A).

Chelicera 10.68 long, 7.93 high, with long light brown setae. Promargin with dense brown hairs, retromargin with one row of 18 teeth, fang furrow with 94 denticles, strikers spiniform. Fang 8.68 long (Fig. 4 G and H).

Labium 2.60 long, 2.98 wide, with 580 cuspules, others as in male (Fig. 4 D).

Maxilla 8.02 long, 4.29 wide, with 580 cuspules. Stridulating lyra almost three times longer than its height, others as in male (Fig. 4 C, E and F).

Sternum 8.48 long, 5.13 wide, others as in male (Fig. 4 D).

Legs with long and short brown setae, others as in male. Leg measurements: I 52.92 (15.19 + 6.58+ 13.56 + 9.37 + 8.22), II 45.25 (13.09 + 5.90 + 11.21 + 8.67 + 6.38), III 40.12 (10.16 + 5.30 + 9.04 + 9.04 + 6.58), IV 51.89 (13.47 + 5.46 + 12.72 + 13.18 + 7.06). Leg formula: 1423.

Abdomen 20.36 long, 12.38 wide, covered with long light brown setae of varying lengths. PMS 2.75 long, PLS 11.87 long.

Spermathecae (Fig. 9 d) simple. Two separated spermathecal lobes, without branch, middle with contraction, swollen distally, straight with genital furrow. Receptacles: 1.62 long, neck width 0.32, base width 0.71; contraction area: 0.46 long; spermathecal lobe: 0.50 long, 0.44 wide. LSE: 1.13 wide, BSE: 0.77 wide. BRV: 56%, LRV: 27%, LBW: 48%, NBW: 35%, NLW: 72%, LSE-BSE 68%.

Diagnosis

The new species is similar in habitus to C. hubei : the male with dense white setae on carapace, patellae and tibiae and the female with light brown carapace and chelicerae (Fig. 2 A and B, Yu et al. 2021, figs. 3A and B). The bulbis similar to those of C. hubei and C. liboensis in having the same angle of the embolus relative to the bulb. The spermathecae are similar to those of C. hubei and C. lubricus by the spermathecal lobes swollen, with contraction at the neck, the base of the receptacles wider than the spermathecal lobes. The ratio of the length of the receptacle to BSE is almost 1:0.5 in C. qishuoi sp. n. and C. hubei and the length ratio of the spermathecal lobe to the contraction area is almost 1:1 in C. qishuoi sp. n. and C. lubricus (Fig. 9 c, d, Yu et al. 2021, figs. 2C-E).

However, the male of C. qishuoi sp. n. can be distinguished from that of C. hubei by the apical keel with an angle range of 60° to 90° (Fig. 7 ) [vs. 120° in C. hubei (Fig. 8 c) and 150° in C. liboensis (Fig. 8 e)], the terminal of the embolus at a right angle in C. qishuoi sp. n. (Fig. 7 ) [vs. blunt in C. hubei and C. liboensis (Fig. 8 c, e)] and the length ratio of the prolateral inferior keel to the apical keel almost 75%-80% in C. qishuoi sp. n. (Fig. 7 ) [vs. 62% in C. hubei (Fig. 8 c) and 42% in C. liboensis (Fig. 8 e)]. In females, the length ratio of the spermathecal lobes to the neck is almost 1:1 in C. qishuoi sp. n. (Fig. 9 d) [vs. 1:0.25 in C. hubei (Fig. 9 b, Yu et al. 2021, fig. 2F)], the receptacles are at 90° angle with genital furrow, with LBW almost 50% and the ratio of the length of the receptacle to the BSE almost 1:0.5 (Fig. 9 d) [vs. 75° angle, LBW more than 50% and the ratio almost 1:0.3 in C. lubricus (Fig. 9 c, Yu et al. 2021, figs. 2D and E)].

Etymology

The species is named after Mr. Shuo Qi, who collected type material; noun (name) in genitive case.

Distribution

Known only from the type locality (China, Guangdong) (Fig. 10 ).

Ecology

The specimens were found in barren limestone rock walls with some vegetation (Fig. 1 B). They construct their retreats in natural rock burrows formed in the karst landscape; the burrows are usually about 6 to 8 cm in diameter. The web extends 20 to 30 cm inwards from the burrow (Fig. 1 A). At night, they move to the entrance of the burrow, waiting for prey to pass by (Fig. 1 C).

DNA barcode

CTATTATTAGATCATCTGTTGGGAAGCGTGAGCCCTTCGGAACTTTGGGAATAATTTATGCTATGGTTAGAATTGGTGGGATGGGGTTTGTTGTATGAGCTCATCATATGTTTTCTGTGGGAATAGATGTAGATACGCGGGCATATTTTACGGCAGCAACTATGGTGATTGCTGTCCCTACGGGAATTAGGGTATTTAGATGAATAGCTACGTTGTATGGATCTTACTTTAAGATGGATACCTCTTTGATATGGTGTGTTGGGTTCGTTTTTTTGTTTACTTTAGGGGGATTAACCGGGGTGGTTTTGGCTAATTCTTCTTTGGATATTATTTTGCATGATACTTATTATGTGGTTGCTCATTTTC (Ar43552, GenBank accession number OP394115).

Figures

Figure 1. Chilobrachys qishuoi sp. n., live. A juveniles in burrow; B habitat in the type locality; C subadult, in situ. Photos by Shuo Qi (A, B) and Yongyou Zhao (C).

Figure 2. Chilobrachys qishuoi sp. n., A holotype male; B paratype female (Ar 43552), live. Photos by Shuo Qi.

Figure 3. Chilobrachys qishuoi sp. n., holotype male A habitus, dorsal; B ocular tubercle; C left maxilla; D sternum; E stridulatory lyra, lateral view; F same, ventral view; G chelicera, retrolateral view; H same, prolateral view.

Figure 4. Chilobrachys qishuoi sp. n., paratype female (Ar 43552) A habitus, dorsal; B ocular tubercle; C left maxilla; D sternum; E stridulatory lyra, lateral view; F same, ventral view; G chelicera, retrolateral view; H same, prolateral view.

Figure 5. Chilobrachys qishuoi sp. n., holotype, male left palp. A prolateral view; B ventral view; C retrolateral view.

Figure 6. Chilobrachys qishuoi sp. n., right palp bulb, rotated horizontally A, C retrolateral view; B prolateral view. Abbreviations: A apical keel; PI prolateral inferior keel; PS prolateral superior keel; TA tegular apophysis.

Figure 7. Chilobrachys qishuoi sp. n., tip of embolus. Abbreviations: A apical keel; EO embolic opening; PI prolateral inferior keel; PS prolateral superior keel.

Figure 10. Distribution records of Chilobrachys species in China: 1 C. dominus; 2 C. guangxiensis; 3 C. hubei; 4 C. jinchengi; 5 C. liboensis; 6 C. lubricus; 7 C. qishuoi sp. n.