Metadentobunus brevispinus sp. nov.

(Figs. 4-5)

urn:lsid:zoobank.org:act: 0CBDAE16-E48C-4753-A40A- 0E09999E4DEF

Type material: Holotype: 1 S (NCHUZOOL 14599), Sitou, Lugu, Nantou, Taiwan, 23°40'27.92"N, 120°47'45.19"E, elevation of 1107 m, coll. S.-L. Chen, 1 Dec. 2013. Paratypes: 1 $ (NCHUZOOL 14600), 1 S (NCHUZOOL 14586), 1 $ (NCHUZOOL 14587), 1 S (NMNS 7926-001) and 1 $ (NMNS 7926-002), same data as holotype; 1 S (NCHUZOOL 14585), Sun Moon Lake (= Rihyuetan), Yuchih, Nantou, Taiwan, 23°51'26"N, 120°56'42"E, elevation of 764 m, coll. H.-Y. Chang, 19 Jan. 2014; 1 S (NCHUZOOL 14595) and 1 S (NCHUZOOL 14596), Tongfu, Sinyi, Nantou, Taiwan, 23°31'23"N, 120°53'60"E, elevation of 2250 m, coll. S.-L. Chen, 15 July 2015.

Other material examined from Taiwan: 1 $ (NCHUZOOL 14503), Sitou, Lugu, Nantou, 23°40'29.15"N, 120°47'48.55"E, elevation of 1107 m, coll. S.-L. Chen, 1 Dec. 2013; 4 S 3 $ (NCHUZOOL 14504), Tongfu, Sinyi, Nantou, 23°31'23"N, 120°53'60"E, elevation of 2250 m, coll. S.-L. Chen, 15 July 2015; 1 $ (NCHUZOOL 14588), Huisun Forest Area, Ren-ai, Nantou, 24°05'26.55"N, 121°01'58.48"E, elevation of 688 m, coll. S.-L. Chen, 14 Nov. 2014; 1 $ (NCHUZOOL 14589), Furong Waterfall, Guosing, Nantou, 24°05'31.14"N, 120°56'13.95"E, elevation of 636 m, coll. S.-L. Chen, 14 Sep. 2014; 1 S (NCHUZOOL 14590), Aowanda National Forest Recreation Area, Ren-ai, Nantou, 23°56'43.20"N, 121°10'58.01"E, elevation of 1243 m, coll. S.-L. Chen, 1 Oct. 2013; 1 S (NCHUZOOL 14505), Dasyueshan Forest Recreation Area, Heping, Taichung, 24°15'22.32"N, 121°00'24.82"E, elevation of 2240 m, coll. S.-L. Chen, 26 Nov. 2013; 1 $ (NCHUZOOL 14591), Dasyueshan Forest Recreation Area, Heping, Taichung, 24°15'22.32"N, 121°00'24.82"E, elevation of 2240 m, coll. S.-L. Chen, 23 Aug. 2014; 1 S (NCHUZOOL 14592), Cingjing, Ren-ai, Nantou, 24°03'26.19"N, 121°09'47.48"E, elevation of 1891 m, coll. S.-L. Chen, 3 Aug. 2014; 1 $ (NCHUZOOL 14594), Tunyuan, Ren-ai, Nantou, 24°03'1.16"N, 121°12'54.48"E, elevation of 1590 m, coll. S.-L. Chen, 16 June 2015.

Etymology: The name brevispinus is derived from the Latin brevi and spinus, which refers to the one pair frontal spines on ocularium of this species are shorter (Fig. 5 D-E) than the other species of the genus Metadentobunus (Figs. 1 C-D; 3D-E).

Diagnosis: Male: ocularium with one pair of short frontal spines (Fig. 5 D-E). Patella of pedipalp with inner apophysis at tip (Fig. 5 N-O). Shaft long, constricted at base (Fig. 5F). Female: seminal receptacle at 5th-6th segment of ovipositor, with two ampullas terminally (Fig. 5I). Genital operculum flat at frontal margin (Fig. 5P).

Description: Male holotype. Dorsal surface of body granulated. Supra-cheliceral lamellae tipped with 5 small tubercles (Fig. 5L). Abdomen with 1 short median spine on the second tergite. Ocularium rectangle (Fig. 5D), length slightly larger than width, constricted basally, with short spine at frontal margin (Fig. 5E). Frontal spines of ocularium smooth except sparse hairs. All free sternites and genital operculum smooth. Surface of all coxae with scattered coarse granules. Coxa I and IV with a row of humps anteriorly and posteriorly; Coxa II and III with a row of humps anteriorly.

Chelicera (Fig. 5 J-K). Basal segment with 7 tubercles and setae above, with a slender spur ventrally. Distal segment with setae above, outer side smooth, inner side with setae.

Pedipalp (Fig. 5 A-B). All segments with lots of setae, excepting trochanter. Trochanter with 1 conspicuous tubercle. Femur with conspicuous tubercles ventrally, with 11 tubercles on outer side (Fig. 5B) and a row of tubercles on inner side (Fig. 5A). Patella thickened distally, with an inner apophysis at tip. Tibia covered with many simple setae especially in inner tip. Tarsus elongated, with a row of tubercles at inner side (Fig. 5A). Claw pectinate.

© 2018 Academia Sinica, Taiwan

© 2018 Academia Sinica, Taiwan

© 2018 Academia Sinica, Taiwan

Legs. All legs slim and elongate. Trochanters mound-shaped (Fig. 4 A-B), femora II with two false articulations, tarsus longer than tibia.

Penis (Fig. 5 F-G). Shaft 2.28 long, 0.21 wide at base, 0.29 wide at middle; glans 0.2 long, 0.1 wide at base. Shaft long, constricted at base; alate part with sacs (Fig. 5F). Glans widest at base. Stylus acicular.

Female paratypes (NCHUZOOL 14600, NMNS 7926-002): Dorsal surface of body similar to male, excepting abdomen of female longer than male (Fig. 4 C-D). Frontal spines of ocularium smooth except sparse hairs. Supra-cheliceral lamellae tipped with 2-4 small tubercles (Fig. 5M). Trochanter of pedipalps with 1 conspicuous tubercle ventrally. Pedipalpal femur with a row of black-tipped tubercles at inner side, tibia covered with simple setae entirely (Fig. 5C). Inner-tip apophysis of pedipalpal patella longer than male. Pedipalpal tibia of female with small apophysis at inner tip (Fig. 5O). Genital operculum flat at frontal margin (Fig. 5P). Seminal receptacle (Fig. 5I) located in 5th-6th segment of ovipositor, terminal with two ampullas.

Measurements: Holotype male (female paratype, NCHUZOOL 14600): Cephalothorax 1.15 (1.68) long, 2.62 (3.0) wide; abdomen 2.16 (3.78) long, 2.41 (3.39) wide. Total length of body 3.31 (5.46). Measurements of left pedipalp and legs are shown in table 3. Female: similar with male, but darker than male.

Coloration: Male. Dorsum golden yellow with granules, spine on second tergite black (Fig. 4 A- B). Carapace golden yellow with small light brown flecks along frontal and lateral edge. Ocularium golden yellow, with white eye rings. Coxa of all legs golden yellow. Genital operculum golden yellow, light yellow base, distal edge light yellow. Sternites pale yellow, whiten posterior. Chelicerae pale yellow, basal segment with brown spots. Pedipalps pale yellow, with femora and patellae brown. All legs brown with golden yellow rings. Female similar with male, but darker (Fig. 4 C-D).

Variation: One female specimen (NCHUZOOL 14588) has frontal spines with finely granulated tip on ocularium. In addition, the female specimen (NCHUZOOL 14591) from the Dasyueshan Forest Recreation Area has slender and long penile shaft and the different morphology of penile alate part (Fig. 5H).

Distribution: Central Taiwan (Fig. 7).

Habitat: This species can be found on the tree trunks, sometimes on the artificial wooden guideboard.

Remarks: This new species can be separated from other congeneric species by having one pair of shorter (than other congeners) spines at frontal margin of the ocularium (Fig. 5 D-E, Q). It can be also distinguished from M. garampiensis by the number of tubercles on the dorsal basal segment of the chelicera (7 vs. 14-15) (Fig. 5 J-K vs. Fig. 3 J- K), the basal shape of the penile shaft (constricted vs. parallel) (Fig. 5F vs. Fig. 3G), location of the seminal receptacle in ovipositor (5th-6th segment vs. 6th-7th segment) and number of ampullas in the terminal of seminal receptacle (2 vs. 3) (Fig. 5I vs. Fig. 3L).

DNA analyses

A 451 base-pair (bp) segment of 16S and 624 bp segment of COI from 19 specimens of the genus Metadentobunus and outgroups were amplified and aligned (Table 1). No specimen of M. formosae was collected and therefore the species was not be included in the molecular analysis. The phylogenetic tree of the combined genes was constructed by BI (Fig. 6), and the bootstrap support values from ML analysis was also shown on the tree. It is clear that the genus Metadentobunus is monophyletic with high support by both BI and ML methods. There are two clades within Metadentobunus with high BI support, and they are referred to as M. garampiensis and M. brevispinus sp. nov., respectively.

© 2018 Academia Sinica, Taiwan

With regard to genetic divergence, the maximum intraspecific and the minimum interspecific COI distances of Metadentobunus are 2.63-5.03% and 6.79%, respectively (Table 4).