Quedius masuzoi Watanabe, 1989

Hu, Fang-Shuo, Bogri, Amalia, Solodovnikov, Alexey & Hansen, Aslak Kappel, 2020, Hypogean Quedius of Taiwan and their biogeographic significance (Coleoptera: Staphylinidae: Staphylininae), European Journal of Taxonomy 664 (664), pp. 1-24 : 5-17

Quedius masuzoi Watanabe, 1989

Figs 2 , 3 A–B, D–E, G–H, 4 A, 9 B (adult); 5 – 8 , 9 C (larva)

Quedius masuzoi Watanabe, 1989: 170 , figs 1–4 (description; type locality: Taiwan, Nan-t’ou Hsien, Mt Neng-kao-pei-feng [= 能 高北 峰 = 南華山 = Nanhua Mt], alt. 2870 m).

Quedius chiangi Smetana, 1995: 48 , fig. 54 (description). Syn. nov.

Quedius masuzoi – Smetana 1995: 45, figs 49–53 (redescription).

Diagnosis (adult)

Quedius masuzoi ( Fig. 4A ) is very similar to the two other species of the abnormalis group in Taiwan. From Q. nishikawai it can be distinguished by the shorter antenna and sclerotization pattern of tergite X, which has a distinctly heavier sclerotized stalk connecting its more sclerotized apical and basal areas (compare Figs 3G, H and 4I ). From Q. adilus sp. nov. it can be distinguished by the shorter and wider median lobe of the aedeagus, which is only slightly protruding over the apical margin of the bilobed paramere (in parameral view) (compare Fig. 3 A–B and 3C).

Diagnosis (larva)

Head capsule parallel-sided, not narrowing anteriad towards bases of mandibles, with four weakly visible white stemmata on each side, without dark pigment spots inside them; frayed setae present from metathorax to apex of abdomen; apotome with short stalk not extending beyond tentorial pits ( Fig. 6B ); inner margin of mandible without small tooth ( Fig. 6A, E ); maxillary and labial palp 3- and 2-segmented, respectively, last segment of maxillary palp longer than penultimate segment, weakly divided into two pseudosegments ( Fig. 6E ); protibial comb with irregular row of 8–10 split (bifid) spines ( Fig. 7C ).

Material examined (all adults unless indicated as larvae)

Holotype (of Quedius chiangi )

TAIWAN • ♀; Nantou Hsien, Yushan Natonal Park, Pai-Yun Hut [玉山 排 雲山莊]; alt. 3528 m; 15 May 1991; “ A. Smetana [T83] / HOLOTYPE ”; “ Quedius chiangi A. Smetana 1993 [red label, hand writing]”; NMNS.

Other material

TAIWAN • 1 ♂, 1 ♀; Chiayi Co., Shi Mt race [石山引 水道], Alishan To ; 23.4691° N, 120.8583° E; alt. 2360 m; 11 Feb. 2019; Y.T. Lai leg.; subterranean water diversion construction; NHMD • 1 ♂; same collection data as for preceding; 23 Feb. 2019; F.S. Hu leg.; FSHc • 1 ♂; same collection data as for preceding; DNA voucher specimen FS001 (GenBank: MN989304 ); NMNS • 1 ♀; same collection data as for preceding; 11 Feb. 2019; Y.T. Lai leg.; DNA voucher specimen FS002 (GenBank: MN989305 ); FSHc • 1 ♀; same collection data as for preceding; 3 Feb. 2019; Y.T. Lai leg.; DNA voucher specimen FS003 (GenBank: MN989306 ); FSHc • 1 ♀; same collection data as for preceding; 23 Feb. 2019; B.H. Ho leg.; DNA voucher specimen FS004 (GenBank: MN989307 ); NMNS • 1 ♂; same collection data as for preceding; F.S. Hu leg.; DNA voucher specimen FS005; NMNS • 1 ♂; same collection data as for preceding; 24 Feb. 2019; F.S. Hu leg.; DNA voucher specimen FS006; NMNS • 1 ♀; same collection data as for preceding; DNA voucher specimen FS007; NMNS • 1 ♂; same collection data as for preceding; 21 Feb. 2020; W.Z. Tseng and H.Y. Lin leg; FSHc • 2 larvae; same collection data as for preceding; 23 Feb. 2019; F.S. Hu leg.; DNA voucher specimens FS008L (GenBank: MN989308 ), FS009L [2 specimens in different vials]; FSHc • 2 larvae; same collection data as for preceding; DNA voucher specimens FS010L (GenBank: MN989309 ), FS011L [2 specimens in different vials]; NHMD .

Description (adult)

Male

See Watanabe (1989) and Smetana (1995).

Female

See original description of Q. chiangi in Smetana (1995) .

Character variability and new synonymy

Smetana (1995) described Q. chiangi as a species very similar to Q. masuzoi , but differing from the latter in the position of the posterior frontal puncture and the number of its additional setiferous punctures. Smetana (1995) expressed the position of the frontal puncture as a ratio of the distances between that and the hind margin of the head to the distance between the frontal puncture and the hind margin of the eye. According to this, the posterior frontal puncture is positioned at a ratio of no more than 1.5 in Q. masuzoi , whereas in Q. chiangi this ratio is roughly 3.5, which in effect means that this puncture in Q. chiangi is positioned much closer to the hind margin of the eye. Furthermore, Smetana (1995) mentioned one additional setiferous puncture posteriad of the posterior frontal puncture in Q. masuzoi and two to three punctures postero-mediad of the posterior frontal puncture in Q. chiangi .

Our new material with the sequenced CO1 barcode, however, shows that the mentioned traits are quite variable even within our sample of specimens from the same locality with identical barcodes. We found that the position of the posterior frontal puncture, expressed in the same ratio as Smetana (1995), varies in our sample between 1.46 and 4.90, meaning that the intraspecific variability range encompasses the differences reported as interspecific by Smetana (1995). One of our specimens was completely missing the posterior frontal puncture on one side. Remarkably, the position and number of additional setiferous punctures near the posterior pronotal puncture also vary in our specimens, ranging from missing through having one anterio-mediad to having multiple posterio-mediad.

We also found additional overlap in other ratio values and characters mentioned as differences between the two species by Smetana (1995). Specifically, the head width to length ratio varies in our conspecific material from 1.14 to 1.36 ( Q. masuzoi 1.14 and Q. chiangi 1.10 in Smetana 1995). The ratio of length of temples to length of eyes varies from 4.27 to 7.33 ( Q. masuzoi 4.73 and Q. chiangi 4.58 in Smetana 1995). The ratio of length to width of antennomere 4 varies from 0.75 to 1.6 ( Q. masuzoi 1.09 and Q. chiangi > 1.09 in Smetana 1995). The scutellum varies in the degree of punctation, with one specimen having it totally glabrous.

Noteworthy is that the female tergite X of Q. chiangi illustrated in Smetana (1995) has the same sclerotization pattern as in all females of Q. masuzoi that we examined, namely a heavier sclerotized apical area with a similar darker stalk connecting this area with the base of the tergite ( Fig. 3 G–H). Also, the geographic proximity of the type locality of Q. chiangi to the locality where additional material of Q. masuzoi was collected ( Fig. 2 ) is noteworthy.

Examination of the holotype of Q. chiangi confirmed our thoughts, with all characters fitting within the explained variability, except for its size being slightly smaller. Based on all these considerations, we place Q. chiangi in synonymy with Q. masuzoi .

Description (larva)

The larva of Q. masuzoi ( Fig. 5 ) possesses all the characters of the subfamily Staphylininae : toothed nasale ( Fig. 6A ); non-setose ligula ( Fig. 6E ); eyes of four stemmata each ( Fig. 6C ); anterior position of sensory appendage on antennal segment III ( Fig. 6D ); triangular cervicosternum with its apex projecting between proepisterna ( Fig. 7B ); and tarsungulus with three spines ( Fig. 7C ). It has 2-segmented labial palps and 3-segmented maxillary palps ( Fig. 6E ), relatively short urogomphi (about as long as pygopod) ( Fig. 9C ), frayed setae on the body ( Figs 7A , 8 ) and combs of split (bifid) spines on anterior tibia ( Fig. 7C ), as in other Quediini . Overall, it fits the larval diagnosis of the genus Quedius given in Pietrykowska-Tudruj et al. (2014), which, however, was based on limited material. Based on the data in Pietrykowska-Tudruj et al. (2014) and our experience with larvae of other Staphylininae , we have above provided a diagnosis which should facilitate the separation of larvae of Q. masuzoi and related hypogean species from those of other Quedius or Quediini , supplemented by the following description.

GENERAL. Body length 10–11 mm; head length 1.9–2.1 mm, width 1.5–1.6 mm; pronotum length 1.8– 1.9 mm, width 1.5–1.7 mm. Body slender, with relatively large head and long legs, prothorax as wide as parallel-sided head, meso- and metathorax, as well as basal four segments of abdomen; from segment IV abdomen gradually narrowing posteriad. Habitus as in Fig. 5 , head capsule brownish, protergum, thorax and legs pale brown, abdomen whitish-grey, setae brown to dark brown. All macro- and microsetae of head, pro- and mesothorax and some setae on abdominal segments simple; few macrosetae on metathorax, the majority of those on abdomen, except pygopod, apically frayed ( Figs 6–8 ).

HEAD. With broad but distinct neck, slightly longer than wide ( Fig. 6 A–B). Chaetotaxy of dorsal side of head as in Fig. 6A , as a pattern of larger and smaller simple setae, with distinct pair of epicranial glands (Gl), and poorly visible small olfactory organs (Og) and sensilla (Sm) on nasale. Four pale stemmata (Ast) without pigment spots, in cluster on each side ( Fig. 6C ). Ventral side of head with chaetotaxy as in Fig 6B , with clearly visible tentorial pits (Tp) extended along short stalk of apotome (Apt). Antenna ( Fig. 6D ) 4-segmented, slender, segment III longer than segment II; segment II with one large ‘pore’ dorso-laterally; segment III with three macrosetae, large apically pointed sensory appendage (SA) and one ‘pore’ (ventrolateral); segment IV with three subapical macrosetae and a group of small setae and four solenidia apically. Nasale (Na) with nine teeth at apical margin, with pair of paramedian teeth being the longest. Mandibles ( Fig. 6A ) slender, apically very sharp, with one large seta externally at base. Stipes of maxilla ( Fig. 6E ) with several macrosetae, two of them distinctly larger than others. Mala (Ma) finger-like, ca three times as long as wide at base ( Fig. 6E ). Palpifer (Pf) with one seta ventrally. Maxillary palp 3-segmented, its apical segment the longest, weakly subdivided into two pseudosegments. Labium ( Fig. 6E ) with well-sclerotized ventral side of prementum (Pmn), with four setae apically. Ligula (Lg) conical, ca two times as long as wide. Labial palps 2-segmented; segment II distinctly thinner and longer than I.

THORAX. Prothorax as long as wide, meso- and metathorax wider than long, of similar structure, metathorax slightly shorter than mesothorax; protergite with posterior carina, meso- and metatergite with anterior and posterior carinae ( Fig. 7A ). Pronotum and mesonotum with simple (not frayed) setae only; metanotum with larger setae frayed, smaller setae simple. Pro-, meso- and metanotum with smooth, glossy cuticle. Cervicosternum (CR) large, triangular, with pair of setae medially. Sternites of prosternal area (Sn) each with one seta ( Fig. 7B ).

LEGS. Relatively long, all of about the same length; femora with strong, long spines ventrally, tibia with similar spines dorsally and ventrally; tibial comb (Cb) present on anterior legs only, consists of up to ten split (bifid) spines; rather long, apically very sharp tarsungulus (Tu) with three spines ( Fig. 7C ).

ABDOMEN. Ten-segmented; only segment I with visible brownish glossy tergite and with distinct anterior carina; other segments without visible darker sclerites, whitish-grey. All abdominal segments with frayed setae, large and small, and with some simple small setae. Tergal chaetotaxy of segment I ( Fig. 7A ) simpler than on segments II–VIII (e.g., Fig. 8A of segment III), the latter having the same serially homologous pattern. Segment IX with reduced chaetotaxy ( Fig. 8B ), without laterosclerites and ecdysial line. Segment X (pygopod) with dense, long simple setae ventrally and short frayed setae dorsally, slightly longer than short urogomphi (measured without apical seta), the latter with few simple, frayed macrosetae, each with one long, frayed apical macroseta ( Fig. 8C ).

Note

The lack of notable pigmentation of the stemmata and the relatively long legs are apparently adaptations to the hypogean environment during the larval stage.

Molecular results and identity of the new material

We sequenced the CO1 barcode for six specimens (four adults and two larvae) of the putative Q. masuzoi from the same locality, a subterranean water diversion channel at Mt Shi ( Fig. 9 ). All larvae and adults showed matching CO1 barcodes, supporting the idea that they are conspecific. There were no ambiguous sites within the six barcoded individuals, and thus the dissimilarity between them equals 0.000 ( Fig. 10 ). The two species, Q. mesomelinus and Q. scitus , used as outgroup, showed a 0.131 dissimilarity to our samples of Q. masuzoi and a dissimilarity of 0.115 between each other. They also showed larger within species dissimilarity compared to Q. masuzoi (0.007 in Q. mesomelinus and 0.002 in Q. scitus ). The larger within species dissimilarity in the outgroup species is probably due to the larger geographic range of the sampled specimens. All our putative Q. masuzoi samples were from the same site and collecting event, whereas samples for the outgroup species from GenBank come from multiple localities which are geographically remote from one another. Aedeagi were identical in all five males in the sample of our newly collected material and fully match the illustrations of the aedeagus of Q. masuzoi in Watanabe (1989) and Smetana (1995), reliably identifying our specimens as that species ( Fig. 3 A–B, D–E).

Distribution

This species is known from three localities: from Mt Neng-kao-pei-feng in northeastern Taiwan (type locality of Q. masuzoi ), as well as from Pai-Yun Hut, Yushan National Park (type locality of Q. chiangi ) and nearby Mt Shi (newly collected material) in the central part of the island (i.e., from Nantou and Chiayi Counties) ( Fig. 2 ).

Bionomics

The holotype of Q. masuzoi was dug out from loose rocks with poor vegetation ( Watanabe 1989). For Q. chiangi , the holotype was collected from an old rocky wall, while the collecting circumstances of the paratype remain unknown ( Smetana 1995). The additional specimens of Q. masuzoi reported here were collected from a short subterranean tunnel ( Fig. 9A ) close to the type locality of Q. chiangi . The rocky walls of the tunnel were covered by bat guano and its entrance opens to a primary forest. Adults were observed both on the surface of the ground and under the rocks of the tunnel ( Fig. 9B ). Larvae ( Fig. 9C ) were collected under rocks in the same tunnel, during the same collecting event. Leiodidae spp, other rove beetles belonging to Xantholinini (all Coleoptera ), Rhaphidophoridae sp. ( Orthoptera ) and Nycteribiidae sp. ( Diptera ) were found in the same tunnel. The collected adults and larvae of Q. masuzoi were kept in the laboratory for over two weeks, where they were fed with both live and dead Rhaphidophoridae sp., Blatta lateralis Walker, 1868 (Blattodea) and Odontotermes formosanus (Shiraki, 1909) (Blattodea) . Despite being supplied with live prey, both adults and larvae fed on dead prey only, i.e. they did not display predatory behaviour in the laboratory. Unfortunately, we did not rear any adults from the collected larvae and no other significant observations on their behaviour were made.

Remarks

The holotype of Q. chiangi is in good condition, mounted on a card. Segment 3–4 of the left maxillary palpus, antennomeres 4–11 of left antenna, the left fore claw, and the left hind tibia and femur are missing. The genital segment was dissected and sealed using Euparal, placed on a plastic card pinned underneath the paper card.

Figures

Fig. 2. Distribution of species in the Quedius abnormalis group in Taiwan. Filled square - refers to the new specimens of adults and larvae of Quedius masuzoi Watanabe, 1989 reported in this paper. Square with cross Oi is the type locality of Quedius masuzoi. Unfilled square D is the type locality of Quedius chiangi Smetana, 1995, junior synonym of Q. masuzoi. Question mark (?) refers to an undescribed female specimen reported in Watanabe (1989). Unfilled circle O is the type locality of Quedius nishikawai Watanabe, 1991. Filled star * is the type locality of Quedius adilus sp. nov.

Fig. 3. Aedeagi and female terminalia of species of the Quedius abnormalis group from Taiwan. The graphic symbol on each illustration refers to the collection locality on Fig. 2 as follows: filled square - to the new specimens of Quedius masuzoi Watanabe, 1989 reported in this paper; square with cross Oi to the male holotype of Quedius masuzoi; unfilled square D to the female holotype of Quedius chiangi Smetana, 1995, synonym of Q. masuzoi; unfilled circle O to the female holotype of Quedius nishikawai Watanabe, 1991; filled star * to the male holotype of Quedius adilus sp. nov. Top row (A–C): parameral view of aedeagus. Middle row (D–F): lateral view of aedeagus. Bottom row (G–I): female tergite X. Scale bars = 0.5 mm.

Fig. 4. Habitus images of holotypes. A. Quedius masuzoi Watanabe, 1989. B. Quedius nishikawai Watanabe, 1991. Scale bar = 1 mm.

Fig. 9. Photographs of collection site and live specimens of Quedius masuzoi Watanabe, 1989. A. Habitat of newly collected specimens reported in this paper. B. Adult. C. Larva.

Fig. 5. Quedius masuzoi Watanabe, 1989. Photographs of larvae. A. Ventral view. B. Dorsal view. C. Lateral view. Scale bar = 1 mm.

Fig. 8. Quedius masuzoi Watanabe, 1989. Morphology of larva: abdomen. A. Abdominal segment III, dorsal view. B. Apex of abdomen, dorsal view. C. Apex of abdomen, lateral view. Abbreviations: Abd III = abdominal segment III; Spi = spiracle. Scale bars = 0.5 mm.

Fig. 6. Quedius masuzoi Watanabe, 1989. Morphology of larva: head. A. Head capsule, dorsal view. B. Head capsule, ventral view. C. Head capsule, lateral view. D. Antenna, dorsal view. E. Maxilla and labium, ventral view. Abbreviations: Apt = apotome; Ast = stemmata; Cd = cardo; Des = dorsal ecdysial line; Ed = epicranial dorsal seta; El = epicranial lateral seta; Em = epicranial marginal seta; Ep = epicranial part; Gl = epicranial gland; L = lateral seta; Lg = ligula; Ma = mala; Na = nasale; Og = olfactory organ; p = posterior seta; Pa = posterior area; Pf = palpifer; Pmn = prementum; Sa = sensory appendage; Sm = sensilla; St = stipes; Tp = tentorial pit; V = ventral seta; Ves = ventral ecdysial line; Vl = ventral lateral seta; Vm = ventral medial seta; I–IV = segment enumeration. Scale bars = 0.5 mm.

Fig. 7. Quedius masuzoi Watanabe, 1989. Morphology of larva: thorax and base of abdomen. A. Body fragment (thorax and abdominal segment I), dorsal view. B. Prothorax, ventral view. C. Anterior leg from anterior side. Abbreviations: Abd I = abdominal segment I; Cb = comb; CR = cervicosternum; Fe = femur; Meso = mesonotum; Meta = metanotum; Pro = pronotum; Sn = sternite of prosternal area; Tb = tibia; Tu = tarsungulus. Scale bars = 0.5 mm.

Fig. 10. Maximum likelihood species tree of CO1 barcodes. The sequences of Quedius masuzoi Watanabe, 1989 were produced in this study. Sequences of Quedius scitus (Gravenhorst, 1806) and Quedius mesomelinus (Marsham, 1802) are from GenBank. Numbers represent within (on branch) and between (at node) species dissimilarity of CO1 barcodes.