Quedius nishikawai Watanabe, 1991

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 : 17

Quedius nishikawai Watanabe, 1991

Figs 2 , 3I , 4B

Quedius nishikawai Watanabe, 1991: 225 , fig. 6 (description; type locality: S Taiwan, Mt Pei-ta-wu Shan [北 大 武山], alt. 2520 m, Tai-wu Hsiang, P’ing-tung Hsien).

Quedius nishikawai – Smetana 1995: 48, fig. 55 (redescription).

Diagnosis

Quedius nishikawai is quite similar with Q. masuzoi ( Fig. 4 ) but, according to Watanabe (1991) and Smetana (1995), it can be distinguished from the latter at least by the larger and more robust body, with broader head and elytra, the longer antennae with notably longer antennomeres 8–10 and by the presence of minute punctation on the head. Based on the newly discovered females for Q. masuzoi , we can add that the female of Q. nishikawai differs from that of the former species by its tergite X, which does not have the distinct stalk connecting the other heavier sclerotized apical and basal areas of the tergite (compare Fig. 3I and 3 G–H).

Description

Male

Unknown.

Female

See Watanabe (1991) and Smetana (1995).

Distribution

Known only from the type locality in Pingtung County, S Taiwan ( Fig. 2 ).

Bionomics

Nothing is known about the bionomics of this species, except that it was collected at a high elevation, similarly to other members of the abnormalis group in Taiwan.

Remarks

Quedius nishikawai remains known only from the single female ( Fig. 4B ) that the original description ( Watanabe 1991) and later redescription ( Smetana 1995) were based on. As can be seen from the case of Q. masuzoi above, the external characters used for species delimitation in this group turned out to be quite variable, even among clearly conspecific specimens from the same locality. Also, based on the case of Q. masuzoi and some other non-Taiwanese hypogean species studied in Solodovnikov & Hansen (2016) and Salnitska & Solodovnikov (2018), we can see that the distributions of hypogean species may not be that locally restrained, contrary to common assumptions made by systematists about very low dispersal abilities in such species and high levels of local endemism. Therefore, in view of the data presented in this paper, the status of Q. nishikawai as a separate species remains unclear until males are found. Given at least a distinct difference between Q. nishikawai and Q. masuzoi in the sclerotization pattern of the female tergite X ( Fig. 3 ), the species status of for the former is justified at the moment.

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.