Zaitzevia yingzuijieensis Jiang & Chen, 2023

Jiang, Ri-Xin & Chen, Xiang-Sheng, 2023, Three new species of the genus Zaitzevia Champion, 1923 (Coleoptera, Elmidae) from China, ZooKeys 1174, pp. 191-206 : 191

Zaitzevia yingzuijieensis Jiang & Chen sp. nov.

Figs 1C , 6 , 7 鹰嘴界寥溪泥甲

Type material

(7 ♂, 1 ♀). Holotype: China: ♂, labeled 'China: Hunan, Huaihua City (怀化市), Huitong County (会同县), Yingzuijie N. R. (鹰嘴界国家级自然保护区), light trap, H: ~400m, 02.08.2022, J.-H. Huang leg.' (GUGC). Paratype: 6 ♂♂, 1 ♀, with the same label data as the holotype (GUGC).

Description.

Male. Body elongately elliptical (Fig. 1C ), dark brown or brown, legs brown, antennae and apical margin of labrum and pronotum reddish brown. Dorsal surface punctuated and shiny, covered with sparse setae. Plastron setae is confined to following areas: head (both dorsal and ventral surface, except clypeus), prosternum, outer part of elytra (include epipleura), outer parts of mesoventrite, metaventrite and abdomen (except median part) and surface of femora.

Head (Fig. 6A ), wider than long, surface covered with plastron setae and large, sparse punctures, each puncture bearing a longer seta, the interspaces between the punctures about twice the diameters of punctures. Clypeus evenly punctate with large punctures and covered with long, sparse setae, without plastron setae. Labrum transverse, about as wide as clypeus, covered with big punctures and long bristles at apical 2/3 portion, anterior margin finely rounded, anterolateral angles rounded. Antenna short, with eight antennomeres, antennomere I slightly longer than wide, with several short setae; antennomere II slightly longer than antennomere I, strongly expanded, covered with several long setae, apical margin circled with short setae; antennomere III longer than wide; antennomeres IV-VII strongly transverse; antennomere VIII elliptical, elongate and strongly expanded, apex covered with dense long setae.

Pronotum (Fig. 6B ) slightly wider than long, widest at base. Anterior margin arcuate with angles moderately produced and acute. Lateral margins finely curved. Basal margin trisinuate, emarginate before scutellum, posterior angles obtuse. Surface shiny, finely covered with large punctures, each puncture bearing a long seta; surface near apical angles microreticulate, setae on anterior half longer than on other parts. Longitudinal impression distinct but short, less than 1/3 length of pronotum, widest at basal 1/3; sublateral carinae short and shallow, from base to 1/3 of pronotum, near straight; a pair of small foveae located at middle of base of pronotum. Prosternal process (Fig. 6D ) with rounded apex, disc shiny without punctures or setae, sides microreticulated.

Elytra (Fig. 6C ) about 1.70 times as long as wide, subparallel in basal 1/3, surface shiny and covered with rows of long, sparse setae. Each elytron with granulate carinae on strial intervals 5, 7, and 8; other intervals flat. Area from intervals to lateral margin covered with dense short setae. Hind wings well developed.

Metaventrite (Fig. 6E ), disc shiny, covered with large, sparse punctures, each bearing a long seta, without plastron setae, sides covered with plastron setae. Median sulcus long and distinct, extending from posterior margin to ca. 4/5 of metasternum, widest at base and get narrowed to apex, base of median sulcus with a pair of small round impressions. Areas along coxal cavities with a series of shallow and anomalous impressions.

Disc of ventrites I-IV and anteriorly middle of ventrite V shiny, covered with sparse small punctures, without plastron setae, other areas of ventrites covered with plastron setae. Apical area of ventrite V granulated, apical margin distinctly emarginate at middle.

Legs simple, femora swollen, surface covered with plastron setae; inner half of tibiae with cleaning fringes; tarsi about as long as tibiae; tarsal claws simple.

Aedeagus (Fig. 7A-D ), slender and elongate, median lobe nearly symmetrical, apex of median lobe cuspidal and distinctly asymmetrical, a pair of symmetrical and elongate sclerotizations located at apical 1/4 of median lobe, a pair of shorter and symmetrical sclerotizations located at basal 1/3 of median lobe. Sternite IX (Fig. 7E ) with apical margin finely rounded, with a tuft of long setae, paraproct with basal round and expanded.

Measurements: CL: 2.33-2.38 mm; HL: 0.28-0.30 mm, HW: 0.40-0.41 mm; PL: 0.56-0.58 mm, PW: 0.74-0.76 mm; EL: 1.77-1.80 mm, EW: 0.91-0.93 mm.

Female: externally similar to the male, apex of sternite V rounded. Ovipositor as in Fig. 7F-H , stylus curved at base, apex with three short, finger-like sensilla; apex of coxite weakly roundly broadened at outer margin, with a curving sensilla; valvifer about 1.5 times as long as coxite, fibula distinctly curved at basal 1/2, base weakly expanded. Measurements: CL: 2.48 mm; HL: 0.33 mm, HW: 0.45 mm; PL: 0.65 mm, PW: 0.79 mm; EL: 1.83 mm, EW:0.96 mm.

Distribution.

China: Southwest Hunan Province.

Biology.

All adults were collected by light trap. They might have similar habitat with other Zaitzevia species.

Etymology.

The specific epithet refers to the type locality, Yingzuijie Nature Reserve, Hunan Province; the name is treated as an adjective.

Comparative diagnosis.

The new species shares a similar habitus with several other species including the following: Zaitzevia yaeyamana Satô, 1963 from Japan, and Z. tangliangi Jiang & Wang, 2021. All species have a small body size (<3mm) and a very short, longitudinal impression on the pronotum. Z. yingzuijieensis sp. nov. can be distinguished from Z. yaeyamana by the following characters: 1) punctures on elytra much denser (vs sparser in Z. yaeyamana ); 2) punctures on elytra much large (vs punctures on elytra very thin in Z. yaeyamana ); 3) median lobe of aedeagus long and slender, about three times as long as phallobase (vs median lobe of aedeagus much stronger and shorter, about twice as long as phallobase in Z. yaeyamana ). Zaitzevia yingzuijieensis sp. nov. can be distinguished from Z. tangliangi by the distinctly asymmetric apex of the median lobe of the aedeagus, while the apex of the median lobe is nearly symmetrical in Z. tangliangi . The sclerotizations near the apex of the median lobe is rounded at one end in the new species but pointed in Z. tangliangi .

Figures

Figure 1. Dorsal habitus of Zaitzevia species, males A Zaitzevia sichuanensis sp. nov. B Zaitzevia fengtongzhaiensis sp. nov. C Zaitzevia yingzuijieensis sp. nov. Scale bar: 1 mm.

Figure 6. Diagnostic features of Zaitzevia yingzuijieensis sp. nov. A head, dorsal view B pronotum, dorsal view C elytra D prosternal process E metaventrite. Scale bars: 1 mm (C); 0.25 mm (A, B, D, E). Note: red arrow of C granulate carinae of elytra; red arrow of E impressions and median sulcus of metaventrite.

Figure 7. Diagnostic features of Zaitzevia yingzuijieensis sp. nov. A aedeagus, dorsal view B ditto, lateral view C ditto, ventral view D ditto, meidan lobe, dorsal view E sternite IX F ovipositor G, H apical part of ovipositor. Scale bars: 0.5 mm (A-C, E, F); 0.2 mm (D, G); 0.1 mm (H).