Microdytes eliasi Wewalka & Okada, 2023

Okada, Ryohei, Jaitrong, Weeyawat & Wewalka, Guenther, 2023, A review of Microdytes J. Balfour-Browne, 1946 from Thailand, Laos, and Cambodia with descriptions of five new species and new records (Coleoptera, Dytiscidae), ZooKeys 1159, pp. 87-119 : 87

publication ID	https://dx.doi.org/10.3897/zookeys.1159.99218
publication LSID	lsid:zoobank.org:pub:CD97DD12-0549-412F-9765-08D8DE21605B
persistent identifier	https://treatment.plazi.org/id/8C12C23B-3B90-4F46-9D48-F5ABD6625734
taxon LSID	lsid:zoobank.org:act:8C12C23B-3B90-4F46-9D48-F5ABD6625734
treatment provided by	ZooKeys by Pensoft
scientific name	Microdytes eliasi Wewalka & Okada
status	sp. nov.

Treatment

Microdytes eliasi Wewalka & Okada sp. nov.

Figs 2 View Figures 2–6 , 7 View Figures 7–11 , 12 View Figures 12–14 , 42C View Figures 41–43 , 43C View Figures 41–43

Type locality.

Cambodia, Koh Hong Province, 20 km SW Koh Hong, Tatai River, 11°34'N, 103°07'E, alt. 50-300 m.

Type material.

Holotype (NMB): ♂ "Cambodia SW, Tatai riv. 20 km SE Koh Hong 11°34'N, 103°07'E, 3.-19.v.2005, 50-300 m, E. Jendek, O. Šauša leg." [printed white label] \ "HOLOTYPUS Microdytes eliasi sp. nov. Wewalka & Okada 2022" [printed red label]. Paratypes: (47 exs.): 7♂♂, 14♀♀, with same data as the holotype (CGW, CRO, NMB, NMP); 2♂♂, Thailand, Saraburi Province, Kaeng Khoi District, Ched Khot St. 122 (alt. 140 m), 14°28'26"N, 101°09'59"E, 30.V.2020, R. Okada leg. (CRO, THNHM); 4♂♂, 4♀♀, Thailand, Sa Kaeo Province, Mueang Sa Kaeo District, Ban Kaeng St. 277 (alt. 80 m), 13°58'47"N, 102°11'29"E, 30.I.2022, R. Okada leg. (CGW, CRO, THNHM); 2♂♂, 3♀♀, Thailand, Chonburi Province, Bo Thong District, That Thong St. 107 (alt. 100 m), 13°15'01"N, 101°22'34"E, 14.III.2020, R. Okada leg. (CGW, CRO, THNHM); 2♂♂, 2♀♀, same locality St. 298 (alt. 100 m), 13.VII.2022, R. Okada leg. (CGW, CRO); 1♀, same province, Si Racha District, Bang Phra St. 269 (alt. 90 m), 13°14'39"N, 101°02'20"E, 26.XII.2021, R. Okada leg. (CRO); 3♂♂, 2♀♀, Thailand, Chanthaburi Province, Khaeng Hong Maeo District, Kaeng Hong waterfall St. 257 (alt. 160 m), 13°02'57"N, 101°45'35"E, 26.VI.2021, R. Okada leg. (CGW, CRO, THNHM); 1♀, same district, Kha riv. St. 258 (alt. 90 m), 12°57'38"N, 101°46'30"E, 26.VI.2021, R. Okada leg. (CRO). All paratypes are provided with printed red paratype labels.

Diagnosis.

Microdytes eliasi sp. nov. very closely resembles M. maculatus (Motschulsky, 1860) (Figs 25 View Figures 18–37 , 41 View Figures 41–43 ) in size and coloration but differs from this species by the more regularly oval habitus, the laterally expanded median lobe at apex and constricted tips of paramere (Figs 12 View Figures 12–14 , 42C View Figures 41–43 , 43C View Figures 41–43 ) (see also comments in M. maculatus ). It is also similar to M. feryi Wewalka, 2011 (Fig. 21 View Figures 18–37 ) in habitus and coloration, but it is smaller and can be distinguished by male genitalia [compared with a male paratype from Myanmar, "Tenasserim, Birma Coll. V. Helfer National Museum Prague" (CGW)].

Description.

Measurements. TL = 1.64-1.85 mm (1.76 mm), TL-H = 1.49-1.65 mm (1.55 mm), MW = 1.12-1.25 mm (1.24 mm), TL/MW = 1.33-1.44 (1.42). Body regularly oval, moderately convex (Fig. 2 View Figures 2–6 ).

Coloration. Head reddish brown. Pronotum reddish brown, narrowly dark brown along anterior and posterior margins. Elytron dark brown with yellowish brown markings forming a distinct transverse band near base not reaching suture connected along lateral margin with a post-median transverse lateral band, with a small post-median spot near suture, and a triangular spot near apex (Figs 2 View Figures 2–6 , 7 View Figures 7–11 ). Ventral surface of head, prothorax and elytral epipleuron yellowish brown; thorax and abdominal ventrites reddish brown to dark brown. Legs, antennae and palpi yellowish brown.

Sculpture and structure. Head finely, sparsely, and relatively regularly punctured; anterior half to two-thirds finely microreticulate; clypeus not bordered. Pronotum quite regularly, sparsely, and fairly strongly punctured, with coarser punctures along posterior margin; without microreticulation; lateral margins finely bordered, regularly rounded. Elytron quite regularly, moderately densely and fairly strongly punctured, progressively finer and sparser towards lateral margin; without longitudinal rows of stronger punctures; highly polished and shining; without microreticulation. Ventral surface: metacoxae and metasternum strongly but sparsely punctured, abdomen finely and sparsely punctured; without microreticulation.

Male. The two parts of the median lobe expanded laterally at apex in ventral aspect (Figs 12A View Figures 12–14 , 42A View Figures 41–43 ); slightly curved in lateral aspect (Fig. 12B View Figures 12–14 ). The tips of parameres twisted in lateral aspect (Fig. 12C, D View Figures 12–14 ); constricted in ventral aspect (Fig. 43C View Figures 41–43 ).

Female. Without secondary sexual characters. Sclerotized spermatheca not found.

Variation.

Variation of markings is shown in Fig. 7 View Figures 7–11 .

Etymology.

This species is dedicated to Elias Bramböck, Vienna, Austria. The species epithet is a name in the genitive singular.

Habitat.

In Thailand, this species was collected in small streams at low altitude lower than 200 m (Fig. 45 View Figures 45–48 ).

Distribution.

Thailand: Saraburi, Sa Kaeo, Chonburi, and Chanthaburi provinces; Cambodia: Koh Hong Province.