Agraphydrus komareki Yang & Jia, 2021

Yang, Zhen-ming, Jia, Fenglong, Jiang, Lu & Guo, Qiang, 2021, Four new species of Agraphydrus Regimbart, 1903 with additional faunastic record from China (Coleoptera, Hydrophilidae, Acidocerinae), Deutsche Entomologische Zeitschrift 68 (1), pp. 189-205 : 189

Agraphydrus komareki Yang & Jia sp. nov. Figs 1C, D ; 4 ; 7B

Type locality.

China, Guangdong Province, Taishan County, Shangchuan Island.

Material examined.

Holotype: male (SYSU), Guangdong Province , Taishan, shangchuan island, Rhesus monkey provincial national nature reserve, ca 21°46'12"N, 112°51'39"E, 10m a.s.l., 19.I.2019, Fenglong Jia & Zu-long Liang leg. Paratypes (13 exs., IZCAS, SYSU): same data as holotype .

Diagnosis.

This species is distinguished from the other species of Agraphydrus by the following combination of characters: Labrum, clypeus and frons black; preocular patches present; clypeus entirely microsculptured; maxillary palpi with apical palpomere about 1.5-1.6 × as long as penultimate, palpomere 4 without apical infuscation; antennae with eight antennomeres; elytra with four systematic punctures; meso- and metafemora pubescent in about basal 3/4; aedeagus with median lobe wider than parameres, corona large, located at basal third; parameres with indistinct subapical constriction. Differs from A. gracilipalpis by eight antennomeres and features of the aedeagus.

Description.

Form and color. Total length: 1.6-2.0mm; elytral width: 0.8-1.0mm; E.I.:1.1-1.3, P.I.:2.1-2.4, elytra 2.6-3.0 × as long as pronotum. Body oval, convex dorsally. Labrum, clypeus and frons dark reddish-brown, clypeus with reddish-brown preocular patches; maxillary palpi unicolored yellow; pronotum dark reddish-brown mesally with light red brown margin; elytral dark reddish-brown, lighter posteriorly; ventrites reddish-brown or brown; legs light brown or light reddish-brown.

Head. Labrum entirely microsculptured, with few punctures at the anterior margin. Clypeus (Fig. 4A ) with angularly excised anterior margin, entirely microsculptured, ground punctures sparse, interspaces 3-4 × as large as punctures, systematic punctures distinct. Frons with dense ground punctures, interspaces 2-4 × as large as punctures, systematic punctures distinct. Eyes large, not protruding. Antennae (Fig. 4B ) with eight antennomeres. Maxillary palpi (Fig. 4C ) 1.2-1.3 × as long as pronotum in midline, about as long as maximum width of clypeus; length ratio palpomere 4:3 =1.5-1.6, palpomere 4 asymmetrical. Mentum (Fig. 4D ) with sparse coarse punctures, microsculpture existing on lateral portions.

Thorax. Pronotum ca. 1.1-1.3 × as wide as long, pronotal ground punctures as on frons, surface between ground punctures with shallow microsculpture; systematic punctures indistinct, only several coarse punctures existing on the middle of the lateral part. Elytral ground punctation slightly larger than that on head and pronotum, interspaces 1.4-1.6 × as large as punctures, surface between ground punctures as on the pronotum; 4 rows of systematic punctures distinct, with strongly reduced number of punctures, mesal row not reaching anterior margin, intervals without coarse punctures. Prosternum slightly convex, without carina medially. Mesoventrite (Fig. 4E ) with distinct, flexuose and narrow mesal carina. Metaventrite distinctly convex mesally, with a small glabrous area posteromedially.

Legs. Pubescence present on about 2/3 of femora (Fig. 4G, H, I ), hairline oblique on pro- and mesofemora, slightly oblique on metafemora.

Abdomen. Ventrite 5 (Fig. 4F ) densely pubescent, apical emargination semicircular, with a row of strong setae.

Aedeagus (Fig. 7B ). Length: 0.33mm. Phallobase about 2/3 × as long as the parameres, manubrium blunt basally. Apex of parameres truncate, almost flat, weakly inclining toward midline; lateral margin straight, with indistinct subapical constriction; inner margin slightly concave subapically; basal portion extending into about half of phallobase. Median lobe wider than paramere, apical third gradually narrowing apicad, apex bluntly rounded; corona large, locating at the basal third; basal apophyses moderately short, bending laterad; reaching third of the phallobase.

Etymology.

This species is named after Dr. Albrecht Komarek, a specialist in Hydrophilidae , who works at Naturhistorisches Museum, Wien, Austria.

Distribution.

Only known type locality.

Remark.

This species belongs to the group of species entirely chagrinate clypeus and unicolorous maxillary palpomere 4, together with A. igneus Komarek & Hebauer, A. umbrosus Komarek & Hebauer, A. gracilipalpis Komarek & Hebauer and A. schoenmanni Komarek & Hebauer. It differs from A. igneus by eight antennomeres (nine antennomeres in A. igneus ), pronotum without anterolateral chagrination, lateral margin of parameres straight and parameres slightly constricted subapically (lateral margin of parameres strongly sigmoid and with distinct subapical constriction in A. igneus ), from A. umbrosus by eight antennomeres (nine antennomeres in A. umbrosus ) and parameres moderately narrow, lateral margin straight with indistinct subapical constriction (Parameres moderately wide; lateral margins very slightly curved with distinct subapical constriction in A. umbrosus ), from A. gracilipalpis by eight antennomeres and lateral margin of parameres with indistinct subapical constriction and median lobe with apical third gradually narrowing apicad (lateral margin of parameres with distinct supapical constriction and median lobe with margins of ventral face converging to narrow, parallel-sided apical half in A. gracilipalpis ), from A. schoenmanni by eight antennomeres (nine antennomeres in A. schoenmanni ), lateral margin of parameres straight with indistinct subapical constriction and median lobe with corona locating at the basal third (lateral margins of aedeagus distinctly sigmoid with strong subapical constriction and median lobe with corona located at apical third in A. schoenmanni ). Very similar to A. reticuliceps , differs in its small size, entire chagrinate clypeus, eight antennomeres (nine antennomeres in A. reticuliceps ), median lobe with apical third gradually narrowing apicad and bluntly rounded apically (median lobe apex globular, with subapical constriction in A. reticuliceps ).

Figures

Figure 1. Habitus: A, B. Agraphydrus dapengensis sp. nov. C, D. Agraphydrus komareki sp. nov.

Figure 4. Agraphydrus komareki sp. nov.: A. Clypeus; B. Antennae; C. Maxillary palpi; D. Mentum; E. Mesoventrite; F. Ventrite 5; G. Profemora; H. Mesofemora; I. Metafemora.

Figure 7. Aedeagi: A. Agraphydrus dapengensis sp. nov.; B. Agraphydrus komareki sp. nov.; C. Agraphydrus pseudoniger sp. nov.; D. Agraphydrus sabulosus sp. nov.