Agraphydrus sabulosus 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 sabulosus Yang & Jia sp. nov. Figs 2C, D ; 6 ; 7D

Type locality.

China, Guangdong Province, Fengkai County, Heishiding Nature Reserve.

Material examined.

Holotype: male (SYSU); CHINA: Guangdong Province, Fengkai, Heishiding Nature Reserve , ca 23°31'N, 111°52'E, 20-22.xii.2014, Fenglong Jia, Renchao Lin, Yudan Tang leg. Paratypes: (9 exs., IZCAS, SYSU): 4 exs., same data as holotype ; 5 exs., Jiangxi Province, Shangyou Country, Guanggushan Nature Reserve , 846m a.s.l, 25°55'11"N, 114°03'04"E, 21.vi.2015. leg. Renchao Lin, Yudan Tang.

Diagnosis.

This species is distinguished from the other species of Agraphydrus by the following combination of characters: labrum, clypeus and frons black; preocular spots present; clypeus entirely microsculptured; maxillary palpi with apical palpomere about 1.5 × as long as the penultimate one, palpomere 4 without apical infuscation; antennae with 9 antennomeres; elytra with four irregular series of coarse punctures; meso- and metafemora pubescent in about basal 2/3; aedeagus with median lobe narrowing toward the apex; parameres with obvious subapical constriction.

Description.

Form and color. Total length: 1.9-2.1 mm; elytral width: 1.0-1.1 mm; E.I.:1.1-1.3, P.I.:1.3-2.2, elytra 3-4 × as long as pronotum. Body moderately oval, moderately broad, slightly convex dorsally. Labrum and frons black, clypeus black mesally with yellow preocular patches, as wide as eyes; maxillary palpi unicolored yellow; pronotum unicolored light yellow or dark brown mesally with light red brown margin; elytra light yellow or light yellow mesally, lateral and anterioral margin black. Ventrites black; legs light to dark brown.

Head. Labrum entirely microsculptured, with several punctures at the anterior margin. Clypeus (Fig. 6A ) almost entire surface covered by microsculpture, absent only from a small posterior region; ground punctures only present at the non-microsculptured area, as on frons, interspaces 1-2 × as large as punctures; clypeus and frons with distinct systematic punctures. Eyes moderately large, distinctly protruding. Antennae (Fig. 6B ) with nine antennomeres. Maxillary palpi (Fig. 6C ) 1.2-1.5 × as long as pronotum in midline, 1.0-1.1 × as long as maximum width of clypeus; length ratio palpomere 4:3 =1.4-1.5, palpomere 4 asymmetrical. Mentum (Fig. 6D ) with several coarse punctures in lateral portion, without microsculpture.

Thorax. Pronotum ca. 3-4 × as wide as long, pronotal ground punctures as on frons and clypeus, surface between ground punctures smooth, without microsculpture; systematic punctures distinct, located at the middle of the lateral margin. Elytral ground punctures as that on head and pronotum; systematic punctures distinct, arranged into 4 rows, mesal row not reaching anterior margin, intervals without coarse punctures. Prosternum weakly convex, not carinate medially, with a transverse groove. Mesoventrite (Fig. 6E ) slightly bulged. Metaventrite with a bulge mesally, hydrofuge pubescence present on the surface, only absent from a small area on posteromedian part.

Legs. Pubescence present on proximal 2/3 of femora (Fig. 6G, H, I ), hairline oblique on pro- and mesofemora, straight on metafemora.

Abdomen. Ventrite 5 (Fig. 6F ) trapezoidal, with distinct semicircular apical emargination.

Aedeagus (Fig. 7D ). Length: 0.3 mm. The length of the phallobase 2/3 × as long as the parameres, margin distinct bend toward slender, pointed manubrium. Apex of parameres obtuse, moderately flat; lateral margin is curved in basal 3/4, sunken in apical 1/4; mesal margin slanted but straight; base extending into about 1/3 of phallobase. Median lobe wide basally, narrowing toward apex, apex delicate; corona moderately large, locating at middle of the median lobe; basal apophyses slender and moderately long, slightly bending laterad; reaching the 1/3 of the phallobase.

Etymology.

This species is named after the holotype acquisition environment, which has a lot of sand.

Distribution.

China (Guangdong, Jiangxi).

Remark.

This species shares almost entirely chagrinate clypeus and unicolored maxillary palpomere 4 with A. arduus Komarek & Hebauer, A. annapurnensis Komarek, A. connexus Komarek & Hebauer, A. flavonotus Komarek, A. gracilipalpis Komarek & Hebauer, A. gilvus Komarek, A. igneus Komarek & Hebauer, A. narusei Komarek, A. ogatai , A. orientalis Komarek & Hebauer, A. reticuliceps Komarek & Hebauer, A. schoenmanni Komarek & Hebauer, and many individuals of A. umbrosus Komarek & Hebauer. Its dorsal color is very similar to some individuals of A. connexus , differs from A. connexus by parameres with apex obtuse, moderately flat, manubrium slender and pointed (parameres with apex delicate and bluntly rounded, dorsal face connected with base of median lobe by distinct median band and the manubrium conical in the A. connexus ). Its aedeagus is very like that of A. flavonotus Komarek, from which it differs by clypeus with distinct ground punctures (ground punctures obsolete on clypeus in A. flavonotus ), four rows of systematic punctures distinct (indistinct in A. flavonotus ), mesoventrite with moderately distinct mesal bulge (strong in A. flavonotus ), apex of median lobe delicate and basal apophyses reaching the 1/3 of the phallobase (apex of median lobe flatly and the basal apophyses reaching half of phallobase in A. flavonotus ). Differs from A. arduus and A. igneus by pronotum without anterolateral chagrination, parameres with apex obtuse, moderately flat, lateral margin of the parameres slightly curved and median lobe narrowing toward apex (parameres with apex delicate, bulgy, lateral margin of parameres slightly sigmoid and median lobe with blunt or flat, rarely slightly indented apex in A. arduus , and apex of parameres strongly inflated, lateral margin of the parameres strongly sigmoid and apex of median lobe bluntly rounded with numerous distinct setae on top in A. igneus ).

Figures

Figure 2. Habitus: A, B. Agraphydrus pseudoniger sp. nov. C, D. Agraphydrus sabulosus sp. nov.

Figure 6. Agraphydrus sabulosus 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.