Rhyparus merkli, Minkina & Anichtchenko, 2022

Minkina, Ÿukasz & Anichtchenko, Alexander, 2022, Studies on genus Rhyparus Westwood, 1845 (Coleoptera: Scarabaeidae: Aphodiinae) with description of two new species from Southeast Asia, Baltic Journal of Coleopterology 22 (1), pp. 175-183 : 176-178

Rhyparus merkli sp. nov.

( Figs 1–3 , 7 , 9, 11 )

Type locality. Malaysia, Pahang, Cameron Highlands, Tanah Rata .

Type material. Holotype (): Malaysia, Pahang, Cameron Highlands, Tanah Rata , from illuminated, white­washed walls, 23.­ 31.iii.1995, leg. O. Merkl [ ISEA] . Paratypes (6 exx.): 4 exx.: Malaysia, Pahang, Cameron Highlands , 2km S Tanah Rata on Tapah Road, montane rainforest, 29.iii. 1995, leg. O. Merkl & Szikossy [2 exx. ISEA, 1 ex. Ÿ MCN, 1 ex. DUBC] ; 1 ex.: Malaysia, Pahang, Cameron Highlands, Tanah Rata , edge of degraded rainforest, at light, 21.iii.­ 2.iv.1995, leg. O. Merkl [ ISEA] ; 1 ex.: W Malaysia: Perak, Cameron Highlands , v.1985, leg. Wong [ ISEA] .

Description. Dorsum ( Fig. 1 ). Body length of holotype 6.0mm. Moderate in size as member of the genus. Elongate­oval, except of preapical parts of elytra, inner part of legs and strongly convex elements as costae – mat, brownishblack; except punctures, tops of costae and legs glabrous.

Head ( Fig. 7 ) trapezoidal, clypeus anteriorly truncate, with indistinct teeth on sides, laterally distinctly emarginated and next with widely rounded angles, relatively distinctly separated from distinctly protruding, rounded genae. Clypeocentral disc distinctly convex, ringed by deep grove, with pair of distinct, moderately convex, shiny only on top, somewhat longitudinal tubercles. Clypeocentral disc relatively sparsely punctate. Frons with four short, relatively narrow longitudinal costae. Punctation of head relatively regular, all punctures bearing short macrosetae.

Epipharynx ( Fig. 11 ) distinctly transverse, rather distinctly sinuate at middle, corypha with several long celter, with two lateral lobes bearing tuft of smaller and finer celtes. Epitorma broad, somewhat oval­shaped, with dense chaetopedia laterally. Tormae moderately long.

Pronotum transverse, with six distinct, costae and seven longitudinal intercostae; on each side of costae there is row of short and small yellowish macrosetae. Lateral margin with two distinctly protruding lobes; anterior lobes sharply triangular, much more developed than broadly triangular posterior. Paramedian costae continuous, almost parallel. Discolateral costae relatively widely interrupted in apical half. Median intercosta with relatively dense, but concentrated medially, medium sized punctures, lateral intercostae almost without punctures.

Scutellum almost imperceptible. Elytra elongate, relatively wide, widest before the middle. Each elytron with five distinct costae and five intercostae; on each side of costae there is row of short and small yellowish macrosetae. Fourth costae widened basally; covered by relatively dense, moderately large punctures. Intercostae flat, all of them with two rows of medium sized punctures. Postdiscal bulbs relatively small. Caudal bulbs well developed; external protrusion distinctly divided from median and internal which are fused into one and visible as one not so large elongately­spherical bulb. Pygidium with elevated area basally; medially with relatively deep grooves on sides.

Minkina Ł., Anichtchenko A.

Macropterous.

Venter matt, brownishblack ( Fig. 2 ). Meso­metaventral plate flat, with distinct, relatively shallow, wide median impression in basal 2/3; relatively densely covered by medium sized punctures bearing very thin macrosetae.Abdomal ventrites separated by relatively large, irregular in shape impressed sutures.

Legs sturdy, matt, with a lot of small punctured with eracted short setae. Mesofemora with two distinct teeth on basal border; metafemora with two indistinct teeth there. All femora with dense, not so fine, quite regular punctation bearing very thin macrosetation. Protibia tridentate apically, straight, with distinct, relatively large first dent. Mesotibiae narrow at base, widest before middle of length, and next narrowed to apex; at apex with widened apical projection. Metatibiae with similar structure as mesotibiae, but widest nearby middle of length and with more distinctly developed apical projection. Metatibiae as general with distinct sinuations.

Aedeagus ( Fig. 9 ) Phallobase much longer than parameres, moderately de­curved toward apex in lateral view. Parameres small, thin, semitransparent, visible as weak protrusion of each side of median lobe.

Variability. Body length: 5.8­ 6.3mm. Punctation of intercostae of pronotum is slightly variable. Shape of caudal bulbs is slightly variable: sinuation between median and internal protrusion is somewhat variable, sometimes it is well visible, and sometimes sinuation is weak.

Sexual dimorphism. Characteristic for genus. Visible in shape of meso­ and metatibiae as larger sinuosity and flattening with presence of elongate projection at apex in males.

Etymology. Patronymic. Name of newly described species is dedicated to its collector and our colleque who passed away some time ago: Otto Merkl.

Affinity. Because of compilation of features, i.e. relatively medium size of body; well­developed lateral lobes of pronotum, with anterior lobe distinctly larger than posterior; relatively short and wide elytra, each intercostae of elytra with two rows of medium sized punctures and external protrusion of caudal bulbs distinctly, sinuately divided from median this species can be confuzed only with R. denticollis Fairmaire, 1893 (see fig. 13) and R. mindanaoensis Anichtchenko et al., 2021 (see Anichtchenko et al., 2021: figs 5a­c, 11, 17, 23, 29a­b). From both species can be easily distinguished by punctation of intercostae of pronotum ( R. denticollis have all intercostae densely punctate; R. mindanaoensis have median intercosta similarly, but much more densely punctate and third intercostae with small area with dense punctation in basal part) and shape of caudal bulbs ( R. denticollis as well R. mindanaoensis have median and internal protrusions of caudal bulbs well distinguishable, with more or less distinct sinuation between them) (compare figs: 1, 13 and 5a fromAnichtchenko et al., 2021).What interesting aedeagus of R. merkli sp. nov. is more distinctly de­curved than aedeagus of R. denticollis and R. mindanaoensis (compare figs: 9 and 29a from Anichtchenko et al., 2021) – what is relatively rarely observed distinguishal feature among genus Rhyparus .

Figures

Figs 1–3. Rhyparus merkli sp. nov.,, holotype: 1 – dorsal view, 2 – ventral view, 3 – lateral view (scale lines: 1.0 mm).

Figs 7, 8. Heads: 7 – Rhyparus merkli sp. nov., 8 – R. jakli sp. nov. (scale lines: Fig. 7: 0.5mm, Fig. 8: 1.0mm).

Figs 9–12.Aedeagi and epipharyngi:9 – aedeagus of Rhyparus merkli sp. nov., 10 – aedeagus of R. jakli sp. nov., 11 – epipharynx of R. merkli sp. nov., 12 – epipharynx of R. jakli sp. nov. (scale lines: Figs 9, 10: 0.5mm, Figs 11, 12: 1.0mm).