Murmidius rectistriatus Lewis, 1888

Jałoszyński, Paweł & Ślipiński, Adam, 2022, Revision of the family Murmidiidae (Coleoptera: Coccinelloidea), Zootaxa 5109 (1), pp. 1-102 : 51-53

Murmidius rectistriatus Lewis

( Figs 149–155 )

Murmidius rectistriatus Lewis, 1888: 243 .

Type material examined. Holotype ( Mexico): unknown sex, “Type”, “Murmidius sp. n. / Mexico, 26.i.89”, “sp. figured”, “ Murmidius / rectistriatus Lewis / Type”, “B.C.A., Coll. II(1)” ( BMNH).

Additional material examined. Mexico: 1 ♂, 1 ex. of unknown sex; Nuevo Leon, Chipinque Mesa , near Mon- terrey, 4000 ft., 24-26.v.1971, under oak bark, leg. A. Newton ( FMNH) .

Emended diagnosis. Body short, oval, weakly convex, umbra brown; antennal club slightly elongate; anterior clypeal margin smooth; pronotum lacking lateral and sublateral longitudinal impressions; entire dorsum with superficial traces of microreticulation, most distinct but extremely fine on head, least distinct on elytra, dorsum moderately glossy; pronotum with distinct and dense punctures, small on median region and distinctly larger on sides; each elytron with nine longitudinal rows of small and shallow but distinct punctures, on interstices with additional, smaller punctures; prosternal carinae long, anteriorly reaching or slightly exceeding middle of prosternum; mesoventral plate with broadly and evenly rounded anterior margin, lacking submarginal carina, with short lateral carinae not reaching anterior mesoventral margin; elytral epipleura not narrowed at the level of metaventrite and narrow, near middle narrower than width of mesofemur; metaventrite with large, partly foveate punctures on sides; penis moderately slender and subcylindrical, in lateral view weakly curved in proximal third and nearly straight in distal 2/3; in ventral view gradually and weakly narrowing from proximal region to rounded, blunt apex; tegmen slender, with rounded apex lacking setae.

Redescription. BL 1.33–1.35 mm; BL/EW 1.46–1.47. Body short, oval ( Figs 149–150 ) and in lateral view weakly convex ( Fig. 152 ); pigmentation brown with umbra hue, legs indistinctly lighter than dorsum; dorsum very finely setose (setae whitish and well-visible under magnification 40 ×) and moderately glossy, with traces of fine microreticulation on head, and even less distinct and diffuse microsculpture on pronotum and elytra, lacking closed meshes, least distinct on elytra.

Head 0.35–0.36 mm wide, entirely finely microreticulate but not matt; frons and vertex weakly convex, with very fine and dense punctures, on median area of frons separated by spaces subequal to diameters of punctures; clypeus similarly microreticulate as frons and vertex; eyes large, strongly convex, coarsely faceted. Antennal club weakly elongate ( Fig. 150 ).

Pronotum ( Figs 149–150 ) strongly transverse, widest at base; PL 0.25 mm, PW 0.68–0.70 mm, PL/PW 0.36– 0.37; lateral margins weakly rounded and moderately strongly convergent anterad, with narrow lateral carinae; mesal corners of antennal cavities distinctly but weakly projecting anterad; lateral and sublateral longitudinal impressions lacking; anterior pronotal margin lacking marginal line. Punctures on disc fine but dense on median region, where shallow circular punctures are separated by spaces subequal to their diameters, sides in anterior half or 2/3 covered with much larger, but similarly shallow, slightly elongate punctures, also separated by spaces about as wide as their diameters.

Prosternum ( Fig. 151 ) with very fine, nearly isodiametric to slightly transverse microreticulation all over, and with fine, indistinct setiferous punctures; prosternal carinae reaching or slightly exceeding half of prosternum; notosternal carinae indistinctly sinuate and not reaching anterior prosternal margin, the latter lacking marginal carina or with indistinct trace of submarginal line.

Elytra ( Figs 149–150 ) together oval, with strongly rounded sides, broadest slightly in front of middle, EL 1.00– 1.03 mm, EW 0.90–0.93 mm, EL/EW 1.11. Humerus with distinct, prominent callus; each elytron with nine lon- gitudinal rows of small and shallow but distinct punctures, interstices between rows covered with slightly smaller, dense punctures, especially on anteromedian region.

Hind wings present and functional.

Mesoventral plate ( Fig. 153 ) with short lateral longitudinal carinae not reaching anterior mesoventral margin; anterior margin broadly and evenly rounded, lacking submarginal carina.

Metaventrite ( Fig. 153 ) with sparse and unevenly distributed large, partly alveolate punctures on sides; large median area with fine, inconspicuous setiferous punctures. Discrimen externally indiscernible.

Tarsi with short, inconspicuous setae on tarsomeres 1–3.

Aedeagus ( Figs 154–155 ) 0.35 mm long, slender; penis nearly tubular, in lateral view weakly curved in proximal third and nearly straight in distal 2/3; in ventral view gradually and weakly narrowing from proximal region to rounded, blunt apex; tegmen slender, with rounded apex lacking setae.

Distribution. Neotropical ( Mexico).

Remarks. Murmidius rectistriatus is the only species with adults having distinct rows of punctures on the elytra, but lacking lateral pronotal impressions.

Figures

FIGURES 149–155. Morphological structures of Murmidius rectistriatus Lewis. Body in dorsal (149–150), ventral (151) and lateral (152) views; pterothorax in ventral view (153); and aedeagus (154–155).