Murmidius elongatus, Jałoszyński & Ślipiński, 2022

Jałoszyński, Paweł & Ślipiński, Adam, 2022, Revision of the family Murmidiidae (Coleoptera: Coccinelloidea), Zootaxa 5109 (1), pp. 1-102 : 70-72

Murmidius elongatus sp. n.

( Figs 213–219 )

Type material examined. Holotype ( Brazil): sex unknown, “ Nova Teutonia, Sta. / Catarina, / Braz. / VII:27:57 / Fritz Plaumann leg.” ( MHNG) . Paratypes (15 exx): 10 exx (incl. 1 dissected ♂), same data as for holotype, except for dates: 30.08.1956, 02.07.1957, 05.07.1957, 06.07.1957, 12.07.1957, 12.08.1957, and 11.1976 ; 1 ex., “ Rio Caraguata , M. Grosso / Brazil IV:20:1953 / 21º 48’; 52º 27’; 400M. alt. / Fritz Plaumann leg.” ; 1 ex., same data except for “IV:I:1953” ; 1 ex., same data except for “III:27:1953” ; 1 ex., “Brasilien / Rondon / 24º 38’ B. 54º 07’ L, 500 m / 10:5:1957 / Fritz Plaumann ”. Argentina : 1 ex., “ Argentina / Tabillas, Salta / Harrington ” (paratypes in ANIC; FMNH, MHNG, MNHW, MIZ) .

Diagnosis. Body strongly elongate oval and moderately convex, light brown to dark, nearly black; antennal club only slightly elongate; anterior clypeal margin smooth; pronotum lacking lateral and sublateral longitudinal impressions; clypeus and especially pronotum with distinct, very fine, semi-matt to matt microreticulation, reticulation on frons and vertex variable, in some specimens poorly discernible and surface glossy, in others almost as distinct as on clypeus and semi-matt, elytra smooth and glossy; elytra with fine, superficial and dense punctures not arranged in rows; prosternal carinae about as long as 2/3 to 3/4 of prosternum (but see remarks); mesoventral plate with evenly rounded anterior margin, with distinct anterior submarginal carina but lacking lateral carinae; elytral epipleura not strongly narrowed at the level of metaventrite where they are much narrower than width of mesofemur; metaventrite with punctures on sides slightly more distinct, larger and deeper than those at middle, but not remarkably so; penis slender, in lateral view strongly curved; in ventral view penis gradually narrowing from about middle toward subtriangular, pointed apex; tegmen slender, with truncate apex bearing four pairs of long setae.

Description. BL 1.30–1.70 mm; BL/EW 1.65–1.77. Body strongly elongate oval ( Figs 213–215 ) and in lateral view moderately convex ( Fig. 216 ); pigmentation light brown to dark, nearly black; dorsum covered with short whitish setae (discernible under magnification 80 ×); clypeus and especially pronotum with distinct, very fine, semimatt to matt microreticulation, reticulation on frons and vertex variable, in some specimens poorly discernible and surface glossy, in others almost as distinct as on clypeus and semi-matt, elytra smooth and glossy.

Head 0.33–0.43 mm wide; frons and vertex weakly convex, with fine, inconspicuous punctures; clypeus matt or weakly glossy; eyes large, strongly convex, coarsely faceted. Antennal club ( Fig. 215 ) only slightly elongate.

Pronotum ( Figs 213–214 ) strongly transverse, widest at base; PL 0.28–0.33 mm, PW 0.60–0.80 mm, PL/PW 0.39–0.46; lateral margins nearly straight and moderately strongly convergent anterad, with narrow but distinct lateral carinae; mesal corners of antennal cavities weakly projecting anterad; lateral and sublateral longitudinal impressions lacking; anterior pronotal margin with distinct marginal line. Punctures on disc uniform, fine and dense but obscured by dense microreticulation.

Prosternum ( Fig. 215 ) with barely discernible transverse microreticulation and with fine, inconspicuous setiferous punctures; prosternal carinae about as long as 2/3 to 3/4 of prosternum (but see remarks) and with slightly curved outwards distal ends, in most specimens somewhat sinuate; notosternal carinae nearly straight and not reaching anterior prosternal margin, the latter lacking marginal carina.

Elytra ( Figs 213–214 ) together oval, with weakly rounded sides, broadest indistinctly in front of middle, EL 0.93–1.23 mm, EW 0.78–1.00 mm, EL/EW 1.16–1.26. Humerus with distinct callus; elytra densely punctate, but punctures small and shallow, inconspicuous, not arranged in rows, those on anteromedian region of each elytron separated by spaces subequal to their diameters, punctures reducing in depth toward sides and apices. Epipleura not narrowed near middle, but with slightly flattened, straight margins between metaventral femora lines and metacoxae.

Hind wings fully developed.

Mesoventral plate ( Fig. 217 ) lacking lateral longitudinal carinae, with distinct and complete anterior submarginal carina; anterior margin evenly, broadly rounded.

Metaventrite ( Fig. 217 ) with moderately large, not alveolate and not particularly remarkable punctures on sides; median region with fine, inconspicuous setiferous punctures. Discrimen externally poorly discernible or not marked.

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

Aedeagus ( Figs 218–219 ) 0.55 mm long, slender; penis in ventral view gradually narrowing toward from about middle toward subtriangular, pointed apex, in lateral view penis strongly curved; tegmen slender, slightly longer than half of penis, with truncate apex bearing four pairs of long setae.

Distribution. Neotropical ( Argentina, Brazil).

Etymology. The specific epithet elongatus refers to the body shape.

Remarks. The species is extremely variable in body length and pigmentation. Large specimens tend to have more distinct microreticulation of the pronotum. In all studied specimens the prosternal carinae at least slightly exceed half-length of prosternum, in most they are as long as about 2/3 up to 3/4 of prosternum. However, one speci- men was found with almost completely obliterated prosternal carinae, and therefore care should be taken to confirm all identifications by examination of the aedeagus.

Figures

FIGURES 213–219. Morphological structures of Murmidius elongatus sp. n. Body in dorsal (213–214), ventral (215) and lateral (216) views; pterothorax in ventral view (217); aedeagus (218), and isolated penis (219).