Solierodes, Ruta, 2021

Ruta, Rafał, 2021, Three new genera of large marsh beetles (Coleoptera: Scirtidae) from Valdivian temperate rain forests of southern South America, Zootaxa 5048 (4), pp. 451-485 : 458-460

Genus Solierodes gen. nov.

( Figs 1C–E , 2B , 4B , 7–9 )

Type species: Solierodes rousseli ( Solier, 1849) , by present designation.

Diagnosis. Large (TL 9.5–10.7 mm), non saltatorial, elongate, with subparallel sides of elytra, body covered with golden setae, setation of elytra in males patchy. Subantennal grooves shallow in males and moderately deep in females, subgenal ridge without buttonhole configuration. Pronotum short, in males distinctly narrower than basal portion of elytra, pronotum of females wider, slightly narrower than basal portion of elytra, with tubercles in posterior portion; anterolateral pronotal angles rounded, slightly protruding. Males: penis with bifid trigonium, parameres long, with subparallel sides and serrate margins. Females: coxites subtriangular, sclerotized, styli subapical; ventrite 4 with transverse patch of setae, ventrite 5 with elongate concavity.

Description. Male. Body ( Fig. 1C ) elongate, TL 9.5–10.7 mm, moderately convex. Colouration brown, head and pronotum covered with long, yellowish setae, setation of elytra a bit shorter, yellowish, with distinct brown patches, head and pronotum covered with dense but small punctures, elytra with slightly larger, dense punctures, punctation irregular.

Head relatively small, wider than long; eyes large and protuberant, finely facetted; tempora long, distance from posterior margin of eye to occipital ridge ca. 0.6× diameter of the eye, subparallel; distance from ventral margin of eye to subgenal ridge equal to ca. 0.3× diameter of the eye; supraantennal ridges not elevated, joined to margins of eyes; frons with two shallow depressions behind antennal insertions; subantennal grooves slightly concave, relatively shallow, glossy and impunctate, each subantennal groove separated from frons by a short ridge near supraantennal ridge, continued along margin of eye as sharp ridge, in lower portion connected with subgenal ridge. Frontoclypeal suture absent; clypeus subtrapezoidal, ca. 2.3× wider than long, with straight anterior margin, lateral margins converging posteriorly. Anteclypeus present, ca. 3× shorter than clypeus. Ventral portion of head between subgenal ridges flat, gular area convex, rectangular, slightly longer than wide. Subgenal ridge well marked, without buttonhole configuration. Antennae filiform; antennomere 1 widest, subcylindrical, slightly curved; antennomere 2 subglobular and small, distinctly narrower and ca. 3× shorter than antennomere 1; antennomere 3 long and narrow, as long as antennomere 1, slightly widening apically; antennomeres 4–10 similar to antennomere 3 but ca. 1.5× longer, apical antennomere slightly longer than penultimate one, slightly widened in apical portion. Labrum covered with long setae, transverse, ca. 2.0× wider than long, anterior margin slightly emarginated, anterolateral angles rounded. Mandibles ( Fig. 7A ) symmetrical, ca. 2.0× longer than width at bases, abruptly curved in apical 1/4, apices unidentate, outer margin covered with setae; inner margin of mandibles with big subtriangular denticle and two smaller ones; molar region with indistinct setation. Maxillary palpi ( Figs 7C ): palpomere 1 shortest, subconical, 2 longest, ca. 2.5× longer than palpomere 1, 3 ca. 3× longer than palpomere 1, 4 narrow, digitiform, almost 2× shorter than 3. Galea subrectangular, slightly longer than wide, much shorter than lacinia, with group of dense, irregularly arranged setae at apex; lacinia with dense, slightly curved setae on inner margin and apex. Mentum ( Fig. 7B ) slightly transverse (W/L = 1.6), subtrapezoidal. Prementum subtriangular strongly widening apically, apical margin straight, ligula covered with dense setae. Labial palpomeres: palpomere 1 long, narrow, sinuate ca. 3× longer than wide, sparsely covered with setae; palpomere 2 strongly widened, enlarged, subconical, as long as palpomere 1, ca. 2× longer than wide, densely covered with long setae; apical palpomere arising from apex of preapical one, narrow, slightly shorter than palpomere 2, very sparsely covered with short setae.

Pronotum small, transversely rectangular, distinctly narrower than base of elytra, ca. 2.1× wider than long; lateral carinae subtly curved; disc convex, lateral portions flattened; anterior margin rounded; anterolateral angles rounded, slightly produced; posterior angles right-angled; base curved, with distinct margination ending laterally with small shiny area with neither setae nor punctures. Prosternum reduced anteriorly; prosternal process rhomboidal, posterior apex pointed and bent ventrally, ca. 1.8× longer than wide, covered with setae.

Scutellar shield triangular, slightly longer than wide, flat, with pointed apex; anterior margin straight, impunctate, covered with weakly impressed punctures. Elytra very long, with three subtle carinae, sides subparallel, distinctly wider at base than pronotal base; slightly widened in posterior half; humeri marked, apices regularly rounded. Epipleura wide at base, slightly narrower than metanepisternum, distinctly narrowed behind metaventrite, present till apices.

Hind wings ( Fig. 4B ) ca. 2.2× longer than its width; radial cell subtriangular; apical portion of r3 well visible, straight; rp-mp2 arcuate, forming acute angle with MP 1+2; MP 4 long, oblique, joining MP 3 and CuA+AA 1+2; anal field with well marked AP 3 and AP 4. Medial field with 3 free veins; pigmented areas in radial cell, medial, radial, central and apical fields.

Mesoventrite ( Fig. 2B ) small; anterior margin with coxal rests; mesoventral process with well marked longitudinal suture; anterior portion forming deep, subtriangular fossa for reception of prosternal process; mesoventral process ca. 2.5× longer than wide, sides subparallel, apex bilobed, touching metaventrite; mesocoxae completely separated; mesanepisternum rhomboidal, covered with setae, punctate, wider than long, forming coxal rest for procoxa; mesepimeron smaller, setose, subtriangular, strongly narrowed mesally; mesocoxae subconical, slightly projecting.

Metaventrite ( Fig. 2B ) moderately long, transverse (W/L 2.6), convex; discrimen complete; metanepisternum subtrapezoidal, ca. 2× longer than its width, slightly narrowing posteriorly. Metacoxae moderately large, strongly oblique, 3.2× wider than long, extending laterally to epipleura; metacoxal plate abruptly narrowing in outer half.

Legs long; femora extending beyond elytral margin, trochanters moderately long; trochantero-femoral joint oblique; metafemora slightly shorter than metatibiae, metatibiae straight. Tibiae narrow, slightly widening towards apices, with paired carinae; length of metatibial spurs equal to largest width of metatibiae; tarsi distinctly shorter than tibiae; tarsomere 1 elongated, sides subparallel, as long as tarsomeres 2–3 combined; tarsomere 4 emarginated at apex; apical tarsomere as long as tarsomere 1, with simple claws.

Abdomen ca. 1.5× longer than its width, convex; ventrites 1–4 of subequal length; ventrite 5 slightly shorter; ventrite 5 regularly rounded at apex. Abdominal ventrites regularly covered with setae. Genitalia ( Fig. 8 ) of Microcara type, symmetrical, penis large, dorsoventrally flattened, trigonium bifid, parameroids narrow, with subparallel sides, longer than trigonium. Tegmen large, parameres wide at bases, narrowing towards apices, apices pointed, margins serrate.

Female ( Figs 1D, E ). Body large (TL 10.4–10.6 mm), covered with longer and more erect setae; head more transverse, eyes less protuberant, subantennal grooves deeper than in males; pronotum wide (PW/PL 2.2), anterolateral angles rounded, slightly more produced than in males, with paired raised protuberances in lateral portion of posterior half; scutellar shield equilaterally triangular, elytra long, with subparallel sides; ovipositor long, branchlets absent; coxites subtriangular, sclerotized, styli subapical; bursal sclerites present; ventrite 4 with transverse patch of setae, ventrite 5 with elongate concavity.

Biology. According to the original description ( Solier 1849), this species was found among scrub and on trees, together with Mucronotus velutinus (Solier) . Specimens collected in recent decades were found in Valdivian forests, in a single case a specimen was fogged from Saxegothaea conspicua Lindley (Podocarpaceae) .

Etymology. Dedicated to Antoine Joseph Jean Solier (1792–1851), to commemorate his pioneering studies on Chilean marsh beetles. The genus name is a combination of Solier’s name and ending of a genus Elodes Latreille. Gender masculine.

Figures

FIGURE 1. Dorsal view. A) Argelodes magnificus sp. nov.; B) A. magnificus, close-up of head and pronotum; C) Solierodes rousseli (Solier), male; D) S. rousseli, female; E) S. rousseli, female, close-up of head and pronotum. Scale bars (A, C, D) = 3.0 mm.

FIGURE 2. Ventral view, SEM images. A) Argelodes magnificus sp. nov.; B) Solierodes rousseli (Solier).

FIGURE 4. Wings.A) Argelodes magnificus sp. nov.; B) Solierodes rousseli (Solier); C) Mucronotus velutinus (Solier).Abbre- viations: AA—anterior anal vein, AP—posterior anal vein, CuA—anterior cubital vein, CuA+AA1+2—fusion of anterior cubital and anterior anal veins, MP—posterior medial vein, r3—third radial cross-vein, RA—anterior radial vein, rp-mp2—second radio-medial cross-vein, ScP—posterior subcostal vein.

FIGURE 7. Solierodes rousseli (Solier), mouthparts. A) mandible, molar region enlarged; B) labium; C) maxilla.

FIGURE 8. Solierodes rousseli (Solier), male. A) penis; B) tegmen; C) sternite VIII; D) sternite IX; E) tergite VIII; F) tergite IX. Scale bar = 0.5 mm.

FIGURE 9. Solierodes rousseli (Solier), female.A) genital tract; B) coxites, close-up; C) bursal sclerite; D) abdominal ventrites 4 & 5, setal patch visible. Abbreviations: as—apical setae, bscl—bursal sclerite, bsl—bursella, gla—gland, sen—sensillae, st—styli. Scale bar = 1.0 mm (figures B, C, D—not to the scale).