Quedius

Pietrykowska-Tudruj, Ewa, Czepiel-Mil, Katarzyna & Staniec, Bernard, 2014, Larval morphology of selected Quedius Stephens, 1829 (Coleoptera: Staphylinidae: Staphylinini) with comments on their subgeneric affiliation, Zootaxa 3827 (4), pp. 493-516 : 497-498

Genus Quedius

General diagnoses of mature larvae of Quedius . The diagnostic characters of the genus Quedius were determined based on morphological data extracted from descriptions by Smetana (1957, 1962), Pototskaya (1967), Frank (1969), Kasule (1970), and Staniec (2003). A combination of characters distinguishing the larvae of Quedius from other genera within the tribe Staphylinini is the following: head slightly longer than wide with frayed setae absent; nasale with 9 teeth, paramedian teeth longer than the others, teeth Lt1 longer than other lateral; antennal segment I broad at the base; stalk of apotome reaching or extending beyond tentorial pits; stipes with 9 setae and hair-like microtrichia; mala two setose, longer than segment I of maxillary palp; maxillary and labial palps 3- and 2-segmented, respectively, segment I of maxillary palp shorter than others; labium with 4 setae, ligula reaching the level of internal pores on labial palp; comb of bifurcate setae on tibia present; tarsungulus trisetose; frayed setae on meso- and metanotum present only in Q. brevis ; anterior carina on abdominal segment I present, on segments II–VIII absent; frayed setae on abdominal tergites and pygopod present; urogomphi shorter than pygopod, one (only in Q. molochinus ) or two segmented; apical seta frayed apically.

General description of larval morphology of Quedius . Colour: head brown or light brown, stemmata (if present) dark brown almost black, mandibles like head or slightly darker; pronotum yellowish brown, meso-, metanotum, and leg slightly lighter than pronotum (only in certain specimens of Q. cinctus metanotum slightly darker than mesonotum), abdominal tergites I – IX almost colourless or light brown; body white or dirty white, segment X slightly darker than abdomen, dark yellow; urogomphi slightly darker than abdominal segments, yellowish ( Q. cinctus ) or dirty white ( Q. microps ), or segment I dirty white whereas II yellowish ( Q. cruentus , Q.

brevis ); setae on all body ginger or light brown, setae on head like the head surface (merging with the head surface) excluding Q. microps (where setae are darker than the light head surface) ( Figs 1 A–E, 2A–F).

General appearance: body elongate, head slightly longer than wide, narrowing or widening from the stemmata posteriad to the base, pronotum narrower or slightly wider than head, meso- and metanotum almost equal in length and width, legs moderately long and slender, pronotum and abdominal sclerites with simple and frayed setae, respectively, urogomphi slightly or distinctly shorter than terminal segment of the body ( Figs 1 A–E, 2A–F, 11A–F, I, J).

Head: epicranial part (Ep) with 10–16 pairs of setae (5–6 of them long), and a pair of gland (Gl); posterior area (Pa) with 3 pairs of micro setae (P1–3) and a pair of pores, dorsal ecdysial suture (Des) bifurcate before half of head length (Fig. 2G). Nasale (Na) (Figs 3A–H) with: 10–11 pairs of simple setae (5 of them on anterior margin), a pair of pores medially, a pair of lateral sensilla (Sm) and a pair of olfactory organs anteriorly (Og); anterior margin with 9 teeth divided into 3 distinct clusters (one middle and two lateral), each cluster with 3 teeth, paramedian teeth (Pmt) longer than median tooth (Mt), lateral teeth Lt1 longer than Lt2 and Lt3. Antenna ( Figs 4 A–G): 4- segmented, segment I broad at the base, segments II–IV slender, segment III with 3 macro setae (one ventrolaterally and two laterally), two sensory appendages (Sa) (one large acorn-shaped or oval, and second tiny) and two solenidia (So) ventrally; segment IV longer than large sensory appendage with 3 long setae and 4 apical solenidia (So). Mandibles (Figs 5A–C): more or less slender and moderately broad at the base; with 2 setae at the outer margin [anterior (L1) shorter than posterior (L2)], two pores dorsally [dorsal (Dsm) and dorsolateral (Dlsm)], and transverse sutures (Ts). Ventral side of head (Fig. 2H) with 5–8 pairs of setae. Apotome (Apt) completely formed (Figs 5D–F), in broad outline triangular, with stalk, reaching or extending beyond tentorial pits (Tp), with 3 pairs of setae, a two pairs of sensilla (Sm). Epipharynx as in Figs 5G–I. Maxilla ( Figs 6 A–K): cardo slightly wider than long, with a seta ventrally; stipes slender, narrowed anteriad, with 9 setae (2 near inner margin, 4 near outer margin and 3 near mala), a longitudinal band of hair-like microtrichia dorsally ( Fig. 6 B). Mala (Ma) ( Figs 6 C, F, H, I, K), elongated, slightly curved inside, narrowed apically, with 2 setae (one tiny on inner margin and one ventrally) and 2–3 solenidia (1–2 apical and one subapical), longer than segment I of maxillary palp. Palpifer (Pf) ( Fig. 6 C) with a seta and a pore. Maxillary palp (Mp) ( Figs 6 C–E, G, J): 3-segmented, segment I shortest; segment II with 2 setae (one laterobasal and one lateroapical), segment III gradually narrowed to apex, with digitiform sensory appendage (Sa) on outer margin. Labium ( Figs 7 A–G): prementum ( Fig. 7 A): consist of two parts: anterior-wider, membranous with ligula (Lg) and a pair of labial palps, and posterior more or less narrower, sclerotized with 4 setae (2 long anteriorly and 2 short laterally) and 2 anterior pores; ligula (Lg) ( Figs 7 B, F, G) somehow conical or triangular, reach the level of sensillum (Sm) on segment I of labial palp, with 2 setae. Labial palp (Lp) 2-segmented ( Figs 7 B, C): segment I with one sensillum (Sm) at the inner margin, segment II slightly narrower than the first one, gradually narrowed apically. Hypopharynx ( Figs 7 D, E): dorsal side of labium membranous and densely pubescent with microtrichia (Dmt).

Thorax: fore leg ( Figs 8 A–G): coxa (Cx) moderately elongate, trochanter ( Tr) divided, femur (Fe) slender with thick, spine-shaped setae on ventral side, tibia (Tb) slender with spine-shaped setae on dorsal and ventral side and comb of bifid setae near apex ( Figs 8 D–G), tarsungulus (Tu) with 3 spine-shaped setae. Thoracal tergites with mid-longitudinal ecdysial line ( Figs 9 A–C). Pronotum: slightly narrower or wider than mesonotum, with transverse carina anterior and posterior, and simple setae. Meso- and metanotum almost equal in width ( Figs 9 B, C): rounded on sides, with transverse carina anterior and posterior, with or without frayed setae ( Figs 9 D–F). Chaetotaxy on meso- and metanotum with setae: 16–20 (7–11 anterior, 3 lateral and 6 posterior) and 19–20 (10–11 of them anterior), respectively ( Figs 9 B, C).

Abdomen: segments I–VIII each with tergite (Te) and sternite divided into two parts by weakly sclerotized, longitudinal membranous area ( Fig. 9 G). Segment I: tergite with transverse, anterior carina. Segments II–VIII: tergites without carinae, setae on tergites as on Figs 10A–R. Segment IX with a pair of urogomphi, each one with one or two segments (Figs 11A–P). Chaetotaxy of segment X and segment I of urogomphi as in Figs 11L, M, O, P. Segment II of urogomphi (if present) shorter than I with 3 setae: two micro (one simple and one frayed) and one long apical, frayed apically (Fig. 11H). Microstructure of segment I of urogomphi as in Figs 11G, K, N. Urogomphi shorter than pygopod.

Figures

FIGURE 1. Q. molochinus (A), Q. cinctus (B), Q. brevis (C), Q. cruentus (D) and Q. microps (E), mature larvae, general view.

FIGURE 4. Q. fuliginosus (A), Q. brevis (B, E, G), Q. mesomelinus (C), Q. microps (D), Q. cinctus (F), mature larvae, right antenna in dorsal aspect. A – D, general view; E, F, sensory appendage of antennal segment III; G, apex of antennal segment IV. Abbreviations: I – IV, antennal segments; Sa, sensory appendages; So, solenidium.

FIGURE 6. Q. brevis (A – F), Q. fuliginosus (G, H), Q. cruentus (I), Q. microps (J, K), mature larvae, right maxilla in dorsal aspect. A, cardo and stipes with microtrichia (B); C, G, J, maxillary palp; D, E, apex of segment III of maxillary palp; F, apex of right mala; H, K, right mala in dorsal aspect. Abbreviations: I – III, segments of maxillary palp; Cd, cardo; Dmt, dorsal microtrichia; Ma, mala; Mp, maxillary palp; Pf, palpifer; Sa, sensory appendage; So, solenidium; St, stipes.

FIGURE 7. Q. brevis (A, B), Q. microps (C), Q. mesomelinus (D), Q. fuliginosus (E, F), Q. boops (G) mature larvae, labium and hypopharynx. A, prementum with ligula in ventral aspect; B, C, labial palp in ventral aspect; D, E, hypopharynx; F, G, ligula. Abbreviations: I – II, segments of labial palp; Lg, ligula; Lp, labial palp; Pmnt, prementum; Sm, sensillum; Dmt, dorsal microtrichia.

FIGURE 8. Q. fuliginosus (A), Q. brevis (B), Q. cruentus (C, D), Q. cinctus (E – G) mature larvae, fore leg. A – D, segments of fore leg in anterior aspect; E – G, comb of bifurcate setae on tibia with code. Abbreviations: Cb, comb; Cx, coxa; Fe, femur; Tb, tibia; Tr, trochanter; Tu, tarsungulus.

FIGURE 9. Q. brevis (A – G) mature larvae, thorax and abdomen. A – C, pro- (A), meso- (B), metanotum (C) in dorsal aspect; D, setae on mesonotum; E – F, apex of setae on mesonotum; G, abdominal segment I and II in dorsal aspect. Abbreviations: I – III, segments; Te, tergite.