Lenziella

Giłka, Wojciech, 2011, Six unusual Cladotanytarsus Kieffer: towards a systematics of the genus and resurrection of Lenziella Kieffer (Diptera: Chironomidae: Tanytarsini), Zootaxa 3100, pp. 1-34 : 30-31

Key to adults of Lenziella

1. Tibial apices of middle and hind leg distinctly enlarged, forming stout lobes ( Figs 2 C, D; 4B–E; 5, 8, 11, 12: B, C); inferior volsella with globular swelling ventrally ( Figs 2 H, 4K, 5G, 8G, 11G, 12H); sternite VIII with several setae placed in longitudinal rows under vaginal floor close to median margins or directly on vaginal margins; labia extensive, protruding beyond posterior margin of SVIII ( Figs 6 A, B; 9A–D; 13A, B): Cladotanytarsus (Lenziella) .................................... 2

–. Tibial apices of middle and hind leg never distinctly enlarged; inferior volsella without globular swelling ventrally; sternite VIII occasionally with few setae dispersed under vaginal floor; labia fine, never protruding beyond posterior margin of SVIII, often drawn out into finger-like lobes [see Bilyj & Davies (1989, figs 9–17)]: Cladotanytarsus (Cladotanytarsus) , not keyed.

2. Antenna with 10–13 flagellomeres, proximal and/or distal flagellomeres indistinctly separated or fused, plume showing tendency for reduction, setae short and/or sparse ( Fig. 2 A; Giłka 2001, fig. 10A). Males ............................... 3

–. Antenna with 4 or 5 flagellomeres, proximal flagellomere/s/ indistinctly separated, plume absent. Females .............. 8

3. Anal point extraordinarily broad, trapezoid ( Fig. 8 D, E); hind tibia with single stout bristle apically ( Fig. 8 C)............................................................................................ C. (L.) latissimus sp. nov.

–. Anal point slender, subtriangular, lanceolate or club-shaped but never trapezoid ( Figs 2 E, F; 4F, G; 5, 11, 12: D, E); hind tibia without single stout bristle apically ( Figs 2 D; 4D, E; 5, 11, 12: C).............................................. 4

4. Inner setae (4–6) placed on prominent lobe at base of superior volsella ( Fig. 5 D); anal point spinulae small or absent and replaced with setae ( Fig. 5 D, E); tibial spurs and combs absent ( Fig. 5 A–C)................. C. (L.) crusculus (Saether)

–. Inner setae (3, exceptionally 4) placed on small protuberance at base of superior volsella, anal point spinulae distinct, never replaced with setae ( Figs 2 E, F; 4F, G; 11D, E; 12: D, E, F); tibial spurs and combs reduced or vestigial but usually present on middle or/and hind leg ( Figs 2 C, D; 4B–E; 11, 12: B, C)...................................................... 5

5. Superior volsella slightly narrowed in median part and distinctly swollen apically ( Fig. 2 E); hind tibia with tuft of long and finely bent setae ( Fig. 2 D)........................................................ C. (L.) bicornutus (Kieffer)

–. Superior volsella strongly narrowed in distal half and finely swollen apically (Figs 4F, H; 11D; 12 D, F); hind tibia with relatively short or/and strongly curved setae (Figs 4D, E; 11C; 12C)................................................ 6

6. Anal point stout, parallel-sided or somewhat lanceolate (Fig. 4F, G)........................ C. (L.) amandus Hirvenoja

–. Anal point slender, subtriangular ( Figs 11 , 12 : D, E).......................................................... 7

7. Stem of median volsella distinctly bent at base, with strongly curved furcate lamellae, stem distinctly longer than lamellae ( Fig. 11 F).......................................................................... C. (L.) piniger sp. nov.

–. Stem of median volsella straight or slightly bent, with slightly curved furcate lamellae, stem as long as lamellae ( Fig. 12 G)............................................................................... C. (L.) subletteorum sp. nov.

8. Hind tibia with single stout bristle apically; labia with posteromedian margins concave or irregularly rounded caudally, gonapophysis VIII relatively weak ( Fig. 9 A–D).......................................... C. (L.) latissimus sp. nov.

–. Hind tibia without stout bristle apically; labia with posteromedian margins parallel-sided, smoothly rounded caudally, gonapophysis VIII extensive ( Figs 6 , 13 : A, B)................................................................... 9

9. Vaginal floor moderately wide, covering about one-sixth of anterior part of vagina ( Fig. 6 A, B)........................................................................................................ C. (L.) crusculus (Saether)

–. Vaginal floor large, covering over one-third of anterior part of vagina ( Fig. 13 A, B).......... C. (L.) subletteorum sp. nov.

Figures

FIGURE 2. Cladotanytarsus (Lenziella) bicornutus (Kieffer, 1922), male. A: antenna with fused flagellomeres and reduced plume; B – D: tibial apices of fore leg (B), middle leg (C) and hind leg (D) (variation); E: hypopygium; F: anal point (variation); G: median volsella (magnified x 2 relative to hypopygium); H: inferior volsella with ventral swelling.

FIGURE 5. Cladotanytarsus (Lenziella) crusculus (Saether, 1971), male. A – C: tibial apices of fore leg (A), middle leg (B) and hind leg (C); D: hypopygium; E: anal point (variation); F: median volsella (magnified x 1.5 relative to hypopygium); G: inferior volsella with ventral swelling.

FIGURE 6. Cladotanytarsus (Lenziella) crusculus (Saether, 1971), female. A: genitalia, B: gonapophysis VIII, labia and coxosternapodeme bridge (magnified).

FIGURE 8. Cladotanytarsus (Lenziella) latissimus sp. nov., male. A – C: tibial apices of fore leg (A), middle leg (B) and hind leg (C); D: hypopygium; E: distal portion of anal point (magnified); F: median volsella (magnified x 2 relative to hypopygium); G: inferior volsella with ventral swelling.

FIGURE 9. Cladotanytarsus (Lenziella) latissimus sp. nov., variation in female genitalia. A, B: genitalia; C, D: gonapophysis VIII, labia and coxosternapodeme bridge (magnified). A, C: typical form; B, D: variation.

FIGURE 11. Cladotanytarsus (Lenziella) piniger sp. nov., male. A – C: tibial apices of fore leg (A), middle leg (B) and hind leg (C) (variation); D: hypopygium; E: anal point (variation); F: median volsella (magnified x 1.5 relative to hypopygium); G: inferior volsella with ventral swelling.

FIGURE 12. Cladotanytarsus (Lenziella) subletteorum sp. nov., male. A – C: tibial apices of fore leg (A), mid leg (B) and hind leg (C); D: hypopygium; E: anal point (variation); F: superior volsella, digitus and inner setae (variation); G: median volsella (magnified x 1.5 relative to hypopygium); H: inferior volsella with ventral swelling.

FIGURE 13. Cladotanytarsus (Lenziella) subletteorum sp. nov., female. A: genitalia, B: gonapophysis VIII, labia and coxosternapodeme bridge (magnified).