Urytalpa

Kjaerandsen, Jostein, Martinsson, Svante, Hedmark, Kjell & Evenhuis, Neal L., 2009, On the genus Urytalpa Edwards (Diptera: Keroplatidae) in the Nordic and Nearctic regions, with fixation of a new type species and a key to world males, Zootaxa 2160 (1), pp. 29-50 : 48-49

Key to males of Urytalpa

The key is partly compiled from different partial keys by Zaitzev (1994), Uesugi (2004) and Bechev & Koç (2008), but we put more focus on the male terminalia. Hence, we exclude Urytalpa maritima from the key since its terminalia has not been illustrated and the holotype has lost its abdomen (see Bechev & Koç 2008).

1. Tergite IX prolonged caudally into large, broad lateral lobes, strongly setose on medial side (cf. Fig. 8A ); aedeagal apparatus not more than twice as long as segment IX ................................................................................................. 2

- Tergite IX smaller, at most with narrow and less setose, digitate projections (cf. Fig. 5C ) or retracted, incurved lobes; aedeagal apparatus of variable length .......................................................................................................................... 3

2. Thin, slender species with long antenna ( Fig. 2D ), second flagellomere more than 2.5 times longer than broad ........ ...................................................................................................................................................... Urytalpa macrocera

- Less slender species, second flagellomere at most twice as long as broad ................................................................... ................................................................................................................ Urytalpa attenuata Zaitzev & Menzel, 1996

3. Gonocoxites completely separated ventromedially by a membranous area (cf. Fig. 7A ) .......................................... 4

- Gonocoxites connected by a narrow, sclerotized strip (H-shaped, cf. Fig. 10A ) or solidly fused medially (wide subrectangular, cf. Fig. 9A ) .............................................................................................................................................. 8

4. Large, L-shaped projection separately situated laterally between tergite IX and gonocoxites ( Uesugi 2004: figs 1A–D) .................................................................................................................. Urytalpa crassicauda Uesugi, 2004

- Without such separately situated, L-shaped projection ............................................................................................... 5

5. Mouthparts slightly elongated (cf. Uesugi 2004: fig. 4F); gonocoxites without digitate process .............................. 6

- Mouthparts not elongated; gonocoxites apicolaterally with digitate process (cf. Fig. 7A ) ........................................ 7

6. Anterior margin of tergite IX deeply emarginated, making tergite IX medially connected by a narrow strip only ( Chandler 1994: fig. 19) ...................................................................................... Urytalpa nussbaumi Chandler, 1994

- Tergite IX only shallowly emarginated anteriorly and broadly connected medially ( Uesugi 2004: fig. 4B) ................ ........................................................................................................................................................... Urytalpa yoshidai

7. Apical process from gonocoxite long, club-shaped and gently incurved in ventral view ( Fig. 7A ); tergite IX concave, with deeply u-shaped posterior edge ( Fig. 7B ); gonostylus with plain digitate projection apically ( Fig. 7D ) .............. .................................................................................................................................................. Urytalpa galdes , sp. n.

- Apical process from gonocoxite shorter, parallel sided and straight in ventral view; tergite IX convex, without deeply u-shaped posterior edge; gonostylus with characteristic hoe-shaped projection subapically ( Bechev & Koç 2008: figs 16–19) ............................................................................................................................ Urytalpa chandleri

8. Gonostylus small (cf. Fig. 6D ), shorter than sternite IX and usually retracted into gonocoxites (cf. Fig. 6A ); gonocoxites fused, H-shaped by narrow bridge medially; aedeagal apparatus more than twice as long as segment IX (cf. Fig. 5A ) ....................................................................................................................................................................... 9

- Gonostylus larger (cf. Fig. 9D ), longer than sternite IX and exposed and distinctly bifurcated in lateral view (cf. Fig. 9C ); gonocoxites fused, wide subrectangular with broad bridge medially; aedeagal apparatus less than twice as long as segment IX (cf. Fig. 9A ) ....................................................................................................................................... 13

9. Abdomen distinctly petiolated and laterally compressed ( Fig. 2A ) due to a huge vertically oriented aedeagal plate internally ( Fig. 6C ) .................................................................................................................................................... 10

- Abdomen subcircular in cross section, not distinctly petiolated nor laterally compressed; internal aedeagal plate long, but more narrow ............................................................................................................................................... 11

10. Head dark, thorax with dark brown thoracic stripes ......................................................................... Urytalpa dorsalis

- Head and thorax yellow ......................................................................... Urytalpa corniculata ( Ostroverkhova, 1979)

11. Gonocoxites with mesially directed, incurved projection ventrad of the gonostylus, projection with row of 5–6 strong setae ventrally ( Fig. 10A ); tergite IX without projections .................................................... Urytalpa trivittata

- Gonocoxites without such projection ventrad of the gonostylus, projection situated laterad of the gonostylus and slightly diverging ....................................................................................................................................................... 12

12 Tergite IX with broad, incurved projection curving mesially under proctiger and cerci; gonostylus small, digitate ( Uesugi 2004: figs 2A–F) .......................................................................................................... Urytalpa sapporoensis

- Tergite IX with narrow, digitate, straight projection apically ( Figs 5B–C ); gonostylus larger, with brush of strong setae on basal projection ( Fig. 5D ) ..................................................................................................... Urytalpa atriceps

13 Gonocoxal bridge constricted medially making apical margin between base of gonostyles widely u-shaped ( Fig. 9A ) .............................................................................................................................................................. Urytalpa nigrita

- Gonocoxal bridge not constricted medially, apical margin between base of gonostyles straight ( Chandler 1995: fig. 1) ................................................................................................................................................... Urytalpa rhapsodica

Figures

FIGURE 2. Habitus photos of males of Nordic species of the genus Urytalpa Edwards. — A. Urytalpa dorsalis (Staeger, 1840). — B. Urytalpa trivittata (Lundström, 1914). — C. Urytalpa atriceps (Edwards, 1913). — D. Urytalpa macrocera (Edwards, 1913). — E. Urytalpa galdes Hedmark & Kjaerandsen sp. n.

FIGURE 5. Male terminalia of Urytalpa atriceps (Edwards, 1913). — A. Sternite IX, hypandrial lobe and internal aedeagal apparatus in ventral view (pre-terminal segments not illustrated). — B. Tergite IX, proctiger and cerci in dorsal view. — C. Segment IX and beyond in lateral view. — D. Gonostylus in lateral view, enlarged.

FIGURE 6. Male terminalia of Urytalpa dorsalis (Staeger, 1840). — A. Sternite IX and hypandrial lobe in ventral view. — B. Tergite IX, proctiger and cerci in dorsal view. — C. Segment IX and beyond in lateral view, including internal aedeagal apparatus (pre-terminal segments not illustrated). — D. Gonostylus in lateral view, enlarged.

FIGURE 7. Male terminalia of Urytalpa galdes Hedmark & Kjaerandsen sp. n. — A. Segment IX, hypandrial lobe and internal aedeagal apparatus in ventral view (pre-terminal segments not illustrated). — B. Tergite IX, proctiger and cerci in dorsal view. — C. Segment IX and beyond in lateral view. — D. Gonostylus in lateral view, enlarged. — E. Aedeagal apparatus in lateral view.

FIGURE 8. Male terminalia of Urytalpa macrocera (Edwards, 1913). — A. Segment IX, hypandrial lobe and internal aedeagal apparatus in ventral view (pre-terminal segments not illustrated). — B. Tergite IX, proctiger and cerci in dorsal view. — C. Segment IX and beyond in lateral view. — D. Gonostylus in lateral view, enlarged.

FIGURE 9. Male terminalia of Urytalpa nigrita (Johannsen, 1910) comb. n. — A. Segment IX, hypandrial lobe and internal aedeagal apparatus in ventral view (pre-terminal segments not illustrated). — B. Tergite IX, proctiger and cerci in dorsal view. — C. Segment IX and beyond in lateral view. — D. Gonostylus in lateral view, enlarged.

FIGURE 10. Male terminalia of Urytalpa trivittata (Lundström, 1914). — A. Sternite IX, hypandrial lobe and internal aedeagal apparatus, ventral view (pre-terminal segments not illustrated). — B. Tergite IX, proctiger and cerci in dorsal view. — C. Segment IX and beyond in lateral view. — D. Gonostylus in lateral view, enlarged.