Zelia, Robineau-Desvoidy, 1830

Santis, Marcelo Domingos De, O’Hara, James E. & Couri, Márcia Souto, 2024, Partial revision of the exclusively Neotropical species of Zelia Robineau-Desvoidy, 1830 (Tachinidae: Dexiinae: Dexiini), with the description of a new species, Zootaxa 5419 (1), pp. 1-52 : 7-8

Key to both sexes of Neotropical species of Zelia (including the species with New World distribution)

1 - Abdominal tergites 3 and 4 each with at least two pairs of decumbent discal setae ( Fig. 17A, C )....................... 2

- Abdominal tergite 3 bare, or with one pair of erect discal setae ( Z. varipennis ) and tergite 4 bare or with one to three pairs of decumbent discal setae................................................................................. 3

2 - Eyes with setulae ( Fig. 17A, B )....................................... Zelia pulchra (Townsend, 1919) comb. nov.

- Eyes bare........................................... Z. discalis group of species (see key of Dios & Santis, 2019)

3 - Face with facial carina well developed, dividing the antennae ( Fig. 3B )......... Zelia obscura ( Walker, 1853) comb. nov.

- Face without facial carina, at most with a small mid-level elevation (e.g., Fig. 15B )................................. 4

4 - Abdomen elongate and conical, about twice the length of thorax, with brownish median longitudinal vittae equal-sized along syntergite 1+2 to tergite 4, without silvery pruinosity dorsally in male (see fig. 7 of Nihei & Pavarini, 2011).................................................................................. Zelia angusta ( Perty, 1833) comb. nov.

- Abdomen not elongate or conical, at most 1.5x the length of thorax, with brownish median longitudinal vittae in various sizes, usually as a triangle on posterior margin of tergite 3 to 4, with silvery pruinosity dorsally in male (e.g., Fig. 6A, C )........ 5

5 - Abdomen entirely covered with silver pruinosity.................................. Zelia wildermuthii Walton, 1914

- Abdomen with silver pruinosity only on anterior half, sometimes reaching about 4/5 of abdominal segments laterally (e.g., Fig. 13A, C )............................................................................................. 6

6 - Abdomen blackish in ground color in female, Wing smoky in both sexes (e.g., Fig. 23A, C ).......................... 7

- Abdomen tawny, reddish to brownish in female, Wing hyaline in both sexes (e.g., Fig. 11A, C )........................ 9

7 - Abdominal tergite 5 light brown, but golden pruinose laterally, as viewed posterodorsally, in female ( Fig 15A, C )................................................................................... Zelia potens ( Wiedemann, 1830)

- Abdominal tergite 5 reddish to blackish in ground color, with or without silver pruinosity in female.................... 8

8 - Abdomen entirely blackish, broad in female, head with palpus strongly clavate in female ( Fig. 23 )..... Z. infuscata sp. nov.

- Abdomen blackish, but brownish tinged anteriorly, somewhat conical in female ( Fig. 19A, C ), head with filiform palpus in female, at most slightly clavate ( Fig. 19 ).............................. Zelia ureophila ( Townsend, 1928) comb. nov.

9 - Thorax reddish to reddish black in female ( Fig. 8A, C ), without median marginal setae or a weak pair present in male ( Fig. 6A ).............................................................. Zelia pickeli ( Townsend, 1935) comb. nov.

- Thorax blackish to tawny in female, with well developed median marginal setae, in male........................... 11

10 - Head mostly silvery pruinose but with about 1/4 of the dorsal portion of fronto-orbital plate golden pruinose ( Fig. 11A–C )... .................................................................................................. 12

- Head entirely silvery pruinose (e.g., Fig. 13A, B )........................................................... 13

11 - Abdomen entirely dark reddish in ground color, broad ( Fig. 11A, C )................. Zelia plumosa ( Wiedemann, 1830)

- Abdomen with syntergite 1+2 to tergite 4 dark brown and tergite 5 reddish in ground color, somewhat conical ( Fig. 1A, C ).......................................................................... Zelia limbata ( Wiedemann, 1830)

12 - Abdomen light reddish to reddish-brown in ground color in female, with abdominal tergites 3 and 4 with a strong and long pair of discal setae each ( Fig. 21A, C )....................................... Zelia varipennis (Wulp, 1891) comb. nov.

- Abdomen brownish black, tawny or dark reddish in ground color in female, both sexes with abdominal tergites 3 and 4 without discal setae, but if present then bearing at least two pairs of decumbent discal setae increasing in size anteriorly......... 14

13 - Abdomen dark reddish to dark brown in ground color both sexes with abdominal tergite 5 reddish on posterior half ( Fig. 18A, C )................................................................................................ 15

- Abdomen tawny to yellowish in ground color with abdominal tergite 5 light brown to blackish ( Fig. 10A, C )............ 16

14 - Abdomen brownish black in ground color, female with thorax with postsutural region and scutellum light brown ( Fig. 18A, C )............................................................................ Z. spectabilis (Wulp, 1891)

- Abdomen dark reddish in ground color, female with thorax with postsutural region and scutellum reddish.......................................................................................... Zelia tricolor ( Coquillett, 1899)

15 - Male with abdominal syntergite 1+2 to tergite 4 with median dorsal brownish vitta reaching both anterior and posterior margins, with tergite 3 without discal setae and abdominal tergite 5 blackish........................ Zelia vertebrata ( Say, 1829)

- Male with abdominal syntergite 1+2 to tergite 4 with median dorsal brownish vitta reaching posterior margin only, tergite 3 with a pair of decumbent discal setae increasing in size anteriorly and abdominal tergite 5 light brown ( Fig. 10A, C )............................................................................................ Zelia picta ( Bigot, 1889)

Figures

FIGURE 1. Zelia limbata (Wiedemann, 1830), female from Amazonas (INPA). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus.

FIGURE 3. Zelia obscura (Walker, 1853), holotype male (NHMUK). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus. D. Labels.

FIGURE 6. Zelia pickeli (Townsend, 1935), male from Rio de Janeiro (MNRJ). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus.

FIGURE 8. Zelia pickeli (Townsend, 1935), female from Rio de Janeiro (MNRJ). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus.

FIGURE 10. Zelia picta (Bigot, 1889), holotype male (NHMUK). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus. D. Labels.

FIGURE 11. Zelia plumosa (Wiedemann, 1830), female from Amazonas (INPA). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus.

FIGURE 13. Zelia potens (Wiedemann, 1830), male from Espírito Santo (MZSP). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus.

FIGURE 15. Zelia potens (Wiedemann, 1830), female from Rio de Janeiro (MZSP). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus.

FIGURE 17. Zelia pulchra (Townsend, 1919), holotype female (USNM). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus. D. Labels.

FIGURE 18. Zelia spectabilis (Wulp, 1891), holotype female (NHMUK). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus. D. Labels.

FIGURE 19. Zelia ureophila (Townsend, 1928), female from Brazil (CEIOC). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus.

FIGURE 21. Zelia varipennis (Wulp, 1891), holotype female (NHMUK). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus. D. Labels.

FIGURE 23. Zelia infuscata sp. nov., paratype female (MZSP). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus.