Simulium ceylonicum

Jitklang, Sanae, Kuvangkadilok, Chaliow, Baimai, Visut, Takaoka, Hiroyuki & Adler, Peter H., 2008, Cytogenetics and morphotaxonomy of the Simulium (Gomphostilbia) ceylonicum species group (Diptera: Simuliidae) in Thailand, Zootaxa 1917, pp. 1-28 : 24

Key to pupae of 10 cytoforms in the S. ceylonicum group in Thailand *

( Fig. 11 )

1 Cocoon with distinct anterodorsal projection .......................................................................... inthanonense

- Cocoon without distinct anterodorsal projection, although slight bulge may be present............................2

2 Terminal hooks with smooth outer margins.................................................................................................3

- Terminal hooks wider than high, with crenulated or serrated outer margins...............................................4

3 Gill ( Fig. 11 A) with stalk of dorsal triplet thinner than that of middle triplet ................................. asakoae

- Gill ( Fig. 11 I) with stalk of dorsal triplet as thick as that of middle triplet............................... nr. sheilae 3

4 Gill with angle formed by stalks of ventral pair and dorsal triplet more than 90 degrees when viewed later- ally ( Fig. 11 G) ...................................................................................................................... trangense n. sp.

- Gill ( Fig. 11 B–F, H) with angle formed by stalks of ventral pair and dorsal triplet 90 degrees or less when viewed laterally............................................................................................................................................5

5 Gill ( Fig. 11 D) with angle formed by stalks of ventral pair and dorsal triplet about 60 degrees when viewed laterally........................................................................................................................ nr. asakoae 3

- Gill ( Fig. 11 B, C, E, F, H) with angle formed by stalks of ventral pair and dorsal triplet about 90 degrees when viewed laterally..................................................................................................................................6

6 Anterodorsal margin of cocoon somewhat produced anteriorly...................................... doisaketense n. sp.

- Anterodorsal margin of cocoon not produced anteriorly.............................................................................7

7 Gill ( Fig. 11 B) with common basal stalk longer than stalk of middle triplet ........................ curtatum n. sp.

- Gill ( Fig. 11 C, E, F) with common basal stalk shorter than stalk of middle triplet.....................................8

8 Gill ( Fig. 11 F) with dorsal and middle groups composed of 1 individual and 2 paired filaments on stalk of moderate length ................................................................................................................................. sheilae

- Gill ( Fig. 11 C, E) with dorsal and middle groups composed of 3 filaments arising close together............9

9 Gill ( Fig. 11 C) with stalk of dorsal triplet thinner than that of middle triplet ......................... nr. asakoae 2

- Gill ( Fig. 11 E) with stalk of dorsal triplet as thick as that of middle triplet............................ nr. asakoae 4

Figures

FIGURE 11. Gill filaments of 10 cytoforms of the Simulium ceylonicum species group in Thailand. (A) S. asakoae, (B) S. curtatum n. sp., (C) S. nr. asakoae 2, (D) S. nr. asakoae 3, (E) S. nr. asakoae 4, (F) S. sheilae, (G) S. trangense n. sp., (H) S. doisaketense n. sp., (I) S. nr. sheilae 3, and (J) S. inthanonense. Scale bar = 0.1 mm.