Choroterpes Eaton, 1881

Selvakumar, C., Subramanian, K. A., Chandra, Kailash & Jehamalar, E. Eyarin, 2017, A new species of Choroterpes Eaton, 1881 (Ephemeroptera: Leptophlebiidae) from India, Zootaxa 4338 (1), pp. 189-194 : 193

Key to the known species of Choroterpes Eaton, 1881 in India (Larva)

1. Gills present on abdominal segments 2–7; maxillary and labial palp elongated and with long filtering setae ................................ 2

- Gills present on abdominal segments 1–7; maxillary and labial palp not as above ......................................................................... 3

2. Labrum with deep median emargination and sharp semicircular impression on the dorsal surface; maxilla with inner-apical angle produced as tusk-like process .......................................................................................... C. (Dilatognathus) nigella (Kang & Yang)

- Labrum with shallow median emargination and without sharp semicircular impression on the dorsal surface; maxilla with inner- apical angle not produced as tusk-like process .......................................... C. (Dilatognathus) nicobarensis Selvakumar & Chandra

3. Gills 2–7 monolamellate .............................................................. C. (Monochoroterpes) nandini Selvakumar & Sivaramakrishnan

- Gills 2–7 bilamellate ......................................................................................................................................................................... 4

4. Middle abdominal gills terminated in 3 processes with median projection longer than laterals... Choroterpes (Choroterpes) ........ 5

- Middle abdominal gills terminated in 3 slender subequal processes... Choroterpes (Euthraulus) .................................................... 6

5. Gill 1 single; upper and lower lamellae of gills 2–7 with 3 apical processes, median process relatively slender and longer than lat- erals ...................................................................................... C. (Choroterpes) kaegies Selvakumar, Subramanian & Chandra sp. n.

- Gill 1 double; upper and lower lamellae of gills 2–7 with 3 apical processes, median process relatively larger and longer than lat- erals .................................................................................................................................. C. (Choroterpes) petersi Tong & Dudgeon

6. Dorsal and ventral lamellae plate-like, narrow and terminating in three slender subequal processes, tracheae unbranched; antero- median emargination of labrum comparatively narrow and deeply cleft (‘V’ shaped)....................................................................... .............................................................................. C. (Euthraulus) nambiyarensis Selvakumar, Arunachalam & Sivaramakrishnan

- Dorsal and ventral lamellae plate-like, oval and terminating in three slender subequal processes, tracheae branched; anteromedian emargination of labrum deep (U-shaped) ............................... C. (Euthraulus) alagarensis Dinakaran, Balachandran & Anbalagan