Platycnemididae

Keetapithchayakul, Tosaphol Saetung, Makbun, Noppadon, Phan, Quoc Toan, Danaisawadi, Patchara & Wongkamhaeng, Koraon, 2022, Description of the larva of Indocnemis orang (Förster in Laidlaw, 1907) (Odonata Platycnemididae: Calicnemiinae) from Thailand, with larval key to the known genera of the family Platycnemididae in Asia, Zootaxa 5134 (4), pp. 504-520 : 518

Taxonomic key to the known larvae of genera of family Platycnemididae in Asia

The larval comparison was based mainly on Orr & Dow (2015b) supplemented with Fraser (1943); Lieftinck (1953); Eda (1965); Ishida (1996); Xu (2013); Orr & Dow (2016); Chen & Yu (2020); Saetung et al. (2020); Xu (2021).

1 Labium with one pair of premental setae................................................................... 2

1’ Labium with more than one pair of premental setae.......................................................... 6

2 Palpal setae with same length; vertical lamella caudal gills.................................................... 3

2’ Palpal setae with different length; triquetro - quadrate caudal gills ( Fig. 13A ), triradiate in transverse section.... Calicnemia

3 2–4 palpal setae; weakly and moderately produced ligula; caudal gills with or without petiole......................... 4

3’ 6 palpal setae; strongly produced ligula; foliate caudal gills with distinct petiole ( Fig. 13G ).................. Onychargia

4 3–4 palpal setae; moderately produced ligula; denodate or subnodate vertical lamella caudal gills..................... 5

4’ 2 palpal setae; weakly produced ligula ( Fig. 12D ); nodate vertical lamella caudal gills, oblong shaped ( Fig. 13C )..... Nososticta

5 3 palpal setae; subnodate vertical lamella caudal gills, broad ovate shaped, with nodus on middle and distal thirds ( Fig. 13F )............................................................................................. Caconeura

5’ 3–4 palpal setae; denodate vertical lamella caudal gills, ovate shaped, without nodus ( Fig. 13K )............. Prodasineura

6 Labium with 2 pairs of premental setae.................................................................... 7

6’ Labium with more than 2 pairs of premental setae........................................................... 9

7 3–4 palpal setae; denodate vertical lamella caudal gills........................................................ 8

7’ 4 palpal setae; subnodate vertical lamella caudal gills ( Fig. 13I ) with fimbriated shape.......................... Copera

8 3 palpal setae; moderately produced ligula ( Fig. 12G ); presence of protuberance on occipital margin; body shorter than 1.3 x length of caudal gills........................................................................ Pseudocopera

8’ 3–4 palpal setae; strongly produced ligula ( Fig. 12I ); absence of protuberance on occipital margin; body longer than 1.5 x length of caudal gills......................................................................... Platycnemis

9 3–6 pairs of premental setae; 4–9 palpal setae; subdonate vertical lamella caudal gills.............................. 10

9’ 4 pairs of premental setae; 6–7 palpal setae; triquetro - quadrate type caudal gills ( Fig. 13B ), triradiate in transverse section.......................................................................................... Disparoneura

10 3–4 pairs of premental setae, 4–6 palpal setae; foliate to ovate caudal gills, with or without petiole ( Figs. 13D, 13J ) Coeliccia

10’ 5–6 pairs of premental setae, 8–9 palpal setae; ovate caudal gills, without petiole ( Fig. 13H )................ Indocnemis

Figures

FIGURE 12. Schematic contour of ligula (median lobe of prementum) of Asian representative Platycnemididae larvae: (A), poorly produced ligula; (B), moderately produced ligula; (C), strongly produced ligula; (D), Nososticta moluccensis redrawn from Lieftinck (1953); (E), Prodasineura autumnalis redrawn from Lieftinck (1953); (F), Copera chantaburii redrawn from Saetung et al. (2020); (G), Pseudocopera ciliata redrawn from Saetung et al. (2020); (H), Caconeura gomphoides redrawn from Fraser (1943); (I), Platycnemis echigoana redrawn from Eda (1965); (J), Onychargia atrocyana redrawn from Orr & Dow (2015b); (K), Calicnemia gulinensis redrawn from Chen & Yu (2020); (L), Coeliccia flavostriata redrawn from Orr & Dow (2016); (M), Disparoneura apicalis redrawn from Fraser (1943); (N), Indocnemis orang, this study.

FIGURE 13. Drawing of median gill of larva of representatives of Asian Platycnemididae: (A), Calicnemia gulinensis,redrawn from Chen & Yu (2020); (B), Disparoneura apicalis, dorsal view, redrawn from Fraser (1943); (C), Nososticta moluccensis, redrawn from Lieftinck (1953); (D), Coeliccia flavostriata, redrawn from Orr & Dow (2016); (E), Coeliccia campioni, redrawn from Orr & Dow (2016); (F), Caconeura gomphoides, redrawn from Fraser (1943); (G), Onychargia atrocyana, redrawn from Orr & Dow (2015b); (H), Indocnemis orang, this study; (I), Copera chantaburii, redrawn from Saetung et al. (2020); (J), Coeliccia cyanomelas, redrawn from Xu (2013); (K), Prodasineura autumnalis, redrawn from Lieftinck (1953); (L), Platycnemis echigoana redrawn from Ishida (1996); (M), Pseudocopera ciliata redrawn from Saetung et al. (2020). Arrows indicate nodus of caudal gills.