Agriocnemis pygmaea ( Rambur, 1842 ), 1877

Saetung, Tosaphol & Boonsoong, Boonsatien, 2019, A review of genus Agriocnemis larva (Odonata: Coenagrionidae) from Thailand including a description of the final stadium larva of Agriocnemis minima Selys, 1877 with supporting molecular (COI) data, Zootaxa 4711 (3), pp. 579-599 : 585-586

Agriocnemis pygmaea ( Rambur, 1842)

Figs. 1, 4, 7 , 37 , 45 , 47 , 54 , 60 , 63, 65 , 67, 69 , 72–73

Agrion pygmaeum Rambur (1842) : 278 [Holotype female, lost]

Agriocnemis australis Selys (1877) : 155 [original description]

Agriocnemis velaris Hagen in Selys (1882) : 31 [original description]

Agriocnemis hyacinthus Tillyard 1913: 457 [original description]

Agriocnemis pygmaea Selys (1877) : 146; Fraser (1933): 398, figs. 163, 171 [adult description]; Kumar (1973): 93, figs. 103–113 [larval description]; Ishida (1996): 192, figs. 31, 268, 471, 852, 945 [larval description]; Orr (2005): 38

Specimens examined. THAILAND: 2 reared specimens; 1 ♂ and 1 ♀, 12/III/2017, Kasetsart University (13°50′59″ N 100°34′26″ E, altitude 4.48 m), Bangkok province, T. Saetung leg. 4 last stadium larvae; 1 ♂ and 1 ♀ 6/X/2018, Ban Na district (14°16′41′′ N, 101°00′57′′ E, altitude 8.6 m), Nakhon Nayok province, T. Saetung & B. Boonsoong leg.

Diagnosis. The larvae of A. pygmaea can be distinguished from known species based on the following combination of characteristics: 1) occiput with numerous dark spots; each spot bears a spiniform seta on dorsal view ( Fig. 63 ); 2) pronotum with protrusion on the posterolateral side, forming a rounded shape ( Fig. 65 ); 3) margin of compound eyes with a row of numerous spiniform setae on the ventral view ( Fig. 67 ); and 4) S3–S4 covered with long simple setae ( Fig. 69 ).

Figures

FIGURE 37. Bayesian analysis tree based on COI of Agriocnemis spp. Values of Bayesian posterior probabilities are indicated at nodes (L = larva, m# = male adult).

FIGURES 1–9. Diagnosis character for identified adults of genus Agriocnemis (1–9): (1, 4, 7) A. pygmaea; (2, 5, 8) A. femina femina; (3, 6, 9) A. minima: (1–3) lateral view of male caudal appendages; (4–5) lateral view of female prothorax; (7–9) dorsal view of female prothorax. Scale = 0.5 mm.

FIGURES 42–45. Adults of Agriocnemis spp. (42–45): (42) A. minima, male; (43) A. minima, female; (44) A. femina femina, male; (45) A. pygmaea, male. (arrow = distinctive mark)

FIGURES 46–48. Caudal gills of Agriocnemis spp. (46–48): (46) A. minima, (47) A. pygmaea; (48) A. femina femina; (46a, 47a, 48a) median gill, (46b, 47b, 48b) lateral gill. Scale = 0.5 mm.

FIGURES 52–56. Antenna of Agriocnemis spp. (52–56): (52) A. corbeti (redrawn from Kumar & Prasad (1978)); (53) A. lacteola (redrawn from Chowdhury & Miah (1990)); (54) A. pygmaea; (55) A. femina femina; (56) A. minima. Scale = 0.2 mm.

FIGURES 57–61. Distal margin of labial palp of Agriocnemis spp. (57–61): (57) A. corbeti (redrawn from Kumar & Prasad (1978)); (58) A. lacteola (redrawn from Chowdhury & Miah (1990)); (59) A. femina femina; (60) A. pygmaea; (61) A. minima. Scale = 0.2 mm.

FIGURES 62–65. Larva of Agriocnemis spp. (62–65): (62, 64) A. femina femina, (63, 65) A. pygmaea: (62–63) dark spots on head, dorsal view, (64–65) prothorax, dorsal view. Scale = 0.4 mm.

FIGURES 66–69. Larva of Agriocnemis spp. (66–69): (66, 68) A. femina femina, (67, 69) A. pygmaea; (66–67) row of spiniform setae on margin of compound eyes, ventral view, (68–69) setae on abdominal S3–S4 (arrow). Scale = 0.2 mm.

FIGURES 70–75.Adults of Agriocnemis spp. (70–75): (70–71) A. femina femina, (72–73) A. pygmaea; (74–75) A. minima; (70, 72, 74) ventral view of genital ligula, (71, 73, 75) lateral view of genital ligula. Scale = 0.1 mm. (T = teeth on distal of genital ligula segment 2, L = lateral lobe)