Eotrechus elongatus Vitheepradit and Sites

Nakthong, La-Au, Vitheepradit, Akekawat & Sites, Robert W., 2014, Key to the species of Eotrechinae (Hemiptera: Heteroptera: Gerridae) of Thailand and review of the fauna of the Phetchabun Mountain Range, Zootaxa 3860 (1), pp. 47-63 : 59

Eotrechus elongatus Vitheepradit and Sites

Figs. 36 , 40

Eotrechus elongatus Vitheepradit and Sites 2007 : Zootaxa 8−12.

Diagnosis. Males of E. elongatus have an elongate pygophore with a blunt tip and a wide, angular notch on the posterior margin of abdominal sternum VIII ( Fig. 40 ). Males of this species have the mesosternum approximately twice as long as the metasternum, whereas in E. kalidasa the mesosternum is less than twice as long as the metasternum ( Andersen 1982b). Males have an elongate pygophore with a blunt tip, whereas those of E. romglao have a triangular pygophore with a small pair of lateral projections.

Discussion. This species is known only from Thailand ( Vitheepradit & Sites 2007). More specifically, specimens of E. elongatus were collected mainly on the rock surfaces at the sides of the waterfalls in Phu Hin Rongkla NP, which were occasionally splashed by water and covered by moss and vegetation ( Vitheepradit & Sites 2007). This species occurred syntopically with E. romglao at Romglao Waterfall in Phu Hin Rongkla NP ( Vitheepradit and Sites 2007). Several collections were conducted at the type locality and adjacent areas from 2010 to 2012; however, no additional specimens were found. This species is a local endemic in the area of Phu Hin Rongkla NP in Phitsanulok Province.

Material examined. THAILAND: Phitsanulok Province: Phu Hin Rongkla NP, Romglao Waterfall, 16°59'N 101°00'E, 1190 m, 22-IV-2002, CMU team (3 winged males, 1 winged female); same locality, 22-IV-2002, N. Changthong (1 winged male); same locality, 22-IV-2002, A. Nantakwang (1 winged male); same locality, 22-V- 2002, CMU team (13 winged males, 12 winged females); same locality, 21-VI-2002, CMU team (1 winged female); same locality, 23-VIII-2002, CMU team (1 wingless male, 2 winged males); same locality, 28-IX-2002, CMU team (1 winged male, 2 winged females); same locality, 21-X-2002, CMU team (1 winged male, 1 winged female); same locality, 15-XI-2002, CMU team (3 winged females); same locality, 15-XII-2002, CMU team (2 winged males, 2 winged females); same locality, 17-III-2003, CMU team (2 winged males, 1 winged female); same locality, 10-IV-2003, CMU team (7 winged males, 6 winged females); same locality, 4-V-2003, CMU team (2 winged males, 4 winged females); same locality, 11-III-2002, R.W. Sites, A. Vitheepradit, and K. Kirawanich, L- 288 (6 winged males, 3 winged females); same locality, 6-V-2003, A. Vitheepradit, T. Prommi, and M. Ferro, L- 507, (76 winged males, 37 winged females); Phu Hin Rongkla NP, Man Daeng Waterfall, tier 5, 16 °57'N 101° 03'E, 1250 m, 11-III-2002, G.W. Courtney, (1 winged male).

Figures

FIGURES 36 – 39. Forelegs of male Eotrechus. (36) E. elongatus, (37) E. petraeus, (38) E. romglao, (39) E. siamensi s.

FIGURES 40 – 45. Terminal abdominal segments of male Eotrechus. (40) E. elongatus, (41) E. hygropetricus, (42) E. kalidasa, (43) E. petraeus, (44) E. romglao, (45) E. siamensi s.