Enithares elongata Lansbury, 1974

Polhemus, Dan A., 2020, Nine new species of Enithares (Heteroptera: Notonectidae) from New Guinea, with distributional notes on other species and an updated world checklist, Zootaxa 4772 (1), pp. 132-182 : 153

Enithares elongata Lansbury

( Figs. 23, 24 , 35 , 55 )

Enithares elongata Lansbury 1974: 226 .

Material examined. INDONESIA, Irian Jaya Prov. [= Papua Prov.], New Guinea: 7 males, 11 females, 1 im- mature, Cyclops Mountains, rocky stream above Pos Tujuh , NW of Sentani, 260– 300 m., 2°32′26′′S, 140°30′47′′E, water temp. 22.5 °C., 18 September 2000, 14:00–16:30 hrs., CL 7145, D. A . Polhemus ( USNM, BPBM); 1 male, 2 females, small rocky stream above Sentani, Cyclops Mountains , 335 m., [vic. 2°32′29′′S, 140°30′43′′E], water temp. 22° C., 25 September 1991, CL 2618, D. A . Polhemus and J. T. Polhemus ( BPBM); 12 males, 6 females, Logari River and tributaries at PTFI Landing Site 21, 290 m., 3°00′21′′S, 136°33′20′′E, water temp. 24° C. (main river), 7 April 1998, 09:00–14:00 hrs., and 8 April 1998, 09:00–12:00 hrs., CL 7092, D. A . Polhemus ( USNM, BPBM); 13 males, 8 females, Upper Ziwa River at PTFI Wapoga Alpha drilling camp, 1050 m., 3°08′41′′S, 136°34′25′′E, water temp. 19° C., 19 April 1998, 08:00–12:00 hrs., CL 7101, D. A . Polhemus ( USNM, BPBM); 1 male, 2 females, rocky rainforest tributary to upper Ziwa River at PTFI Wapoga Alpha drilling camp, 1050 m., 3°08′41′′S, 136°34′25′′E, water temp. 20° C., 18 April 1998, 10:00–17:00 hrs., and 19 April 1998, 14:00–18:00 hrs., CL 7100, D. A . Polhemus ( USNM, BPBM) . PAPUA NEW GUINEA, Morobe Prov.: 1 male, Wareo [Huon Peninsula], Rev. L. Wagner , S. A . Museum specimen [probably collected in 1929] ( BPBM) .

Discussion. This species was described in supplemental paper ( Lansbury 1974) that appeared after Lansbury’s (1968) monograph, and occurs in north-central New Guinea, to the north of the island’s central east-west drainage divide. The very elongate, vertically oriented male paramere is diagnostic, as are the posteriorly expanded arms of the basal plate ( Fig. 35 ).

This is the species treated in part under the concept of “ Enithares sp. undet #2′′ by D. Polhemus (2000) from sampling stations 41, 44, 47, 48, 56 and 57 in the Conservation International rapid assessment report covering surveys in the Wapoga River Basin of northern Indonesian New Guinea. The series taken from stations 41, 44, 47, 48 and 57 represented only E. elongata , while those from station 56 subsequently proved to be a mixed series containing both E. elongata and E. ziwa n. sp.

Ecological notes. Enithares elongata was abundant above Pos Tujuh (CL 7145) in the Cyclops Mountains of northern Indonesian New Guinea, occurring in pools along a very clear, steeply dropping stream occupying a mostly unshaded bed of very large boulders; this locality lay about 20 minutes walk above the World Wildlife Fund’s research station. At the Wapoga Alpha geological exploration camp of the P. T. Freeport Indonesia Corporation in the central mountains of Indonesian New Guinea (CL 7100), E. elongata was taken from a set of pools in muddy substrate below a seeping rock face, formed where a small streamlet passed across a bedrock outcrop. These pools lay immediately behind the camp, in the valley of the upper Ziwa River.

Enithares elongata occurs sporadically across a broad geographic range in drainages north of New Guinea’s central east-west drainage divide ( Fig 55 ), and occupies at least three of the areas of New Guinea freshwater endemism defined by D. Polhemus & Allen (2007): the Cyclops Mountains (Area 12), the West Papuan Central Highlands (Area 20), and the Adelbert, Finisterre and Saruwaged Mountains (Area 14).

The original type series of E. elongata was taken by Cheesman from “Mt. Nomo, S. of Bougainville, 700 ft. ”; this locality lies east of the Tami River and southwest of Mt. Bougainville at approximately 2°42′06′′S, 140°56′26′′E. The Logari River and Ziwa River records from the Wapoga River basin represent a significant westward range extension, and indicate that this species may occur in the hill country along the entire northern and southern flanks of the Mamberamo River basin. The specimen from Wareo comes from the far eastern tip of the Huon Peninsula, and similarly represents a significant eastward range extension into the part of the island generally occupied by E. atra (see discussion under that species). This latter record appears valid, however, given that the specimen was taken by the Reverend L. Wagner, who made collections in the vicinity of various Lutheran mission stations on the Huon Peninsula in 1929. His material went to the South Australian Museum, and the specimen in question has a red label attached indicating that it was formerly in that institution.

Figures

FIGURE 55. Distribution of species in the E. atra group on New Guinea. Square = E. digitata Lansbury; circles = E. elongata Lansbury; triangles = E. insularis n. sp.; pentagon = E. tagula n. sp.

FIGURES 23–29. Enithares species in the E. atra group, dorsal habitus photographs. 23–24. Enithares elongata Lansbury, male and female; specimens from Indonesia, Papua Province, Cyclops Mountains, CL 7145. 25–26. Enithares papua n. sp., male and female; specimens from Papua New Guinea, Southern Highlands Prov., male specimen from Swinging Bridge, CL 7020, female specimen from Tubage, CL 7022. 27. Enithares ziwa n. sp., male holotype, specimen from Indonesia, Papua Province, upper Ziwa River, CL 7100. 28–29. Enithares stylata Lansbury, male and female; specimens from Papua New Guinea, Western Highlands Prov., near Mt. Hagen, CL 1780.

FIGURES 35–40. Enithares species in the E. atra and E. bakeri groups, male genitalic complex, left lateral view. 35. Enithares elongata Lansbury; specimen from Papua New Guinea, Morobe Prov., Wareo. 36. Enithares ziwa n. sp.; specimen from Indonesia, Papua Prov., Ziwa River, CL 7100. 37. Enithares stylata Lansbury; specimen from Papua New Guinea, Morobe Prov., Wau, CL 1817. 38. Enithares tagula n. sp.; specimen from Papua New Guinea, Milne Bay Prov. Tagula Is., CL 7190. 39. Enithares bakeri Brooks, specimen from Indonesia, West Papua Prov., Aimasi River, CL 2651. 40. Enithares loria Brooks; specimen from Indonesia, Papua Prov., Siewa, CL 7085.