Enithares kasim, Polhemus, 2020

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 : 160

Enithares kasim new species

( Figs. 5 , 45, 46 , 52 , 67 )

Type material examined. Holotype, male (dissected): INDONESIA, Irian Jaya Prov. [Papua Prov.], New Guinea, pools in muddy lowland rain forest streambed, 28 km. NE of Kasim on pipeline road, 15 m., 2 October 1991, 01°15′17′′S, 131°14′11′′E, CL 2630, D. A. Polhemus and J. T. Polhemus ( BPBM) . Paratypes: INDONESIA, Irian Jaya Prov. [Papua Prov.]: 1 male, 5 females, same data as holotype CL 2630, D. A . Polhemus and J. T. Polhemus ( USNM, BPBM) .

Description. Male: Length 8.90 mm, width across pronotum 3.20 mm.

Coloration: Ground color dark brown ( Fig. 45 ). Vertex and frons creamy white, with diffuse brown centrally at anterior apex of frons. Pronotum with anterior half creamy white, posterior half dark brown. Scutellum dark brownish centrally, transitioning to yellowish-brown along lateral margins. Hemelytra hyaline, with clavus and corium bluish-grey, longitudinally suffused with black along claval suture, inner portion of corium bordering clavus, and along embolium, overall hemelytral coloration appearing darker due to dorsal abdominal color showing through; wing membrane dark fumate brown. Legs yellowish brown, fore and middle tibiae darkened distally, anterior edge of hind femur narrowly margined with dark brown. Venter brown, with coxal plates tan.

Structural characters: Head broadly rounded anteriorly when viewed dorsally. Head length 0.95; greatest width 2.55, equal to 0.79 pronotal width; anterior width of vertex 0.80, equal to 0.89× head length. Synthlipsis 0.50, about 0.62 anterior width of vertex and clearly shorter than pronotum. Pronotal length along midline 1.10, humeral width 3.20, lateral margins nearly straight, posterior margin weakly sinuate. Dorsal margin of pronotal fovea directed caudad behind eyes ( Fig. 45 ). Nodal furrow curved weakly cephalad, removed by 2.0× its length from membranal suture, length 0.50, distance to membranal suture 1.00.

Front and hind legs typical for genus, lacking unusual modifications. Middle trochanter angular. Middle femur with sharp subapical tooth bearing a sloping shoulder distally with 3 small, black, peg-like teeth. Lengths of leg segments as follows: fore femur–tibia–tarsal 1–tarsal 2 = 1.35/1.35/0.55/0.30; middle femur–tibia–tarsal 1–tarsal 2 = 2.00/1.70/0.60/0.40; hind femur–tibia–tarsal 1–tarsal 2 = 3.10/2.70/1.10/0.80.

Ventral abdomen with metaxyphus triangular, slightly concave, tip acuminate ( Fig. 5 ).

Male genitalia when viewed laterally ( Fig. 52 ) with proctiger angular; pygophore with posteroventral angle forming nearly a right angle bearing a prominent setal tuft, posterior lobe broadly curved along posterior margin, dorsal margin truncate, angled slightly anterad; paramere small, crescent-shaped, reaching only halfway to apex of posterior lobe; lateral arm of basal plate broadly expanded distally, dorsal apex nearly straight; aedeagus semicircular, with numerous transverse folds.

Female: Length 8.0 mm., width across pronotum 3.20 mm. Similar to male in general structure and coloration, with following exceptions: general coloration yellowish-brown ( Fig. 46 ); upper frons with a pair (1+1) of prominent, longitudinally ovate reddish spots to either side of midline.

Etymology. The name “kasim” is a noun in apposition, and refers to the type locality at Kasim, near the furthest western point on the island of New Guinea.

Discussion. Enithares kasim is similar in certain respects to E. megalops , but is slightly larger and stouter in overall form. The male genitalia will also readily separate the two species. The paramere of E. megalops is nearly vestigial, being represented by a small, rounded nub, whereas the paramere of E. kasim is somewhat larger, more obvious, and crescent-shaped (compare Figs. 49, 52 ). The PL of E. megalops takes the form of a broadly rounded triangle, whereas that of E. kasim it is bent anteriorly, with a truncate apex (compare Figs. 49, 52 ). Finally, the LABP of E. megalops is gently curved and slightly tapering, with a blunt apex, whereas the LABP in E. kasim is broadly expanded distally, with a relatively straight dorsal margin leading to a broadly rounded apex (compare Figs. 49, 52 ). The mesotrochanter of E. kasim is also more angular than that of E. megalops .

Ecological notes. E. kasim is presently known only from the extreme western portion of the Vogelkop Peninsula ( Fig. 67 ), occupying the Vogelkop Lowlands area of freshwater endemism (Areas 4) as defined by D. Polhemus & Allen (2007). The type locality was a shaded streambed in lowland swamp forest, with scattered pools connected by hyporheic flow. Collections were made in the dry season, when the water is low and aquatic biota concentrates in such remnant pools; during the wet season the channel would be filled, representing a continuous and far more extensive habitat.

Figures

FIGURE 67. Distribution of species in the E. megalops group on New Guinea. Square = E. kasim n. sp.; circles = E. nigra Lansbury; triangles = E. alexis Lansbury; pentagons = E. vulgaris Lansbury.

FIGURES 2–7. Enithares species, metaxiphus. 2. E. arfak n. sp.; specimen from Indonesia, West Papua Prov., Mupi River, CL 2646. 3. E. bosavi n. sp.; holotype specimen from Papua New Guinea, Southern Highlands Prov., Mt. Bosavi, CL 7206. 4. E. insularis n. sp.; specimen from Papua New Guinea, Milne Bay Prov., Fergusson Island, CL 7181. 5. E. kasim n. sp.; specimen from Indonesia, West Papua Prov., Kasim, CL 2630. 6. E. orsaki n. sp.; specimen from Papua New Guinea, Madang Prov., Reinduk, CL 7036. 7. E. papua n. sp.; specimen from Papua New Guinea, Central Prov., Tekadu, CL 7157.

FIGURES 41–48. Enithares species in the E. megalops group, dorsal habitus photographs. 41–42. Enithares megalops Lansbury, male and female; male specimen from Indonesia, West Papua Province, Kasim, CL 2620, female paratype specimen from Indonesia, West Papua Prov., Bomberai Peninsula. 43–44. Enithares paramegalops Lansbury, male and female; male specimen from Papua New Guinea, Gulf Province, Kopi, CL 7000, female paratype specimen from Indonesia, Papua Prov., Enarotali. 45–46. Enithares kasim n. sp., male and female; specimens from Indonesia, West Papua Province, Kasim, CL 2630. 47–48. Enithares arfak n. sp., male and female; specimens from Indonesia, West Papua Province, Mupi River, CL 2646.

FIGURES 49–54. Enithares species in the E. megalops group, male genitalic complex, left lateral view. 49. Enithares megalops Lansbury; specimen from Indonesia, West Papua Prov., Kasim, CL 2620. 50. Enithares paramegalops Lansbury; specimen from Papua New Guinea, Gulf Prov., Kopi, CL 7000, 51. Enithares arfak n. sp.; specimen from Indonesia, West Papua Prov., Mupi River, CL 2646. 52. Enithares kasim n. sp.; specimen from Indonesia, West Papua Prov., Kasim, CL 2630. 53. Enithares nigra Lansbury, specimen from Papua New Guinea, Southern Highlands Prov., Moro, CL 7024. 54. Enithares vulgaris Lansbury n. sp.; specimen from Indonesia, Papua Prov., Biak Island, CL 2643.