Archaeoptilomera derlethi, Zettel, 2009

Zettel, H., 2009, Three new genera of Ptilomerinae (Hemiptera: Heteroptera: Gerridae) from Southeast Asia, Zootaxa 2046 (1), pp. 26-42 : 40

Archaeoptilomera derlethi sp. n.

( Figs. 25 , 27–29, 31, 33 )

Holotype (apterous female). " Indonesie - Est Kalimantan \ Malinau bas., Seturan riv.\ Loc. Seturan (2000-bloc 45)\ 116°32'25" E, 03°00'09" N \ 29.06.2000. Derleth, P. (B0631)" (Kantonmuseum Lausanne).

Type locality. Indonesia, Borneo, East Kalimantan, Malinau Basin, Seturan River at Seturan , 116° 32' 25" E, 03° 00' 09" N. Collected in a medium-sized stream (4–6 m wide, 0.05–0.25 m deep) with moderate flow (0.7 m /s); stream morphology mainly running, cascade, and riffle; substratum composed of gravel, boulder, and cobble; in unlogged primary forest (Pascale Derleth, pers. comm.) .

Description of apterous female. Genus characteristics are not repeated here.

Dimensions. Body length 8.1 mm. Maximum body width at mesoacetabula 2.7 mm. Head width 1.38 mm. Length of second antennomere 0.99 mm. Length of mesofemur 11.0 mm.

Colour. Pronotum with thin lateral stripes. Metanotum with black mark above and separated from spiracle. Acetabula with large black marks distally; metacetabulum with black mark at base in addition.

Structural characteristics. Minimum distance of eyes 0.27 times head width. Relative lengths of antennomeres: 3.5: 1 (= 0.99 mm): 1.4: 0.9. Pronotum width 1.85 times median pronotum length. Lengths of leg segments relative to mesofemur: profemur 38, protibia 32, protarsus 9+6, mesofemur 100 (= 11.0 mm), mesotibia 59, mesotarsus 27+3, metafemur 102, metatibia 43, metatarsus 2. Profemur slender, length 9.5 times maximum width near base. Metafemur hardly longer than metafemur (1.02 times). Measured dorsally along midline, abdomen 1.05 times as long as thorax. Apex of abdomen comparatively high ( Fig. 29 ). All tergites distinctly wider than long; tergite 1 almost flat and with shiny area in centre; tergite 7 larger than others, medially 1.7 times as long as tergite 6. Connexival spines ( Figs. 29, 31 ) narrow and moderately long, slightly asymmetrical in the holotype (probably an artefact), not reaching convex hind margin of large tergite 8. Proctiger relatively small, elongate, with truncate hind margin. Gonocoxa plate-shaped except with distinct bend at posterior fourth, appearing angular in ventral view ( Fig. 33 ). Medial lobe of sternite 7 comparatively large ( Fig. 33 ), its ventral outline almost straight in lateral view ( Fig. 29 ).

Comparative notes. See A. kodadai sp. n.

Distribution. Borneo: East Kalimantan, only known from the type locality.

Etymology. The species is dedicated to Dr. Pascale Derleth (Lausanne, Switzerland) who collected the holotype. The epithet is a noun in the genitive case.

Figures

FIGURES 25–26. Archaeoptilomera gen. n. (25) Habitus of apterous female of A. derlethi sp. n. (holotype, body length 8.1 mm), dorsal aspect. (26) Habitus of apterous female of A. kodadai sp. n. (holotype, body length 8.5 mm), dorsal aspect. © NHMW Hemiptera Image Collection, published with permission.

FIGURES 27–34. Archaeoptilomera gen. n. (holotypes, females). (27) Head of pronotum of A. derlethi sp. n., dorsal aspect. (28) Foreleg of A. derlethi sp. n., posterior aspect. (29–34) Posterior part of abdomen in (29, 30) lateral, (31, 32) dorsal, and (33, 34) ventral aspects. (29, 31, 33) A. derlethi sp. n. (30, 32, 34) A. kodadai sp. n. gc1 = gonocoxa 1; pr = proctiger; s7 = sternite 7; t7, t8 = tergite 7, 8.