Naucoris sumatranus Fieber, 1851

Zettel, Herbert, 2011, The type of the enigmatic creeping water bug Naucoris sumatranus FIEBER, 1851 (Hemiptera: Heteroptera: Naucoridae), Zootaxa 2981, pp. 65-68 : 65-67

Naucoris sumatranus Fieber, 1851

( Figs. 1–8 )

Naucoris sumatrana Fieber, 1851: 17 (description; type locality: Sumatra), pl. I (figs. E 11, 12). Naucoris sumatranus: Lundblad 1933: 63 (listed).

Naucoris sumatranus: Chen et al. 2005: 419 (listed).

Type material. Lectotype (by present designation; see discussion), macropterous female, Natural History Museum Vienna. Specimen see Figs. 1–3, 6–8 ; labels see Fig. 4 . The female lectotype is pinned and in reasonably good condition. The right forewing (except clavus) was broken off (probably during pinning) and glued to the body; the apical part of its clavus and small marginal parts of the membrane are missing. Antennae and legs are complete, except for the right hind leg which is broken off at the femur. The abdominal venter is dirty and the standing pilosity is only partly visible.

Original description. Fieber's (1851) description is extremly short. It reads: " Naucoris Sumatrana mihi Fig. 11. auct. Fig. 12 pes ant.) Lutescens, capite lituris quatuor, thoraceque maculis duabus trapezoidalibus fuscopunctatis. Scutellum nigrum. Hemelytra fusca, subtilissime albo-granulata. Embolium margine lutescente. Dorsum nigrum. Long. 3½ – 3 2/3 lin. Habitat in insula Sumatra. (Mus. Caes. Vindob.)" The figures depict the dorsal habitus and the foreleg ( Fig. 5 ).

Redescription of lectotype. Size: body length 8.06 mm; maximum body width (at embolar margin) 4.94 mm; head width across eyes 2.99 mm; pronotal width 4.20 mm.

Colour (dorsum see Fig. 1 ; venter see Figs. 2, 3 ): Head and pronotum yellow, both with areas covered with small brownish dots forming markings: on head with longitudinal stripes at posterior two-thirds, on pronotum with pair of large trapezoidal areas on disk; in addition, pronotum anteriomedially with light brown solid mark. Mesoscutellum black; mesoscutum (its posterior margin visible due to a slightly bent pronotum) with three large black marks separated by yellow areas. Hemielytron light brown, densely beset with small whitish granules; yellow patch on embolium indistinctly limited. Connexiva dorsally and ventrally yellow; tergites blackish. On venter, head and prothorax yellowish brown; remaining parts dark brown. Labrum, rostrum, antennae, and legs yellowish. Subgenital plate pale yellow in distal half.

Structures: Head dorsally shiny, with reticulation; meshes anteriorly large and obliterated; width across eyes 2.2 times head length, synthlipsis 0.7 times head width across eyes; head ventrally carinate; head margin at postero-lateral eye margin hardly recognizable. Labrum inserted at anterior margin of head, length 0.65 times width; ventral extension of maxillary plate 0.65 times length of labrum. Rostral cavity circular; rostral segments 3 and 4 of same length at anterior margin, segment 4 posteriorly with two tufts of hairs close to apex, segment 3 ventro-apically bare.

Pronotum ( Fig. 1 ) evenly, but weakly convex, subtrapezoidal, with weakly curved lateral margins, which slightly more convergent anteriad; maximum width close to posterior corners 2.1 times larger than median length. Pronotum moderately shiny, sculpture in four areas differently developed: transversely wrinkled along midline (posteriorly tending to form transverse meshes); disk (area with dark punctures) reticulate, with isodiametric to slightly transverse meshes, similar to but slightly more distinct than on head, and meshes with small central foveae; posterior part reticulate, with very fine, longitudinal meshes; lateral parts very finely vermiculate. Mesoscutellum 2.1 times wider than long, weakly shiny, punctate and wrinkled, with many small granules. Hemielytron with well separated embolium and clavus, clavus longitudinally divided by a suture (macropterous condition); entire hemielytron densely beset with small granules; clavus, corium, and embolium matt, very finely rugose, coriaceous; membrane slightly shiny, with reduced sculpture except for granules. Prosternum carinate. Mesosternum with anterior notch, posteriorly with high median carina. Metaxiphus ( Fig. 7 ) short and high, as high as mesosternal carina, apex narrowly rounded, posterior margin almost straight.

Profemur ( Figs. 2, 6 ) largely expanded, also on flexor side, maximum width 0.7 times maximum length; protibia evenly curved, protarsus separated from protibia, but immovably fused; claw reduced. Mesotibia at flexor side with two rows of suberect, short and long spines over entire length; metatibia at flexor side also with two rows, the ventral (anterior) one over entire length, the dorsal (posterior) one restricted to distal half; claws of hind leg 0.5 times as long as segment 3 of metatarsus.

In dorsal aspect, abdomen posterolaterally clearly surpassing hemielytra; posterior corners of connexiva 2–4 subrectangular, 5–6 with minute spine. Venter of abdomen symmetrical, with dense pilosity, standing setae mostly in middle (on other parts possible rubbed of or attachted to surface because of dirt). Subgenital plate (sternum 7; Fig. 8 ) comparatively short, distally moderately tapered, hind margin broadly rounded, but medially with very gentle emargination.

Figures

FIGURES 1 – 10. 1 – 8 Naucoris sumatranus, lectotype, female. 9, 10 Naucoris obscuripennis, female from Luzon, the Philippines (Natural History Museum Vienna). 1 Habitus, dorsal aspect. 2 Head, prothorax and forelegs, ventral aspect. 3 Abdomen, ventral aspect). 4 Labels. 5 Part of plate I from Fieber (1851); figs. 11 and 12 refer to N. sumatranus. 6 Right foreleg, ventral aspect. 7, 9 Metaxiphus, lateral (left) aspect. 8, 10 Subgenital plate (sternum 7) of female, ventral aspect. (Figs. 1 – 4: © NHMW Hemiptera Image Collection, published with permission.)