Fontidessus ornatus K. B. Miller ex K. B. Miller & Spangler 2008

Fontidessus ornatus adolah kumbang dari famili Dytiscidae. Spesies ko juo marupokan bagian dari ordo Coleoptera, kelas Insecta, filum Arthropoda, dan kingdom Animalia.

Measurements. TL = 1.1–1.2 mm, GW = 0.6–0.7 mm, PW = 0.6–0.7 mm, HW = 0.4–0.5 mm, EW = 0.1–0.2 mm, TL/GW = 1.8–1.9, HW/EW = 1.5–1.6. Body (Figs 7, 8) oval, elongate; lateral outline slightly continuous between pronotum and elytron; lateral margins of pronotum gently curved; lateral margins of elytron evenly and gently curved. Coloration. Head yellow brown, darker in region near medial margins of eyes; pronotum yellow brown, diffusely brown medially along posterior margin and in narrow band along anterior margin; elytron brown with diffuse yellow pattern, yellow basally, laterally along about ¾ length of elytra and in subtriangular subapical area (Fig. 8). Other specimens much darker, with elytral maculae reduced overall (Fig. 7). Ventral surfaces of thorax and abdomen brown except prosternum, prosternal process, propleuron and pronotal epipleuron yellow-brown; appendages yellow to yellow-brown. Sculpture and structure. Head with very fine, inconspicuous, irregular punctation, surface between punctures shiny with indistinct microsculpture in the form of small cells; eyes medium in size (Figs 7, 8, HW/EW = 1.5–1.6). Pronotal surface similar to that of head; with posterior angles obtuse; lateral bead slender, of even width throughout; pronotal striae finely incised, extending nearly 1/2 distance across pronotum (Figs 7, 8). Elytron with anterolateral angle obtuse, not extended anteriorly (Figs 7, 8); surface similar to pronotum but with microsculpture more indistinct. Prosternal process relatively narrow, lateral margins tapered to narrowly rounded apex (Fig. 15); metacoxal process with lateral lobe minute. Pro- and mesotarsi relatively narrow in both male and female. Metatrochanter very large relative to metafemur (Fig. 22). Male genitalia. Median lobe in dorsal aspect complex, apically terminating in two elongate, narrow rami with medial deep, narrow emargination, laterally with broad, hyaline lobes (Fig. 29A); in lateral aspect narrow, straight, apically with distinct subapical hyaline lobe and apex slightly bent, apically very slender (Fig. 29C); ventral sclerite short, broad, apically rounded (Fig. 29B). Lateral lobe slender medially, apically expanded and broadly rounded (Fig. 29D).

Fontidessus ornatus is more widespread and common than other species in the genus. It ranges from the western margin of the Guiana Shield through northeastern Venezuela to central and southern Suriname (Fig. 33). It is found in hygropetric habitats.