Fontidessus bettae Miller & Montano

Miller, Kelly B. & Montano, Elizabeth T., 2014, Review of the genus Fontidessus Miller & Spangler, 2008 (Coleoptera, Dytiscidae, Hydroporinae, Bidessini) with description of four new species, ZooKeys 426, pp. 65-85 : 71-72

Taxon classification Animalia Coleoptera Dytiscidae

Fontidessus bettae Miller & Montano sp. n. Figs 3, 12, 19, 26, 31, 35

Type locality.

Venezuela, Bolivar State, Gran Sabana, E Pauji, Salto Catedral, 4°31'19.1"N, 61°31'34.0"W.

Diagnosis.

Fontidessus bettae is small (TL = 1.4 mm), but larger than all species except Fontidessus toboganensis , Fontidessus aquarupe , and Fontidessus microphthalmus , which are comparable in size (Figs 1-5). The dorsal maculae are distinctive. The elytron has a transverse, well-demarcated yellow macula near the anterior margin and a smaller, subapical yellow macula (Fig. 3). The anterior macula does not have medial or lateral posterior extensions along the disc (Fig. 3) as is often the case in Fontidessus tambopaticus (Fig. 5). The eyes in Fontidessus bettae are larger (Fig. 3, HW/EW = 1.5-1.6) than in Fontidessus microphthalmus (Fig. 1, HW/EW = 1.4-1.5). The male median lobe terminates in a narrow, pointed apex with only small lateral hyaline lobes (Fig. 26).

Description.

Measurements. TL = 1.4-1.5 mm, GW = 0.9 mm, PW = 0.7 mm, HW = 0.4-0.5 mm, EW = 0.3 mm, TL/GW = 1.7-1.8, HW/EW = 1.5-1.6. Body (Fig. 3) broadly oval; lateral outline nearly continuous between pronotum and elytron; lateral margins of pronotum gently curved; lateral margins of elytron evenly and gently curved.

Coloration. Head brown, pronotum dark brown along anterior and posterior margins with prominent yellow transverse region near anterior margin, darker yellow brown medially (Fig. 3); elytron brown with distinct, well-defined, yellow, transverse but slightly oblique macula near base and yellow triangular shaped macula near apex (Fig. 3). Ventral surfaces of thorax and abdomen dark brown to black 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 distinct microsculpture in the form of small cells; eyes medium in size (Fig. 3, HW/EW = 1.5-1.6). Pronotal surface similar to that of head; with posterior angles obtuse; lateral bead narrow, of even width throughout; pronotal striae finely incised, extending nearly 1/2 distance across pronotum (Fig. 3). Elytron with anterolateral angle obtuse, not extended anteriorly (Fig. 3); surface similar to pronotum. Prosternal process moderately broad, lateral margins evenly curved, apex of process narrowly rounded (Fig. 12); metacoxae impunctate, but with distinct microreticulation; metacoxal process with lateral lobe minute. Pro- and mesotarsi relatively narrow in both male and female, but slightly broader in male. Metatrochanter very large in relation to metafemur (Fig. 19).

Male genitalia. Median lobe in dorsal aspect broad basally, with lateral margins approximately evenly tapered to extremely slender, bifid apex, with small, but distinctive, hyaline lobes laterally (Fig. 26A); in lateral aspect moderately broad basally, apical portion moderately straight, lateral margins evenly tapered to extremely slender apex (Fig. 26C); with broad, rounded dorsal sclerite (Fig. 26B). Lateral lobe in lateral aspect broad basally, apical segment slender and moderately straight (Figs 26D).

Variation.

There is some minor variation in the extent and distinctiveness of the dorsal maculae, but relatively little variation among the few specimens examined.

Etymology.

This species is named to honor the second author’s grandmother, Elizabeth (Betty) Baca, who deeply inspired her to live well and seek knowledge.

Distribution and habitat.

Fontidessus bettae is known only from the type series in the Gran Sabana of Venezuela (Fig. 31). It was collected from "waterfall seeps", a hygropetric habitat along the margin of a waterfall (Fig. 35).

Material examined.

Holotype in MIZA: male labeled, "VENEZUELA: Bolivar State 4°31'19.1"N, 61°31'34.0"W, 860 m Gran Sabana, E Pauji. Salto Catedral 16.vii.2010 leg. Short & Tellez waterfall seeps; VZ10 –0716– 03B/ HOLOTYPE: Fontidessus bettae Miller & Montano, 2014 [red label with black line border]". Paratypes: 19 labeled same as holotype except “… /PARATYPE: Fontidessus bettae Miller & Montano, 2014 [blue label with black line border]".