Pspehenops bifidus, Novelo-Gutiérrez, 2017

Novelo-Gutiérrez, Rodolfo, 2017, Two new species of Psephenops Grouvelle (Coleoptera: Byrrhoidea: Psephenidae) from Panama, Zootaxa 4323 (1), pp. 109-118 : 110-113

Pspehenops bifidus sp. nov.

( Figs 1–8 )

Type material. Holotype male labeled: PANAMA: Province of Panama; Chame District , Río Marías, 325 m a.s.l., (08°38.020’ N, 80°01.510’ W), 26 April 2015, R. Novelo leg. ( IEXA) . Paratypes, 5 m #, same data as holotype ( IEXA).

Description. Holotype Male: Total length, 2.95 mm; humeral width, 1.10 mm. Body oval, depressed; integument reddish-brown, head and pronotum black; elytra dark reddish-brown completely covered with yellow short setae with golden reflections, and dark red long setae ( Fig. 1 ); trochanters and basal 2/3 of femora light yellow, distal 1/3 reddish-brown; tibia and tarsi reddish-brown; venter reddish-brown, vestiture short, fine and dense, whitish with yellow reflections ( Fig. 2 ).

Head: Short, transverse; clypeus subrectangular, declivous at an angle of less than 90 degrees from the plane of the frons, distal margin widely emarginated; fronto-clypeal surface and vertex with short yellow setae and long, dark red setae, vertex minutely punctate. Antennae short (e.g. when fully extended backwards, not reaching posterior margin of pronotum), moniliform, 11-segmented; scape longest; pedicel subglobose, half as long as scape; third antennomere subtriangular and shorter than pedicel; antennomeres 4–10 small, moniliform; apical antennomere acuminate ( Figs 1–2 ). Eyes lateral, rounded, very prominent, dark red, with yellow post-ocular area. Labrum subrectangular, similar to clypeus but shorter. Maxillary palpi 4-segmented, covered with short setae, basal palpomere smallest, apical palpomere largest, with a wide sensory area, relative length of palpomeres: 0.04, 0.08, 0.06, 0.14; palpomeres 1–3 subconical, palpomere 4 acuminate. Labial palpi very short, 3-segmented, palpomeres 1–2 rounded and wide, palpomere 3 subconical, nipple-shaped and slightly longer than preceding ones.

Thorax: Pronotum subtrapezoidal, almost as wide as elytral base; anterior margin arcuate, posterior margin bisinuate and 1.08 mm wide; lateral margin 0.55 mm wide, nearly straight along anterior half and expanded laterally on posterior half; posterolateral angles subacute. Pronotal disc with a well-developed, dorsomedial, longitudinal carina on distal half, and a wide, oval, deep depression to each side of carina ( Fig. 1 ); pronotal surface minutely punctate, covered with a minute, yellow vestiture with golden reflections, and long, dark red setae. Scutellum short, wider basally than long, apex rounded. Elytra with short yellow setae with golden reflections, and dark red long setae; lateral margins parallel on basal 0.75, then gradually converging posteriorly; humeral width 1.10 mm. Prosternum short, with anterolateral corners subtriangular; prosternal process subcylindrical, with lateral margins parallel and raised, deeply grooved longitudinally, apex bifid, ending in two parallel tips ( Figs 2, 3 ) which reach anterior half of mesoventrite. Mesoventrite shorter than metaventrite, with a wide groove for reception of prosternal process. Metaventrite large and bulky. Legs: Femora robust; tibiae slender, metatibia longer than metafemur, protibia with a tiny apicolateral denticle. Tarsomeres 1 and 2 ventrally lobed, with a thick sponge-like vestiture; ventral lobe of tarsomere 1 extending distally over basal 0.30 of tarsomere 2; tarsomere 2 the longest, twice as long as tarsomere 1, extending distally and completely covering tarsomeres 3, 4, and basal 0.80 of tarsomere 5; proportional length of tarsomeres: 0.50, 1.0, 0.13, 0.12, 0.57; apical claws long, curved, slender, each with a small basal tooth.

Abdomen: Vestiture short, fine and dense, whitish with yellow reflections. Ventrite VI usually hidden under ventrite V; ventrites I and II wide, with posterior margin curved anteriorly in the middle; ventrites III and IV narrow, with posterior margin straight; ventrite V with posterior margin slightly emarginate; ventrite VI very short, subtriangular, with posterior margin widely curved posteriorly; ventrite VII or anal plate, oval, subtriangular, narrow, covered with long whitish setae ( Fig. 2 ); pygidium subtriangular covered with long whitish setae. Genitalia: Short, wide, subrectagular, trilobate ( Figs 5–6 ); total length 0.56 mm, total width 0.24 mm. Parameres robust, 0.32 mm long, longer than penis; with internal margins fused at basal 0.13 in dorsal view ( Fig. 5 ), in ventrolateral view with a small tooth on internal margin near to apex ( Fig. 8 ). Penis 0.27 mm long, shorter than parameres ( Figs 6–7 ); in ventral view finger-like, bearing a ventral, longitudinal, long and straight sclerite which is 0.65 as long as penis ( Fig. 6 ). Phallobase concave in dorsal view; bulky, subcylindrical in ventral view, length 0.26 mm, width 0.24 mm.

Variation. Two specimens have yellow pronotum, slightly darker in the middle ( Fig. 4 ), and the first two ventrites yellow. Paratype measurements (in mm) (N=5): Total length, 2.35–3.0, mean = 2.80. Pronotum: posterior margin, 0.98–1.10, mean = 1.04; lateral margin, 0.50–0.65, mean = 0.57. Elytra: humeral width, 0.98–1.15, mean = 1.07.

Etymology. The name of this species comes from the latin adjective " bifidus " (divided into two sectors or portions), in reference to the apex of prosternal process which ends in two parallel tips.

Ecology. The specimens of P. bifidus sp. nov. were collected flying over turbulent rapids in the center of the stream, together with some specimens of P. triangularis sp. nov.

Remarks. Psephenops bifidus sp. nov. can be separated from other known Psephenops species by the characteristics listed in Table 1.

Short = when fully extenđeđ backwarđs, not reaching posterior margin of pronotum. Long = reaching or exceeđing posterior margin of pronotum Short = when the lobe of tarsomere 2 covers ventrally the full-length of tarsomeres 3-4 anđ basal half or less of tarsomere 5. Long = the same but reaching at least the 80% the length of 5.

Figures

FIGURES 1 – 4. Psephenops bifidus sp. nov., male: 1) habitus, dorsal view; 2) habitus, ventral view; 3) prosternum and prosternal process; 4) young adult, dorsolateral view. Specimens in alcohol. Scale bar for Figs 1, 2 and 4 = 1 mm.

FIGURES 5 – 8. Psephenops bifidus sp. nov., male genitalia: 5) dorsal; 6) ventral; 7) lateral; 8) ventrolateral. Scale bar = 0.14 mm.