Sicilicula conjugalis,

Perkins, Philip D., 2017, Hydraenidae of Madagascar (Insecta: Coleoptera), Zootaxa 4342 (1), pp. 1-264: 205-207

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Sicilicula conjugalis

new species

Sicilicula conjugalis  , new species

Figs. 195View FIGURE 195 (habitus), 197 (aedeagus), 304 (map) Type Material. Holotype (male): Fianarantsoa, Namorona River , 7 km SW Ranomafana, from stream with mossy rocks and sandy bottom, montane rainforest, elev. 1200 m, 21° 16' S, 47° 26' E, 23 x 1988, W. E. Steiner, C. Kremen, R. Van Epps ( USNM)GoogleMaps  . Paratypes (39): Same data as holotype (38 USNM); Fianarantsoa, Namorona River , 7 km W Ranomafana, from stream with mossy rocks and sandy bottom, montane rainforest, elev. 1100 m, 21° 15' S, 47° 25' E, 1–7 xi 1988, W. E. Steiner (1 USNM).GoogleMaps 

Differential Diagnosis. Similar to S. bergsteni  in having the lateral lobes of the pronotum relatively small, convex, not margined, and lacking denticulations. Males of S. conjugalis  are differentiated by the markedly arcuate mesotibiae, whereas females are differentiated by the unique skirt of setae on the posterior border of the fifth ventrite ( Fig. 195View FIGURE 195). The general shape of the aedeagi also show a relationship, but the distal processes of the two species differ markedly ( Figs. 196, 197View FIGURES 196 – 198).

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.62/0.64; head width 0.44; pronotum 0.38/0.50, PA 0.32, PB 0.36; elytra 0.88/0.64. Dorsum black, maxillary palpi and legs brown.

Head with labrum/clypeus/frons length rations as 10/5/8. Labrum prominently bilobed, median raised area extended onto lobes, finely sparsely punctulate, interstices shining. Clypeus with anterior margin distinctly narrower than posterior. Clypeus and frons strongly shining, clypeus finely sparsely punctulate, frons even more sparsely punctulate, vertex nearly impunctate, size of punctures much smaller than 1xef. Anteocellar sulci deep. Ocelli distinct.

Pronotum cordate, widest in front of middle; anterior angles obtuse, posterior rectangular; sides with lateral lobes convex, not margined, and not crenulate, sides behind lateral lobes extremely finely margined; anterior margin shallowly arcuate over median 3/4, without hyaline border; discal reliefs strongly shining, very finely and very sparsely punctulate, without setae. Anterior and posterior ¼ and lateral lobes coarsely deeply punctate. Discal foveae ( Fig. 195View FIGURE 195) large and deep, coarsely punctate as is posterior border.

Elytra with disc very slightly depressed in front of midlength, sides weakly arcuate, widest at posterior 2/3, apices separately rounded; sides smooth, moderately explanate (but see female); posterior declivity gradual. Serial punctures large and deep, without discernable setae, on disc slightly larger than largest pronotal punctures, interstices about 1xpd or slightly less; without granules. Series rather deeply striate-impressed, series one and two more weakly so than other series, becoming obsolete at posterior declivity. Intervals weakly rounded, width on disc about 2xpd; intervals without setae.

Mentum and submentum finely sparsely punctulate, interstices shining. Metaventral disc with oval impression in basal 1/2. Thoracic ventrites and abdominal ventrites 1–5 clothed with dense setae except glabrous midlongitudinal prosternal ridge, glabrous dull mesoventral plaques and small glabrous strongly shining inverted V-shaped basomedian area on mesoventrite in front of intercoxal sternite. Ventrite 6 shining, with setigerous punctures in anterior 1/2. Pro- and mesotibiae arcuate, metatibiae straight. Wings fully developed.

Aedeagus ( Fig. 197View FIGURES 196 – 198) length ca. 0.46 mm, main piece 0.29 mm, distal process beyond main piece 0.17 mm; main piece slightly widened in distal ½ in ventral view; distal process arcuate in lateral view, widest at ca. midlength; setae of main piece rather long.

Female: size (length/width, mm): body (length to elytral apices) 1.50/0.68; head width 0.42; pronotum 0.35/ 0.47, PA 0.32, PB 0.35; elytra 0.85/0.68. Elytral explanate margin very wide, widest slightly behind midlength, apices conjointly rounded, except sutural apices dehiscent. Fifth abdominal ventrite with posterior skirt of long, dense setae ( Fig. 195View FIGURE 195).

Etymology. Named in reference to the sexual dimorphisms.


Smithsonian Institution, National Museum of Natural History