Hydraena (Hydraenopsis) matthiasi Deler-Hernández, Fikáček & Delgado, 2017

Deler-Hernández, Albert, Fikáček, Martin & Delgado, Juan A., 2017, The Hydraenidae of Cuba (Insecta: Coleoptera) III. Description of two new hygropetric species of Hydraena Kugelann, Zootaxa 4250 (5), pp. 434-446 : 439-443

Hydraena (Hydraenopsis) matthiasi Deler-Hernández, Fikáček & Delgado , new species

( Figs 4 ¯6; 7c, d; 8b, e)

Type locality. Cuba, Granma Prov., Turquino National Park, Aguada de Joaquín, 20.01447°N 76.84065°W, 1359 m.

Type material. Holotype (male): Cuba. Granma, Turquino National Park, Aguada de Joaquín , 20.01447°N 76.84065°W, 1359 m, 27.ix.2014, coll., A. Deler-Hernández, Hygropetric habitat [printed] / “ HOLOTYPE, HYDRAENA matthiasi, Det :. A. Deler-Hernández et al. 2016 [red printed] ( NMPC) . Paratypes. 17 specimens with same data as for the holotype : 7 males, 4 females dry-mounted (NMPC, CDUM, NHMW, MCZ); 1 male, 2 females in alcohol (NMPC); 2 females in alcohol (IBE); 1 female, DNA extracted and dry-mounted after extraction (IBE/DNA voucher IBE-AN508). GenBank accession number LT627659 .

Descriptions. Male. Habitus as in Fig. 4 . Body length (taken from anterior margin of labrum to elytral apex) about 1.40¯ 1.43 mm. Colour: Head (dorsal) dark brown to black; pronotal disc dark brown; anterior angles and lateral half of anterior margin of pronotum slightly paler; elytra dark brown, with lateral margin, including the apical region, paler; maxillary palpi, antennae and legs pale brown to testaceous; distal half of terminal maxillary palpomere darkened.

Head. Labrum moderately excised anteriorly; lobes evenly rounded. Clypeus with fine and sparse punctures. Frons finely sparsely punctuate. Clypeal and frontal punctures denser on lateral areas than medially; interstices shining.

Thorax. Pronotum distinctly wider than long, widest near middle; anterior margin straight; anterior angles rounded, sides finely denticulate, slightly curved and convergent to anterior angle, sinuate and convergent to posterior border; anteroexternal and posteroexternal foveolae marked, internal foveolae less evident; punctures moderately impressed, of similar size to those of frons; interstices shining. Elytra elongate oval, lateral explanate margin moderately developed, not reaching apex; apices in dorsal view separately rounded; with 14¯15 (10 between suture and shoulder) rows of impressed punctures, rows quite regular; punctures round, moderately impressed, of approximately same size as on pronotum; interstices not elevated, shining to matt. Mesoventrite with internal and external carinae slightly divergent posteriad; median carina short and thin, not reaching base of intercoxal process, remarkably thinner than external and internal carinae; intercoxal process narrow, sides nearly parallel; apex blunt, width at apex approximately 0.3 distance between internal and median carinae. Base of mesocoxal cavities rounded. Metaventrite with plaques well developed, straight, slightly converging anteriorly; width of each plaque 1.5 width of intercoxal process; plaque separated approximately twice plaque width. Legs moderately short and stout; protibiae broad, with a small spine on inner face near apex ( Fig. 7 c); metatibiae arcuate, enlarged apically ( Fig. 7 d).

Abdomen. Male terminal sternite and spiculum gastrale as in Fig. 6 a; terminal sternite subtrapezoidal, with anterior margin concave, posterior margin rounded and lateral margins sinuate; spiculum moderately long and curved, not firmly connected with sternite. Male genitalia as in Figs 5 a–c; main piece long, only slightly dilated distally both in lateral and dorsolateral views ( Figs 5 b–c) but not in ventral view ( Fig. 5 a); with two distinct processes at the apex: a slender, elongate gonopore-bearing process (flagellum) and a falcate laminar process; a subdistal lateral crooked projection of main piece ( Figs 5 a-c) offers the impression of a third process; parameres inserted near midlenght of main piece, left paramere relatively long and slender, left shorter.

Female. Similar to male in shape and size; pro- and metatibiae not modified; gonocoxite as in Fig. 6 c, semicircular, transverse, condyles well developed, outer plate with trichoid setae on disc and lateroposterior areas and two tufts of subapical setae, inner plate distinctly exposed basally, cavea suboval; tergite X as in Fig. 6 b, suboval, with hyaline margin emarginated medially; spermatheca as in Figs 6 d–e, with proximal portion slightly curved, central portion enlarged and strongly curved and distal portion long; spermathecal gland smooth and rounded; spermathecal duct wide.

Differential diagnosis. Hydraena matthiasi is externally very close to H. blancae and H. franklyni with similar body coloration and shape. However, it can be externally distinguished from H. blancae by its slightly larger size and by modified male metatibiae ( Figs 7 b, d). The shape of the metaventral plates can be also useful to distinguish both species, being wider in H. blancae ( Fig. 8 d) than in H. matthiasi ( Fig. 8 e) and, the base of the mesocoxal cavities rounded ( Fig. 8 e). Furthermore, H. matthiasi is easily distinguished from H. blancae by the morphology of their aedeagi ( Figs 2 , 5 ), and their male and female terminalia ( Figs 3 , 6 ).

The evident similarities in the shape of the male and female genitalia indicate a very close relationship between H. matthiasi and H. franklyni . They can only be reliably separated by a close examination of the male aedeagus. In ventral view, the apical portion of the right process of the distal lobe is clearly more angulate in H. franklyni (see fig. 34 in Deler-Hernández & Delgado 2012), than in H. matthiasi ( Fig. 5 c). In dorsolateral view, this angulation is not so evident but the main piece of H. franklyni is clearly more globose ( Figs 8 a–b). The subdistal lateral process of the main piece is slender and less twisted in H. matthiasi and the flagellum is also slender in H. matthiasi ( Figs 8 a–b). A less evident but useful character is the length of the mesoventral median carina, which reaches the base of the intercoxal process in H. franklyni ( Fig. 8 c) being shorter, not reaching the base of the intercoxal process in H. matthiasi ( Fig. 8 e).

Etymology. The new species is dedicated to Matthias Seidel, fellow co-worker of the first author at Charles University and a very enthusiastic entomologist specializing on Scarabaeidae .

Distribution. Currently only known from the type locality (Turquino National Park) in eastern Cuba ( Fig. 9 ).

Habitat. Hygropetric. Hydraena matthiasi has been collected on wet rock faces in a well preserved cloud forest at 1359 m a.s.l.

Figures

FIGURE 2. Hydraena blancae (holotype): aedeagus in (a) ventral (b) lateral, and (c) dorsolateral views. Scale bar 0.1 mm.

FIGURE 3. Hydraena blancae male (holotype) and female (paratype) terminalia: a, male terminal sternite and spiculum; b, female tergite X; c, gonocoxite; d – e, spermatheca. Scale bar 0.1 mm.

FIGURE 4. Habitus of Hydraena matthiasi (holotype). Scale bar 0.5 mm.

FIGURE 5. Hydraena matthiasi (holotype): aedeagus in (a) ventral (b) lateral, and (c) dorsolateral views. Scale bar 0.1 mm.

FIGURE 6. Hydraena matthiasi male (holotype) and female (paratype) terminalia: a, male terminal sternite and spiculum; b, female tergite X; c, gonocoxite; d – e, spermatheca. Scale bar 0.1 mm.

FIGURE 7. Hydraena blancae (paratype male): a, protibia; b, metatibia. Hydraena matthiasi (paratype male): c, protibia; d, metatibia. Scale bar 0.1 mm.

FIGURE 8. Aedeagi in dorsolateral views: a, Hydraena franklyni; b, Hydraena matthiasi. Thoracic venter (SEM images): c, Hydraena franklyni; d, Hydraena blancae; e, Hydraena matthiasi.

FIGURE 9. Geographical distribution: Hydraena matthiasi (1); Hydraena franklyni (2); Hydraena blancae (3).