Macrelmis fluminensis, Sampaio, Brunno Henrique Lanzellotti, Passos, Maria Inês Da Silva Dos & Jr, Nelson Ferreira-, 2012

Sampaio, Brunno Henrique Lanzellotti, Passos, Maria Inês Da Silva Dos & Jr, Nelson Ferreira-, 2012, Two new species of Macrelmis Motschulsky (Coleoptera: Elmidae) and a new record of Macrelmis isis (Hinton) from Southeastern Brazil, Zootaxa 3478, pp. 164-168 : 164-166

Macrelmis fluminensis sp. nov.

( Fig. 1 )

Diagnosis. Head surface with granules slightly bigger than eye facet, separated by one diameter. Pronotum with a pair of sublateral carinae beginning on posterior margin and reaching the anterior fifth. Apices of elytra projected and conjointly rounded. Male genitalia with aedeagus slightly bigger than parameres; narrow at base narrowing even more on distal third; digitiform apex. Parameres wide at base, narrowing abruptly on apical half; apex feebly turned to aedeagus.

Description. Holotype male. Total length 3.25mm; head width 0.72mm, length 0.24mm; pronotum width 1.22mm, length 1.00mm; elytra width 1.50mm, length 2.33mm. Body dark brown, feebly reddish; antennae reddish brown; legs reddish brown.

Head surface with granules slightly bigger than facet of eyes; separated by one diameter. Antennae filiform inserted between eyes and clypeus. Clypeus truncate, with lateral angles rounded; labrum convex with fine sparse setae, which are bigger near anterior margin.

Pronotum with anterior margin convex on the middle region; anterolateral margins acute; lateral margin convex and crenulated; greatest width at middle third; surface with granules as big as facet of eyes, separated by one diameter; a pair of sublateral carina from posterior margin to anterior fifth; longitudinal and transversal impressions absent. Elytra with anterior margin convex and subparallel lateral margins; projected and conjointly rounded apex. Interestrial intervals with granules feebly bigger than those of pronotum, and separated by less than one diameter on anterior half; posterior half with fine recumbent setae. Epipleura reaching the ventrite V, nontomentose, and with granules like those of interestrial intervals. Scutellum raised, as long as wide, with granules similar to those of pronotum. Hypomere wide, with granules bigger than facet of eyes, separated by one diameter or less. Prosternum surface with granules like on hypomere; prosternal process narrow between fore coxae (about 1/5 of anterior margin width), extending beyond them with an acute apex. Mesosternum with a wide and shallow groove, for reception of prosternal process, with granules bigger than on hypomeron. Metasternum disc with flattened granules, bigger than facet of eyes, separated by less than one diameter; longitudinal impression more conspicuous near posterior margin.

Coxae, trochanters, femurs, and tibiae granulose. Fore femur with tomentum fringe on apical 2/3, on anterior face; fore tibia with tomentum fringe on apical 3/4, on anterior face; middle tibia and hind tibia with a tomentum fringe on apical 2/3, on posterior face; tarsomeres with some short ventral setae.

Abdomen surface with granules smaller than those of metasternum, except on a middle area on ventrites I–III; granules separated by less than one diameter near the smooth area and sparser on the side areas.

Male genitalia with aedeagus slightly longer than parameres, wider on the base, near the basolateral apophysis; distal third narrower and digitiform apex. Parameres wide on base and much narrow on apical half. Phalobase longer than wide (5:3); slightly longer than half of genitalia length.

Variation. Measurements of body vary in total length 3.15–3.90mm; head width 0.60–0.76mm and length 0.20–0.40mm; pronotum width 1.18–1.26mm and length 0.98–1.06mm; and elytra width 1.34–1.53mm and length 2.24–2.43mm.

Comparative notes. This new species is similar to M. tijucana and to the group M. aristaea (Hinton) because of the absence of impressions on pronotum; it differs from these species by the shape of genitalia and because it has two fringes of tomentum on middle tibiae, while M. tijucana and group M. aristaea have only one fringe. The new species is different from those of group M. celsa (Hinton) and M. granigera (Sharp) , because of the presence of carinae and absence of gibbosities, respectively.

Type material. Holotype male, Brazil, Rio de Janeiro, Macaé municipality, Sana, afluente de 2a ordem do Rio Boa Sorte, 22°20'34.7"S 42°11'02.6"W, 373m, 19.II.2009, J.L. Nessimian, G.A. Jardim, I.C. Gonçalves, B.H.L. Sampaio, L.L. Dumas leg. [DZRJ-Coleoptera 5609]. Paratypes, 4 specimens – same data of holotype [DZRJ- Coleoptera 5610]; 1 male – Rio da Glória, 22°19'53.0"S 42°10'16.7"W, 398m, 17.II.2009, B.H.L. Sampaio, L.L. Dumas leg. [DZRJ-Coleoptera 5613]; 1 male— Brazil, Rio de Janeiro, Nova Friburgo municipality, Rio Bonito de Lumiar, Ramalhete, afluente de 3ª ordem do Rio Bonito, 22°24'38.2"S 42°20'38.6"W, 669m, 06.III.2009, A.L.H. Oliveira leg. [ MNRJ].

Etymology. The specific epithet fluminensis is a gentilic to natives from Rio de Janeiro state, the place of origin of the type material, the Macaé river basin.

Figures

FIGURE 1. Macrelmis fluminensis sp. nov. (Holotype): a—Dorsal view; b—ventral view; c—male genitalia.