Hexacylloepus froehlichi, Polizei & Barclay & Bispo, 2020

Polizei, Thiago T. S., Barclay, Maxwell V. L. & Bispo, Pitágoras C., 2020, Hexacylloepus Hinton, 1940 rises again; 18 new species of a neglected genus (Coleoptera: Byrrhoidea: Elmidae), Zootaxa 4819 (1), pp. 6-48 : 13-16

Hexacylloepus froehlichi sp. nov.

( Fig. 4 A–C)

Type locality: Brazil, São Paulo State, Campos do Jordão.

Diagnosis: Antenna with a pair of long thin setae at apex of each antennomere. Frontoclypeal suture inconspicuous. Pronotum with a narrow and deep impression on disc. Hypomera with a complete belt of tomentum covering almost the entire anterior half portion. Epipleura with tomentum only in the internal margin. Profemora with a dense row of long setae on proximal 2/3. Pro- and mesotibiae each one with rows of spines and setae on distal half, and on metatibiae on distal 2/3. Abdomen with tomentum, first ventrite with a deep depression, with a pair of carinae extending towards and reaching the metaventrite; fifth ventrite with the apex glabrous. Male genitalia with the phallobase twice as long as wide; parameres reaching almost all the penis length; penis 6x as long as wide, with the apex rounded.

Description: Male. Body elongated, subparallel. Black colour, with the antenna, mouthparts and legs reddishbrown. Total length: 3.46 mm. Greatest width: 1.44 mm.

Head: surface with micropunctures separated from each other by their diameter. Antenna inserted on the anterior margin of the eyes, filiform, with 11 antennomeres, each one with a pair of long thin setae at apex. Frontoclypeal suture inconspicuous. Clypeus 3x as wide as long; anterior margin straight and posterior margin sinuous; surface similar to that of head. Labrum 3x as wide as long; antero-lateral angles rounded and with tuft of long setae, surface alutaceous. Maxillary palpus 4-segmented; terminal palpomere truncated apically. Labial palpus 3-segmented. Mentum and submentum broad. Gula rectangular. Genae covered with tomentum.

Thorax: Pronotum slightly longer than wide, arcuate anteriorly and laterally; posterior margin smooth with two prescutellar foveae ( Fig. 4A ). Surface with micropunctures. Sublateral carinae complete, sinuous and raised. Longitudinal impression wider and deep on disc, reaching the anterior and posterior margins.

Elytra approximately twice as long as wide; anterior margin arcuate, lateral margin arcuate and moderately serrate; rounded apex ( Fig. 4A ). Humeri rounded and prominent. Surface with puncture and rows of setae. Elytral suture moderately elevated. Carinae strongly raised. Carina on interval IV, extending from base to 1/4 of the elytral length; sublateral carinae on intervals VI and VIII, extending from base to 3/4 of the elytral length. Epipleura with tomentum on internal margin ( Fig. 4B ). Hind wings macropterous. Scutellum oval, strongly raised.

Prosternum wide, strongly elevated, with a pair of carinae reaching the anterior margin; surface with micropunctures, anterior margin straight and lateral margin covered with tomentum. Disc depressed. Prosternal process wide and beyond the procoxae; lateral margin strongly raised; straight apex; disc strongly deep. Notosternal suture sinuous. Hypomera wider posteriorly than anteriorly, lateral margin slightly serrate surface with micropunctures, with a complete belt of tomentum covered almost the entire anterior half portion ( Fig. 4B ).

Mesoventrite with a deep groove to receive the prosternal process. Mesepimeron and mesepisternum covered with tomentum. Metaventrite broad with a strong longitudinal medial depression; surface with micropunctures; and with sides covered with tomentum.

Legs (except tarsi) covered with punctures and tomentum ( Fig. 4B ). Coxae rounded; trochanter elongated; femora 5x longer than wide, 1/3 of the length of the elytra; tibiae long, 6x as long as wide, 1/3 of the length of the elytra. Profemora with a dense row of long setae on proximal 2/3. Pro- and mesotibiae each with rows of spines and setae on distal half and metatibiae on distal 2/3. Tarsi elongate, with setae; apical tarsomere with the length of the basal four combined. Claws long and thin.

Abdomen ( Fig. 4B ): five ventrites; as long as wide. Anterior and posterior margins straight on the first and second ventrites and arcuate on the subsequent ventrites, lateral margins rounded. Surface densely covered with tomentum. Disc of the first ventrite with a deep depression without tomentum, with a pair of carinae extending towards and reaching the metaventrite. Second ventrite with the anterior half without tomentum. Fifth ventrite with the apex rounded and glabrous.

Male genitalia ( Fig. 4C ): (Total length: 1.06 mm Greatest width: 0.26 mm), symmetrical. Phallobase twice as long as wide, longer than the penis length. Parameres articulated with the phallobase, reaching almost all the penis length; wider at base than apex; apex slightly rounded. Penis 6x as long as wide, with the lateral margin straight; anterior half slightly wider than posterior; apex rounded; fibula elongated approximately the same length of the penis and constricted at apex; corona present, arranged as tiny rod-like sclerotizations.

Female: External morphology similar to male, except by a moderate depression on metaventrite disc and disc of the first abdominal ventrite.

Material examined: 24 specimens.

Distribution: Brazil: São Paulo State.

Male holotype: ♂ | Holo- / type | Brazil-SP-Campos do / Jordão Pq Estadual / 1987 L.G.Oliveira & / C.G.Froehlich leg. | MZSP 35713 ( MZSP) .

Paratypes: 23 specimens: ♂ | BRASIL. São Paulo. Campos do / Jordão. Parque Estadual Campos / do Jordão. Riacho afl. Casquilho / 06.X.2019 Polizei, T. & Fusari, L. / leg. 22°40’39,2”S 45°28’18,4”W | MZSP 31364. (MZSP in DNA-grade collection) . ♀ | BRASIL. São Paulo. Campos do / Jordão. Parque Estadual Campos / do Jordão. Riacho Serrote / 04.X.2019 Polizei, T. & Fusari, L. / leg. 22°40’01,7”S 45°26’57,1”W | MZSP 31365. (MZSP in DNAgrade collection). Para- / type | BR-SP-Campos do / Jordão—P. E. Campos do / Jordão 06.VII.2013 / T.T.S.Polizei & L.S.M.Costa leg. (2 ♂ 2 ♀ MZSP; 1 ♂ 2 ♀ NHMUK). Para- / type | BR-SP-Campos do / Jordão—P. E. Campos do / Jordão 18.V.1993 / R. Galharada / Exp. MZUSP leg. (3 MZSP). Para- / type | Brazil-SP-Campos do / Jordão Pq Estadual / 1987 L.G.Oliveira & / C.G.Froehlich leg. (MZSP). Para- / type | BRASIL. São Paulo. Campos do / Jordão. Parque Estadual Campos / do Jordão. 08.IX.2005 Riacho / Celestina. M.R.Spies leg. (10 MZSP). (MZSP 31154-31163, 35708-35712, 42074-42076) .

Etymology: froehlichi is a tribute to Professor Dr. Claudio Gilberto Froehlich, collector and pioneer in the studies of aquatic insects in Brazil.

Comparative notes: Based on the combination of body size and the strongly raised carinae/scutellum, H. froehlichi sp. nov. is very different from all the other Hexacyllopeus species. However, because of the large size, robust body and black overall colour, it is similar to H. grandis sp. nov. However, H. froehlichi sp. nov. is smaller than H. grandis sp. nov. and can be differentiated by the inconspicuous frontoclypeal suture, short longitudinal impression on pronotum and epipleura with only the internal margin covered with tomentum; in H. grandis sp. nov. has the straight frontoclypeal suture, longitudinal impression on pronotum long and narrow and epipleura completely covered with tomentum.

Figures

FIGURE 4. Hexacylloepus froehlichi sp. nov.. Male. Holotype. (A–B) Habitus. (A) Dorsal view. (B) Ventral view. (C) Ventral view of male genitalia. Scale bars: (A–B) = 0.5mm. (C) = 0.1mm.