Hexacylloepus maierae, 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 : 24-26

Hexacylloepus maierae sp. nov.

( Fig. 9 A–C)

Type locality: Suriname, Sipaliwini District.

Diagnosis: Antennae with thin setae at apex of each antennomere. Frontoclypeal suture straight. Pronotum with a long, wide, deep impression on disc, reaching the anterior and posterior margins. Prosternum with a pair of reddish-brown spots. Hypomera with a belt of tomentum reaching the anterior and lateral margins. Epipleura with tomentum. Tibiae each with a pair of spurs at apex, protibiae each with a row of short spines on distal half; meso- and metatibiae each with a groove on distal half, with two rows: one of short spines and the other of long setae. Abdomen with the disc of the first ventrite without tomentum. Male genitalia sharp; phallobase twice as long as wide; parameres reaching 2/3 of the penis length; penis with anterior quarter constricted, and slightly tapering toward the apex, apex sharp.

Description: Male. Body elongated, subparallel. Yellow coloured, with the antenna, mouthparts and legs reddish-brown. Total length: 1.64 mm. Greatest width: 0.65 mm.

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

Thorax: Pronotum as long as wide, arcuate anteriorly; sides sinuate and serrate, posterior margin smooth with two prescutellar foveae ( Fig. 9A ). Surface with micropunctures and short setae. Sublateral carinae complete, sinuous and raised ( Fig. 9A ). Longitudinal impression long, wide and deep on disc, reaching the anterior and posterior margin, and wider on middle portion.

Elytra twice as long as wide; anterior margin arcuate, lateral margin moderately arcuate and serrate; rounded apex ( Fig. 9A ). Humeri prominent. Surface with rows of punctures. Elytral suture moderately elevated. Carina short and elevated on interval IV, extending from base to 1/6 of the elytral length; sublateral carinae on intervals VI and VIII, extending from base to 3/4 of the elytral length. Epipleura covered with tomentum ( Fig. 9B ). Hind wings macropterous. Scutellum shield-like.

Prosternum broad, surface with micropunctures, anterior margin straight and lateral margin covered with tomentum and with a reddish-brown coloured spot. Prosternal process long, and beyond the procoxae; lateral margin flat; rounded apex; disc shallow. Notosternal suture slightly sinuous. Hypomera posteriorly wider than anteriorly, lateral margin with serrate surface with micropunctures, with a belt of tomentum reaching the anterior and lateral margins ( Fig. 9B ).

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

Legs (except tarsi) covered with punctures and tomentum ( Fig. 9B ). Coxae rounded; trochanter elongated; femora 4x as long as wide, 1/3 of the length of the elytra; tibiae long and thin, 8x longer than wide, 1/3 of the length of the elytra and with a pair of spurs at apex. Protibiae each with a row of short spines on distal half. Meso- and metatibiae each with a groove on distal half and with two rows: one with short spines and other with long setae. Tarsi elongate, with setae; apical tarsomere with the length of the basal four combined. Claws long and thin.

Abdomen ( Fig. 9B ): 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 covered with tomentum (excepted for disc of first ventrite). Disc of the first ventrite broad and flat. Fifth ventrite with lateral margins slightly produced posterolaterad and apex rounded with long setae.

Male genitalia ( Fig. 9C ): (Total length: 0.55 mm. Greatest width: 0.15 mm), symmetrical and acute. Phallobase twice as long as wide, moderately longer than the penis length. Parameres fused, and articulated with the phallobase, reaching 2/3 of the penis length; thin 6x as long as wide, with sharp apex and curved to internal margin. Penis with anterior quarter constricted, and slightly tapering toward the apex; apex sharp; fibula elongated, very narrow, approximately the same length as the penis; corona present, as an arrangement of tiny rod-like sclerotizations.

Female: External morphology similar to male, except for absence of the groove and row of spines on metatibiae.

Material examined: 15 specimens.

Distribution: Suriname: Sipaliwini District.

Male holotype: Holo- type | ♂ | SURINAME: Sipaliwini District / N3º55.600’ W56º11.300’, 600m / CSNR: Tafelberg Summit / nr Augustus Creek Camp / leg. A.E.Z. Short; 15.viii.2013 / UV light; SR13-0815-LT2 (NZCS) .

Paratypes: 14 specimens Para- type | SURINAME: Sipaliwini District / N3º55.600’ W56º11.300 ’, 600m / CSNR: Tafelberg Summit / nr Augustus Creek Camp / leg. A.E.Z. Short; 15.viii.2013 / UV light; SR13-0815-LT2 (4 NZCS; 5 SEMK; 5 MZSP) (MZSP 35760-35764) .

Etymology: maierae is a tribute to Dr. Crystal Maier, specialist in Dryopoidea and curator at the Museum of Comparative Zoology—Cambridge, Massachusetts, USA.

Comparative notes: Hexacylloepus maierae sp. nov. resembles H. smithi ( Grouvelle, 1898) , both having the longitudinal impression on pronotum long and wide; hypomera with a belt of tomentum reaching the anterior and lateral margins, and mesotibiae each with a groove with a row of spines. However, H. smithi has the frontoclypeal suture inconspicuous and disc of the first abdominal ventrite depressed, while H. maierae sp. nov. has the frontoclypeal suture straight and disc of the first abdominal ventrite flat.

Figures

FIGURE 9. Hexacylloepus maierae 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.