Pilielmis Hinton, 1971

Pinedo-Garcia, Raul Bismarck, Polizei, Thiago Tadeu Silva, Hamada, Neusa & Nascimento, Jeane Marcelle Cavalcante Do, 2024, Systematics of Pilielmis Hinton, 1971 (Coleoptera: Dryopoidea: Elmidae), Zootaxa 5421 (1), pp. 1-68 : 6-7

Pilielmis Hinton, 1971

Pilielmis Hinton, 1971: 161 (original description); Passos et al. 2010 (taxonomic record); González-Córdoba et al. 2015 (taxonomic record); Polizei & Barclay, 2019 (taxonomy); Passos et al. 2022 (identification key).

Pilielmis halia Hinton, 1971 : type species (by original designation).

Diagnosis. Body subparallel or suboval, with short golden setae. Pronotum with a pair of sublateral carinae; longitudinal impression on disc; oval depression on basal 2/5. Hypomerum covered by tomentum. Elytra with a short carina on interval IV extending up to basal 1/3 and a sublateral carina on interval VI, extending from the humerus to approximately the apex. Claws large and slender, with one tooth near base. Male with phallobase longer than wide, penis longer than wide, corona present. Female with coxites elongated, subdivided by a transverse line; apex of apical coxite projected laterally, inner margin with an uninterrupted row of short setae.

Male redescription. Body subparallel or suboval. Head. Partially retractable; without impressions; surface with short golden setae. Eyes black, slightly projected. Antennae filiform, with 11 antennomeres. Labrum suboval or subrectangular; lateral and anterior margins with long setae; surface with setae distributed along its entire length. Mandibles partially symmetrical, with three apical teeth; prostheca membranous, with short setae on posterior margin and lobes on the apex. Maxilla: cardo with sinuous lateral margin; stipe longer than wide; maxillary palpus with four palpomeres; palpomeres I–III with setae on surface; palpomere IV longer than the basal ones combined, with a truncated or rounded apex, with setae and sensory pores; galea with two sections, apical section wider than the basal one; apex with a fringe of long setae, surface with thin setae; basal section as long as wide; lacinia longer than wide, with four tufts of long, thin setae at apex, with long setae on inner lateral margin, surface with setae along its entire length. Labium: mentum wider than long, covered by setae; labial palpus with three palpomeres; palpomere III longer than the basal two combined, with setae and sensory pores, apex rounded or truncated; ligula wider than long, anterior region with thin, thick setae and sensory pores; surface with thin, thick setae; anterolateral angles rounded. Gena with tomentum.

Thorax. Pronotum wider than long; anterior margin rounded; lateral margin convex or sinuous, with crenulations; posterior margin sinuous; with a pair of sublateral carinae extending from the base to near the apex; longitudinal impression on disc; oval depression on basal 2/5; surface of the pronotal disc covered by short golden setae; with a pair of prescutellar fovea. Elytra longer than wide; anterior margin smooth; lateral margins with crenulations; apex rounded or projected; humerus slightly projected; with a short carina on interval IV extending up to basal 1/3 and a sublateral carinae on interval VI extending from the humerus to near apex. Epipleura narrow, wider anteriorly and covered by tomentum. Metathoracic wings, when present, with the costal and subcostal veins fused near the sclerites; middle radial veins fused posteriorly and extending to near posterior margin; cubital vein reaching the posterior margin; wings with posterior margin with a row of short, thin setae. Hypomerum longer than wide, covered by tomentum. Prosternum wider than long. Proepimerum and proepisternum covered by tomentum. Mesoventrite wider than long, with mesal cavity to receive the prosternal process, anterior margin sinuous. Metaventrite wider than long; lateral margins covered by tomentum; discrimen conspicuous. Legs covered by tomentum, except tarsus. Procoxa partially covered by tomentum. Trochanter longer than wide. Femora narrowing towards apex. Tibiae elongated and slender; metatibia with a row of spines on the apical half. Apical tarsomere longer than the basal ones combined, with short setae at apex. Claws large and slender, with a tooth near base.

Abdomen. Ventrite V with rounded apex. Tergite VIII subtriangular. Sternite VIII with rounded posterior margin; posterolateral region projected, acute; anterior median projection longer than sternite. Segment IX forming a subrectangular genital capsule surrounding aedeagus; divided from the apex up to 1/3 basal. Genitalia. Phallobase longer than wide. Parameres shorter than penis, with sensory pores at apex and on lateral margins. Penis longer than wide, apex with sensory micropores; basolateral process longer than wide; corona present; fibula the same length as the penis.

Female redescription. General morphology similar to male. Ovipositor: valvifer membranous, longer than the coxites, with sensory pores on the posterior portion. Baculus sclerotized, elongated and sinuous. Coxites elongated, subdivided by a transverse line; basal coxites wider than long, with sensory pores; apical coxite longer than the basal one; apex projected laterally; inner margin with an uninterrupted row of short setae; surface with sensory pores. Styles slightly divergent.

Comparative notes. Pilielmis resembles Microcylloepus Hinton, 1935 , Hexacylloepus Hinton, 1940 and Hintonelmis Spangler, 1966 by sharing the pronotum with sublateral carinae and a longitudinal impression on the disc. Among these genera, Pilielmis can be distinguished from specious Microcylloepus by having a short carina on interval IV and a sublateral carina on the elytral interval VI, one tooth at the base of the claws, and no pair of oblique impressions on the pronotum, while Microcylloepus has a pair of sublateral carinae on the elytral intervals VI and VIII, the tooth at the base of the claw is absent and the pair of oblique impressions on the pronotum is present. Concerning Hexacylloepus , both genera have a tomentum belt in the hypomerum; however, they can be easily differentiated as follows: in Hexacylloepus the basal tooth of the claw is absent (except in Hexacylloepus iassu Polizei, Barclay & Bispo, 2019 ) and there is a pair of sublateral carinae on the elytra intervals VI and VIII; in Pilielmis , the claw tooth is present and there is only one sublateral carina on the elytral interval VI. Finally, Pilielmis also shares with Hintonelmis the presence of the basal claw tooth; however, the two genera can be distinguished by the following characteristics: in Pilielmis the prosternal process has a rounded posterior margin, pronotum with a complete sublateral carinae, and the carinae are present on the IV and VI elytral intervals; in Hintonelmis , the prosternal process has a straight/truncate posterior margin, a short or absent sublateral carinae on pronotum, and the carinae are present on the VI and VIII elytral intervals.

Distribution: Venezuela, Colombia, French Guiana, Suriname *, Brazil, and Peru * ( Fig. 1 ).

Figures

FIGURE 1. Map of SouthAmerica with detailed area indicating the distributional records forPilielmis Hinton, 1971 (Coleoptera: Elmidae).