Pilielmis shepardi Polizei & Barclay, 2019

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 : 41-46

Pilielmis shepardi Polizei & Barclay, 2019

( Figs 1 , 27–30 , 41G )

Pilielmis shepardi Polizei & Barclay, 2019: 282 (original description).

Diagnosis. Body suboval; general coloration black; elytra with yellowish-brown marks (a pair on the humeral region, a pair on the apical half of the disc, and a mark on the apex along the elytral suture); metathoracic wings absent; abdomen with a projection on the anterior margin of the ventrite I; abdomen with ventrite V fused to sternite VIII. Male with phallobase 2.3x longer than wide; parameres reaching approximately 3/5 the length of the penis; penis 4x longer than wide; basolateral process 2x longer than wide.

Male redescription. Length: mean = 1.62 mm; width: mean = 0.79 mm (n = 3). Body suboval ( Figs 27A , 41G ); general coloration black, with yellowish-brown marks, mouthparts, and antennae yellowish-brown.

Head. Antennae with uniform coloration, yellowish-brown ( Fig. 27D ). Labrum ( Fig. 28A ) subrectangular, 2x wider than long, with lateral margins rounded; anterolateral margins with long setae; dorsal surface with short, sparse setae along its entire length. Mandible ( Figs 28C, D ): lateral lobe rounded; condyle semicircular, 2x wider than long. Maxilla ( Fig. 28B ): cardo subtriangular, margin sinuous; stipe longer than wide; palpomere IV as long as the basal ones combined, apex truncated, with setae; galea with basal section subcylindrical, 1.5x longer than wide, apical segment 2x longer than wide, with long setae; lacinia subrectangular, 2x longer than wide; with long setae on lateral margin. Labium ( Fig. 28E ): mentum subrectangular, 2x wider than long, lateral margins sinuous, with setae; postmentum subtriangular, 4x wider than long, with setae on lateral margins; prementum subrectangular; ligula subrectangular, 3.5x wider than long, anterolateral region rounded, lateral margins slightly rounded, with short spines, surface with spines and short, thin setae; labial palpomere III with rounded apex.

Thorax. Pronotum ( Fig. 27A ) slightly wider (0.55 mm) than long (0.48 mm); lateral margins sinuous, with crenulations; anterolateral and posterolateral angles acute; with a yellowish mark on anterior 1/3; with a pair of sinuous, weakly raised sublateral carinae; longitudinal impression on the disc shallow; surface of the pronotal disc with golden short setae. Elytra ( Fig. 27A ) subparallel, 1.3x longer than wide (length = 1.08 mm; maximum width = 0.79 mm); apex rounded; humerus slightly projected; with yellowish-brown marks (a pair on the humeral region, a pair on the apical half of the disc, and a mark on the apex along the elytral suture). Epipleura ( Fig. 27B ) narrow, wider anteriorly, covered by tomentum. Scutellum pentagonal, flat. Metathoracic wings absent. Hypomeron 5x longer than wide. Prosternum ( Fig. 27B ) 0.62x longer than wide, anterior margin slightly concave; anterolateral angles rounded. Prosternal process ( Fig. 27B ) longer (0.18 mm) than wide (0.13 mm). Mesoventrite ( Fig. 27B ) wider (0.39 mm) than long (0.11 mm); anterior margin sinuous, convex in the median region; posterior margin truncated between the mesocoxae. Metaventrite ( Fig. 27B ) 2x wider than long; disc flat; lateral margins covered by tomentum; anterior margin truncated between mesocoxae. Hind legs ( Fig. 27B, C ). Trochanter 2x longer than wide. Femora 4x longer than wide. Tibiae approximately 7x longer than wide. Apical tarsomere 1.3x longer than the basal ones combined. Claws large and slender, with a tooth near base.

Abdomen. Ventrites I–IV without tomentum on the disc ( Fig. 27B ); ventrite V fused to sternite VIII, covered by setae ( Fig. 29B ). Tergite VIII ( Fig. 29C ) 1.3x wider than long, posterior margin rounded; surface with thin, short setae and microspines. Sternite VIII ( Fig. 29B ) 2.8x wider than long; anterior median projection 1.7x longer than the sternite body length. Segment IX ( Fig. 29D ) subtriangular, with rounded apex; with short spines. Genitalia ( Fig. 29A ). Phallobase 2.3x longer than wide, approximately the same length as the penis. Parameres 3.3x longer than wide, reaching approximately 3/5 the length of the penis; base wider than apex; apical region rounded; lateral margins without crenulations. Penis 4x longer than wide, apical region subtriangular; lateral margins slightly sinuous; surface with sensory micropores throughout the area; basolateral process 2x longer than wide.

Female description. Externally similar to male. Length: mean = 1.65 mm; width: mean = 0.74 mm (n = 2). Ventrite V fused to sternite VIII ( Fig. 30B ). Tergite VIII subtriangular, wider than long, posterior margin rounded; surface with setae, spines and microspines. Sternite VIII ( Fig. 30B ) 2.2x wider than long; anterior median projection 1.4x longer than the sternite body length. Ovipositor ( Fig. 30A ): valvifer 2.4x longer than the coxites, posterior margin with sensory micropores. Apical coxite 3x longer than wide, 1.3x longer than the basal one. Stylus slightly curved, measuring approximately 1/4 the length of the apical coxite; apex with short setae.

Comparative notes. As previously discussed, P. shepardi resembles P. murcia by sharing a body suboval, a similar general pattern of marks on the elytra (a pair on the humeral region, a pair on the apical half of the disc, and a mark on the apex along the elytral suture) and by the metathoracic wings absent. For details about how to differentiate the two species, see the discussion presented for P. murcia .

Distribution: Venezuela ( Fig. 1 ).

Material examined. Paratypes: Venezuela, Bolivar, nr. Ikabaru, 110 km, SW Sta. Elena de Uairen , 04.vii.1987 ; Polizei & Barclay det. 2019 (pinned and slide) (2♂ and 1♀ in MZSP) . Additional material. VENEZUELA. Bolivar: Parque Gran Sabana, Salto Kamá , 10.x.1996, 05°25′0.15′′ N, 61°13′1.22′′ W, Hamada et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (1♂ in INPA) ; 11.x.1996, 05°48′9.39′′ N, 061°25′1.11′′ W, Hamada et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (1♀ in INPA) .

Figures

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

FIGURE 27. Pilielmis shepardi Polizei & Barclay, 2019 (Coleoptera: Elmidae). Adult male, habitus. (A) Dorsal view. (B) Ventral view. (C) Lateral view. (D) Front view. Scale bars = 0.5 mm.

FIGURE 28. Pilielmis shepardi Polizei & Barclay, 2019 (Coleoptera: Elmidae). Adult mouthparts. (A) Labrum, dorsal view. (B) Maxilla, dorsal view. (C) Mandible, dorsal view. (D) Mandible, ventral view. (E) Labium, ventral view. Scale bars = 0.1 mm.

FIGURE 29. Pilielmis shepardi Polizei & Barclay, 2019 (Coleoptera: Elmidae). Adult male. (A) Genitalia, ventral view. (B) Sternite VIII fused with ventrite V, dorsal view. (C) Tergite VIII, dorsal view. (D). Segment IX, ventral view.

FIGURE 30. Pilielmis shepardi Polizei & Barclay, 2019 (Coleoptera: Elmidae).Adult, female. (A) Ovipositor, ventral view. (B) Sternite VIII fused with ventrite V, dorsal view.

FIGURE 41. Paratypes of Pilielmis (Coleoptera: Elmidae). (A) Pilielmis murcia. (B) Pilielmis sara. (C) Pilielmis halia. (D) Pilielmis apama. (E) Pilielmis clita. (F) Pilielmis abdera. (G) Pilielmis shepardi. (A–F) Material housed at the NHMUK. (G) Material housed at MZSP. Scale bars = 0.5 mm.