Pilielmis clita 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 : 31-36

Pilielmis clita Hinton, 1971

( Figs 1 , 19– 22 , 41E )

Pilielmis clita Hinton, 1971 a: 165 (original description).

Diagnosis. Body subparallel; general coloration yellowish-brown; antennae with uniform coloration, yellowish-brown; pronotum with anterior 1/3 lighter; pronotum with golden setae; elytra with apex lighter; prosternal process longer than wide. Male with phallobase 2.3x longer than wide; parameres reaching approximately half the length of the penis; penis 3x longer than wide, with subtriangular apical region and straight lateral margins; basolateral process 3.5x longer than wide.

Male redescription. Length: mean = 1.73 mm; width: mean = 0.68 mm (n = 5). Body subparallel ( Figs 19A , 41E ); general coloration yellowish-brown.

Head. Antennae with uniform coloration, yellowish-brown ( Fig. 19D ). Labrum ( Fig. 20A ) subrectangular, with lateral margins rounded; anterolateral margins with long setae; dorsal surface with short and sparse setae. Mandibles ( Fig. 20C, D ): lateral lobe rounded; posterolateral angle slightly rounded; condyle subrectangular. Maxilla ( Fig. 20B ): cardo subtriangular, lateral margin sinuous; stipe subtriangular; palpomere IV elongated, 2x longer than the previous one, with apex truncated; galea with apical section subcylindrical, 2x longer than the basal one, lateral margin rounded, apex truncated, with long setae; lacinia subrectangular, 2x longer than wide, lateral margin with long setae. Labium ( Fig. 20E ): postmentum subtriangular; prementum subrectangular, 2.5x wider than long; ligula subrectangular, 2x wider than long, anterolateral margins with short spines; gula subrectangular, 2x wider than long, lateral margins sinuous, anterolateral angles rounded; labial palpomere III with truncated apex.

Thorax. Pronotum ( Fig. 19A ) approximately as wide (0.49 mm) as long (0.47 mm); lateral margins sinuous, with crenulations; anterolateral and posterolateral angles acute; anterior 1/3 lighter; with a pair of sinuous, strongly raised sublateral carinae; longitudinal impression on the disc shallow; with many golden setae. Elytra ( Fig. 19A ) subparallel, approximately 2x longer than wide (length = 1.14 mm; maximum width = 0.66 mm); apex rounded; apical region lighter. Scutellum suboval. Metathoracic wings present ( Fig. 21E ). Hypomeron 6x longer than wide, anterior margin slightly rounded. Prosternum ( Fig. 19B ) 0.55x longer than wide; anterior margin rounded; anterolateral angles acute. Prosternal process ( Fig. 19B ) longer than wide; anterior margin rounded. Mesoventrite ( Fig. 19B ) wider (0.23 mm) than long (0.10 mm); anterior margin sinuous, convex on disc; posterior margin truncated between the mesocoxae; cuticle similar to prosternum. Metaventrite ( Fig. 19B ) with an oval depression on basal half; anterior margin sinuous between the mesocoxae; discrimen conspicuous on basal half. Hing legs ( Fig. 19B, C ). Trochanter 2x longer than wide. Femora 3.5x longer than wide. Tibiae approximately 5x longer than wide. Apical tarsomere 1.5x longer than the basal ones combined. Claws large and slender, with a tooth near base.

Abdomen. Ventrites I–IV without tomentum on disc; ventrite V with golden setae ( Fig. 19B ). Tergite VIII ( Fig. 21C ) 1.6x wider than long; posterior margin rounded; surface with short setae, spines and microspines (more abundant on the basal 1/3). Sternite VIII ( Fig. 21B ) 3x wider than long; anterior median projection 1.6x longer than the sternite body length. Segment IX ( Fig. 21D ) subtriangular, with rounded apex; anterior margin with sensory pores and short setae. Genitalia ( Fig. 21A ). Phallobase tubular, constricted anteriorly; 2.3x longer than wide; 1.2x longer than the penis. Parameres 2.5x longer than wide, reaching approximately half the length of penis; base wider than the apex; lateral margins without crenulations. Penis 3x longer than wide, with apical region subtriangular; lateral margins straight; surface with sensory micropores more abundant anteriorly; basolateral process 3.5x longer than wide.

Female redescription. Externally similar to male. Length: mean = 1.72 mm; width: mean = 0.74 mm (n = 5). Tergite VIII ( Fig. 22C ) wider than long, posterior margin rounded; surface with setae (more abundant on anterior region), spines and microspines. Sternite VIII ( Fig. 22B ) 2x wider than long; anterior median projection 1.6x longer than the sternite body length; posterior margin with setae; surface with shorter setae and microspines. Ovipositor ( Fig. 22A ): valvifer 2x longer than the coxites; posterior margin with sensory micropores. Apical coxites 1.7x longer than wide, 1.3x longer than the basal one. Stylus slightly curved, measuring approximately 1/3 the length of the apical coxite.

Intraspecific variation. In some females, the posterolateral projections of sternite VIII can be less pointed.

Comparative notes. Among the Pilielmis species, P. clita resembles P. abdera based on the body subparallel, antennae with uniform coloration (yellowish), pronotum covered by many golden setae, elytra without humeral color marks, and penis with subtriangular apex. However, P. clita can be distinguished from this species by the lighter coloration, prosternal process longer than wide, hypomeron with anterior margin slightly rounded, femora uniformly colored, and the male genitalia with the phallobase 2.3x longer than wide, and penis 3x longer than wide with the basolateral process 3.5x longer than wide. Pilielmis abdera has the prosternal process as long as wide, hypomeron with the anterior margin slightly narrow, femora with apical region darker and the male genitalia with the phallobase 1.8x longer than wide and penis 4x longer than wide, with basolateral process 6x longer than wide.

Distribution: Brazil (Amazonas, Mato Grosso *, and Pará) and Peru * ( Fig. 1 ).

Material examined. Paratypes: Brazil, Amazonas, Manaus, ix, 1937 H.E. Hinton (2♂ and 2♀ in NHMUK) . Additional material. BRAZIL. Amazonas: Manaus, Tupé beach, Pegadão , 24-25.x.2009, 03°53′10′′ S, 60°28′36′′ W, Pes et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (4 ♂ and ♀ in INPA) . Pará: Paragominas , 20.vii.2011, 03°08′49.9′′ S, 47°34′30.0′′ W, Brito et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (10♂ in INPA) . Mato Grosso: Apiacas, Alluvial Forest, Bruno stream, Hamada et al. leg., 04.v.2008, Pinedo-Garcia & Polizei det. 2020 (pin) (1 ♂ and 1♀ in INPA) ; PERU. Loreto: Iquitos, Quistococha stream, 12-13.vii.2019, 3°48.45′ S, 73°20.38′ W, Pinedo-Garcia & Saavedra-Garcia leg., Pinedo-Garcia det. 2021 (alcohol and laboratory slide), (3♂, 2♀ in INPA) ; Madre de Dios, Tambopata, Puerto Maldonado , 21.vi.1989, 12°33′ S, 69°03′ W, camp. Ashe et al. leg., Pinedo-Garcia & Polizei det. 2020 (pin) (1 in SEMC) .

Figures

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

FIGURE 19. Pilielmis clita Hinton, 1971 (Coleoptera: Elmidae). Adult, male, habitus. (A) Dorsal view. (B) Ventral view. (C) Lateral view. (D) Front view. Scale bars = 0.5 mm.

FIGURE 20. Pilielmis clita Hinton, 1971 (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 21. Pilielmis clita Hinton, 1971 (Coleoptera: Elmidae). Adult, male. (A) Genitalia, ventral view. (B) Sternite VIII, dorsal view. (C) Tergite VIII, dorsal view. (D) Segment IX, dorsal view. (E) Metathoracic wing.

FIGURE 22. Pilielmis clita Hinton, 1971 (Coleoptera: Elmidae).Adult, female. (A) Ovipositor, dorsal view, with partial region of the coxites highlighted. (B) Sternite VIII, dorsal view, with the posterolateral region highlighted. (C) Tergite VIII, 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.