Pilielmis murcia 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 : 7-14

Pilielmis murcia Hinton, 1971

( Figs 1 , 3–6 , 41A )

Pilielmis murcia Hinton, 1971 a: 163 (original description).

Diagnosis. Body suboval; general coloration dark brown; antennae with uniform coloration, light brown; pronotum with yellowish-brown mark on anterior 1/3; 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 near the elytral suture); metathoracic wings absent; metaventrite with a pair of well-developed sublateral carinae. Male with phallobase 2x longer than wide; parameres reaching half the length of the penis, with a long seta at the apex, lateral margins without crenulations; penis 2x longer than wide; basolateral process 3x longer than wide.

Male redescription. Length: mean = 1.64 mm; width: mean = 0.74 mm (n = 5). Body suboval ( Figs 3A , 41A ); general coloration dark brown; elytra with yellowish-brown marks, mouthparts, antennae and legs light brown.

Head. Antennae with uniform coloration, light brown ( Fig. 3D ). Labrum ( Fig. 4A ): subrectangular, with lateral margins rounded; anterolateral margin with long setae; dorsal surface with short setae sparsely distributed along its entire length. Mandible ( Fig. 4C, D ): with lateral lobe rounded, slightly projected; molar area with a groove at base; posterolateral angle slightly rounded; condyle wider than long; longitudinal suture on disc. Maxilla ( Fig. 4B ): cardo longer than wide; stipe subtriangular; palpomere IV elongated, 2x longer than the previous one, with a rounded apex; galea with apical section subcylindrical, almost 2x longer than the basal one, lateral margin with apex rounded, with long, thin setae; lacinia subrectangular, 2x longer than wide, lateral margin with long setae on inner margin. Labium ( Fig. 4E ): mentum 4x wider than long, lateral margins rounded, with setae on each side, anterolateral angles pointed; postmentum subtriangular, wider than long; prementum subrectangular, with base and apex convex, 5x wider than long; ligula 2x wider than long, anterolateral region laterally projected, with short spines, ventral surface with two transverse rows of spines on disc; labial palpomere III with rounded apex.

Thorax. Pronotum ( Fig. 3A, C ) wider (0.56 mm) than long (0.41 mm); lateral margins convex, with crenulations; anterolateral and posterolateral angles acute; anterior region narrower than posterior region, with a yellowish-brown mark on the anterior 1/3; with a pair of straight, weakly elevated sublateral carinae; longitudinal impression on the disc deep and wide. Elytra ( Fig. 3A, C ) subparallel, 1.2x longer than wide (length = 0.95 mm; maximum width = 0.72 mm); apex rounded; 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). Scutellum cordiform. Metathoracic wings absent. Hypomeron 4x longer than wide. Prosternum ( Fig. 3B ) 0.55x longer than wide; anterior margin concave; anterolateral angles acute. Prosternal process ( Fig. 3B ) as wide as long; disc flat. Mesoventrite ( Fig. 3B ) wider (0.36 mm) than long (0.14 mm); posterior margin truncated between the mesocoxae; cuticle similar to prosternum. Metaventrite ( Fig. 3B ) with a pair of well-developed sublateral carinae on disc; disc flat; surface with few setae; lateral margins covered by tomentum. Hind legs ( Fig. 3B ). Trochanter 2x longer than wide. Femora 3x longer than wide. Tibiae 6x longer than wide. Apical tarsomere 1.3x longer than the basal ones combined. Claws large and slender, with a tooth near base.

Abdomen. Ventrite I without tomentum, ventrites II–V with tomentum; intercoxal process of ventrite I depressed; ventrite V with short setae ( Fig. 3B ). Tergite VIII ( Fig. 5D ) almost as long as wide; posterior margin rounded; surface with thin setae, spines and microspines. Sternite VIII ( Fig. 5B ) 3.5x wider than long; surface with microspines (more abundant near the apex); with setae near the apex; anterior median projection 2x longer than the sternite body length. Segment IX ( Fig. 5C ) subtriangular, with rounded apex; anterolateral margin with sensory pores, and microspines and setae. Genitalia ( Fig. 5A ). Phallobase 2x longer than wide, 1.5x longer than the penis. Parameres reaching half the length of the penis; base wider than apex; apex rounded, with a long seta; lateral margins without crenulations. Penis 2x longer than wide; apical region rounded; lateral margin sinuous; surface with sensory micropores throughout the area; basolateral process 3x longer than wide.

Female redescription. Externally similar to male. Length: mean = 1.47 mm; width: mean = 0.71 mm (n = 5). Tergite VIII ( Fig. 6C ) wider than long, posterior margin rounded; surface with long setae (more abundant on anterior region) and short setae, spines and microspines. Sternite VIII ( Fig. 6B ) 2x wider than long; anterior median projection 2x longer than the sternite body length; posterior margin with setae; surface with short setae and microspines. Ovipositor ( Fig. 6A ): valvifer 2.1x longer than the coxites; surface with sensory micropores in the apical 1/5. Apical coxite 1.9x longer than wide, 1.7x longer than the basal one. Stylus slightly curved, measuring 1/4 the length of the apical coxite; apex with short setae.

Intraspecific variation. Elytra with a pair of light-brown marks at the base; in some specimens the apical mark may extend to the anterior 3/4.

Comparative notes. Pilielmis murcia resembles P. shepardi based on the body suboval, by the 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. However, both species can be easily distinguished as follows: in P. murcia the general coloration is dark brown; the metaventrite has a pair of well-developed sublateral carinae on the disc; the male has the parameres reaching half the length of the penis, with a long seta at the apex, and the apical region of the penis is rounded. On the other hand, P. shepardi has the general coloration black, the carinae are absent on the metaventrite disc; ventrite V and sternite VIII are fused; the male has the parameres reaching 3/5 the length of the penis, without setae at the apex, and the apical region of the penis is subtriangular.

Distribution: French Guiana (St. Laurent du Maroni) and Brazil (Amazonas, Mato Grosso *, and Pará) ( Fig. 1 ).

Material examined. Paratypes: Brazil, Pará, Belém, ix.1937, H.E. Hinton (2 in NHMUK); Amazonas, Manaus, ix.1937, H.E. Hinton (1 in NHMUK) . Additional material. BRAZIL. Amazonas: Manaus, BR 174 - Km 56, 25.v.2008, 02°35′57.3′′ S, 60°13′01.2′′ W, Azevedo et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (3 in INPA) ; Km 25, Ramal Quinta da Boa Esperança , 27.v.2008, 02°44′42.7′′ S, 60°00′00.6′′ W, Azevedo et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (2 ♂ in INPA) ; 11.xi.2008, 02°44′42.7′′ S, 60°00′00.6′′ W, Neiss et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (1♂ in INPA) ; 27.v.2008, 02°44′42.7′′ S, 60°00′00.6′′ W, Hamada et al. leg., Pinedo-Garcia & Polizei det. 2020 (pin) (4♂ and 4♀ in INPA) ; AM 240 -km 13, Reserva Ducke, AM-010-km 26, Bolivia steam, 23.iv.2008, 02°59′14.5′′ S, 59°56′30.5′′ W, Azevedo et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (1♂ in INPA) ; Presidente Figueiredo, km 24, Sítio Seu José , 20.iv.2008, 02°44′42.7′′ S, 60°00′00.6′′ W, Hamada et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (2 ♂ in INPA) ; AM 240 -km 13, Sítio da Maroca , 23.iv.2008, 02°00′54.4′′ S, 59°51′34.4′′ W, Hamada et al. leg., Pinedo-Garcia & Polizei det. 2020 (pin) (3 in INPA) ; Rio Preto da Eva, AM 010 - Km 113, Ramal Casa Branca , Km 4.5, 11.iv.2008, 02°47′24.4′′ S, 59°30′11.6′′ W, Azevedo et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (3♂ in INPA) . Mato Grosso: Barra do Garça, Corrente River , 12.vii.2012, 15°35′42.8′′ S, 52°22′35.8′′ W, Hamada et al. leg., Pinedo-Garcia & Polizei det. 2020 (alcohol) (1♀ in INPA) . Pará: Jacareacanga , xii.1968, Alvarenga et al. leg., Polizei det. 2018 (pin) (64 in DZUP) .

Figures

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

FIGURE 3. Pilielmis murcia 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 4. Pilielmis murcia 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 5. Pilielmis murcia Hinton, 1971 (Coleoptera: Elmidae). Adult, male. (A) Genitalia, ventral view. (B) Sternite VIII, dorsal view, with the anterior region highlighted. (C). Segment IX, ventral view. (D) Tergite VIII, dorsal view.

FIGURE 6. Pilielmis murcia Hinton, 1971 (Coleoptera: Elmidae). Adult, female. (A) Ovipositor, ventral view. (B) Sternite VIII, dorsal view, with the anterior 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.