Belostoma lanemeloi Ribeiro & Ferrari, 2023

Ribeiro, Jose R. I. & Ferrari, Augusto, 2023, Phylogenetic analysis of the Belostoma plebejum group sensu Nieser (Insecta, Hemiptera, Belostomatidae): the effect of adding continuous characters on its accuracy, Arthropod Systematics & amp; Phylogeny 81, pp. 1-34 : 1

Belostoma lanemeloi Ribeiro & Ferrari sp. nov.

Fig. 4A-E

Type locality.

Pirapora Municipality, Minas Gerais State, Brazil.

Diagnosis.

Body narrow and long. Knobshaped ‘druckknopf’ on mesepimeron rounded, as wide as long. Arms of phallotheca diverging apically in dorsal view; lateral margin of diverticulum of phallossoma strongly curved mesally, in dorsal view; width of diverticulum as long as its length, in ventral view.

Description.

Male. Body length: 14.4 mm; greatest width of body: 6.3 mm. Female. Body length: 13.7 mm; greatest width of body: 6.0 mm. Body whitish brown. Head.-Anterior frontogenal suture (anteclypeus-maxillary plate suture) shorter than posterior frontogenal suture (anteclypeus-loral plate suture); anteoculus slightly shorter than interoculus (from 0.89 to 0.94 times); length of visible segment I of rostrum from 0.78 to 0.88 times the length of visible segment II. Thorax.-Sclerite 1 of distal median plate becoming broader medially, as wide as long; notch or indentation much more poorly developed along its basilateral margin, which is somewhat concave (Fig. 4A ); apical portion with lobed process poorly developed, rounded; posterior portion articulated with veins 1A and 2A bearing process directed posteriorly shorter than half of the longitudinal length of sclerite 1; process not indented apically and approximately straight; knobshaped ‘druckknopf’ on mesepimeron rounded, as wide as long (Fig. 2A ); prosternal carina poorly elevated, rectangular, quite pointed anteriorly, with its anterior margin smoothly curved, not projected anterad in lateral view; apex without tubercles (Fig. 4B ). Abdomen.-Pilosity covering about one third of connexivum, poorly developed on penultimate visible segment. Male genitalia (Fig. 4C-E ).-Arms of phallotheca diverging apically, shorter than its anterior region (base of phallosoma), not covering sides of ventral diverticulum in dorsal view. Ventral diverticulum curved, rounded apically in lateral view; apical margin smoothly concave, with prominence in dorsal view; lateral margins slender, not thickened, curved at mid-length, directly laterally in dorsal and ventral views. Width of diverticulum as long as its median length in ventral view. Ventroapical protuberance not distinctly produced in lateral view, approximately triangular in ventral view.

Remarks.

Belostoma lanemeloi sp. nov. appears closely related to the species of the B. pygmeum group, as well as B. plebejum . Members of the B. pygmeum group share with the new species the posterior portion of the sclerite 1 of the distal median plate, articulated with veins 1A and 2A, bearing a short process directed posteriorly. The new species also shares with B. nicaeum and B. pygmeum a sclerite 1 that is somewhat straight along its basilateral margin, without any notch or indentation. Belostoma plebejum instead shares with B. lanemeloi sp. nov. a rounded knobshaped ‘druckknopf’. The new species, however, can be distinguished from the species of the B. pygmeum group by the body being narrower and longer. Additionally, the new species may be easily mistakenly keyed to B. plebejum when using either Estévez and Polhemus’ (2007) or Ribeiro and Alecrim’s (2008) keys to the B. plebejum group because of the considerable uniformity in body structures and the smooth genitalic variation among the species of B. plebejum group s.l. In fact, B. lanemeloi sp. nov. shares with B. plebejum slender, not thickened, lateral margins of the ventral diverticulum, and a body size that is more than 13.0 mm long. The new species can be distinguished from B. plebejum by the arms of the phallotheca diverging in dorsal view and by the width of diverticulum as long as its median length in ventral view.

Etymology.

The specific epithet is dedicated in honour of Dr Alan Lane de Melo (Universidade Federal de Minas Gerais, Brazil) for his contributions to the study of Brazilian giant water bug taxonomy.

Material examined.

Holotype. BRAZIL • 1 ♂; Minas Gerais State, Pirapora Municipality ; 17°20.40'S, 44°55.80'W; Nov. 1975; M. Alvarenga leg.; J.R.I. Ribeiro det.; AMNH .- Paratype. BRAZIL • 1 ♀; same data as for holotype .

Figures

Figure 2. Mesepimeron and part of wing-to-body coupling mechanism. Part of the ' Druckknopf ' system component, located in the thorax. The system allows for the complete coupling of hemelytra to the dorsum. Character 27 was proposed by studying only the complementary structure of the apparatus, located in mesepimeron, not that on the wing apparatus. A Knobshaped ' Druckknopf ' system rounded, as long as wide B knobshaped ' Druckknopf ' system piriform, longer than wide.

Figure 4. Belostoma lanemeloi Ribeiro & Ferrari, sp. nov. and B. nieseri Ribeiro & Ferrari, sp. nov. A - E Male holotype of B. lanemeloi sp. nov. from Minas Gerais State, Brazil; F - J Male holotype of B. nieseri sp. nov. from Mato Grosso State. A Sclerite 1 of distal median plate of hindwing; B prosternal carina (lateral view); C - E male genitalia: phallosoma (phallotheca, dorsal arms, and diverticulum); C dorsal view; D ventral view; E lateral view; F sclerite 1 of the distal median plate of the hind wing; G prosternal carina (lateral view); H - J male genitalia: phallosoma (phallotheca, dorsal arms, and diverticulum); H dorsal view; I ventral view; J lateral view.