Amnestus mendeli, Lis, Jerzy A. & Lis, Barbara, 2016

Lis, Jerzy A. & Lis, Barbara, 2016, Amnestus mendeli sp. n., the first burrower bug species (Hemiptera: Heteroptera: Cydnidae) recorded on Ascension Island, central Atlantic Ocean, Zootaxa 4126 (1), pp. 115-122 : 117-118

Amnestus mendeli new species

( Figs. 2 A–D, 3A–B, E–G)

Description. Body bicoloured; head, pronotum and scutellum castaneous or dark castaneous; antennae, tibial spines, costal margins, posterior parts of hemelytra, and hemelytral punctures brown; rostrum, legs, and hemelytral surface pale brown or yellowish brown.

Head ( Fig. 2 B). Clypeus slightly broadening apicad, distinctly longer than paraclypei and apically with four long sharpened pegs; clypeal surface impunctate, transversally striated with several striae making the clypeal surface uneven; paraclypei with distinct punctures over almost their entire surfaces, with small impunctate areas anteriorly, punctures colourless and only a little smaller than ocelli; paraclypeal margins with five pegs; eyes reddish brown or castaneous; ocelli yellow or yellowish brown; ocular index 2.4-2.6; ocellar index 4.0, interocellar distance approximately six times larger than the distance between the ocellus and the eye.

Prothorax. Pronotum almost rectangular in outline ( Fig. 2 A), its anterior margin almost straight, the lateral margins broadly rounded in the anterior half, and straight in the posterior half; callal areas almost impunctate, bearing several punctures only; transverse postcallal impression present, interrupted medially; posterior half of pronotal disc densely punctured with large coarse punctures, except for impunctate umbones; lateral parts of pronotal disc punctured with a few large coarse punctures bearing long, hair-like setae; lateral pronotal margins each with a submarginal row of 7-8 hair-like setae; propleuron castaneous, alutaceous; anterior and posterior convexities impunctate; prosternal carinae in profile approximately as high as labial segment II; transverse carina connecting the prosternal carinae uninterrupted medially ( Fig. 3 B, tc); additional longitudinal carina behind the transverse carina present ( Fig. 3 B, alc).

Mesothorax. Scutellum ( Fig. 2 A) with basal and lateral rows of large coarse punctures; scutellar disc almost evenly coarsely punctured, punctures as large as those forming lateral rows. Hemelytral shape typical of the genus with brown puncturation. Clavus with three parallel rows of coarse punctures ( Fig. 2 A); mesocorium with two rows of coarse punctures paralleling the clavo-corial suture and with several, almost evenly spaced, punctures in its posterior third; exocorium densely, almost evenly, punctured. Costal margins distinctly darker than the remaining part of the corium; membrane slightly translucent, whitish, surpassing the tip of the abdomen. Mesopleuron with evaporatorium typical of the genus. Legs pale brown or yellowish brown, tibial spines only a little darker; anterior femur ventrally near basal third with a stout, oblique, apically shallowly furcate spine ( Fig. 3 E), its length almost a half of femur diameter; subapical denticle on the ventral margin of the posterior femur strong and broad about a third as long as vertical femora diameter, bearing dorsally an apical finger-like process ( Fig. 3 F).

Abdomen. Sterna brown, alutaceous and punctate, punctures bearing long adherent, whistish, shiny, hair-like setae, especially numerous in the lateral third of sterna ( Fig. 3 G); paramere as in Fig. 2 C–D.

Measurements in mm (males only): body length: 2.22–2.24; body width: 1.16–1.18; pronotum length: 0.69- 0.74; pronotum width: 1.10–1.12; scutellum length: 0.44-0.46; scutellum width: 0.60-0.65; antennal segments: 0.12-0.13, 0.0 3, 0.17-0.20, 0.16-0.18, 0.19-0.20.

Type material. Holotype male: Ascension Island: Green Mountain, 743 m, Elliot’s Path, (Windy Corner), GPS 7.57S. 14.21W: 21 Nov. 2012, H. Mendel, [pitfall trap] (in the collection of the Natural History Museum, London, U.K.). Paratype male: same data as holotype (in the first author’s collection at the Department of Biosystematics, Opole University, Opole, Poland).

Etymology. The species is dedicated to Dr. Howard Mendel who has collected specimens of this new species and has inspired us to prepare this paper.

Differential diagnosis. The new species belongs to the group of species in which the transverse carina is as strongly developed as the prosternal carinae and is straight ( Fig. 3 B, tc); this group includes two Brazilian species, i.e., Amnestus lenkoi Froeschner, 1975 and Amnestus pequinus Froeschner, 1975 . In all other species of this genus, the carina is lower than the prosternal carinae and bowed or angled posteriorly ( Fig. 3 C, tc).

TABLE]. Diagnostic characters for A. lenkoi , A. pequinus anđ A. mendeli The new species can be easily separated from both A. lenkoi and A. pequinus in having the additional longitudinal carina behind the transverse carina on the prosternum ( Fig. 3 B, alc). Detailed differences among these three species are provided in the Table. However, characters for A. lenkoi and A. pequinus were taken from their original descriptions by Froeschner (1975), because our repeated requests to the curator of the collections in the Laboratório de Entomologia (Instituto Biológico, São Paulo, Brazil) for the loan of the types of both those species have been ignored.

Figures

FIGURE 2. Amnestus mendeli: (A) holotype male, body dorsal view; (B) holotype male, head, dorsal view (graphically darkened for better visibility of marginal pegs); (C – D) paramere, dorsal view (C), ventral view (D).

FIGURE 3. Amnestus mendeli, paratype male: (A) body ventral view; (B) prosternal carinae (transverse carina, tc: additional longitudinal carina behind the transverse carina, alc); (E) anterior femur (furcate spine indicated by the arrow); (F) posterior femur (subapical denticle indicated by the arrow); (G) lateral part of abdomen showing long adherent, shiny hair-like setae. Amnestus pusillus (C), Amnestus lenkoi (D, from Froeschner, 1975, modified): prosternal carinae (transverse carina, tc).