Dinidor jograziae, López & Carrenho & Schwertner, 2021

López, Guilherme E. L., Carrenho, Renan & Schwertner, Cristiano F., 2021, Description of a new species of Dinidor Latreille (Hemiptera: Dinidoridae) from the Brazilian Amazon Rainforest, and new records of D. saucius Stål, Zootaxa 4958 (1), pp. 654-662 : 655-658

Dinidor jograziae sp. nov.

( Figs. 1–8 )

Type material. Holotype (♂): S. Gabriel [Municipality of São Gabriel da Cachoeira], Rio Negro , Amaz. [State of Amazonas], 29.XI.1927, J. F. Zikán col., Coleção J. F. Zikán, 80688, CEIOC . Paratype: 1♀, same label as the holotype, CEIOC .

Etymology. The species is named in honour of Prof. Dr. Jocélia Grazia, for her extensive and decisive contributions to the knowledge of the Heteroptera fauna of the Neotropics. Also, we recognize her for being a kind, inspiring and vivid mentor to several generations of taxonomists, including ourselves. Her legacy will always be a part of our lives.

Diagnosis. Dinidor jograziae sp. nov. can be recognized by the following combination of characters: mandibular plates relatively short, truncate to rounded at apex, and not contacting each other in front of clypeus; lateral margins of mandibular plates sinuate; first antennal segment exceeds the apex of mandibular plates; rostrum only reaching the anterior margins of mesocoxae; pronotum with a medial suffused red stripe; anterolateral margins of pronotum straight, not emarginate; humeral angles rounded; scutellum with a medial ocher spot along basal margin, and a red/reddish brown suffused patch on the apical tip, reaching the middle of sternite IV, much shorter than half the length of the abdomen; lateral margins of the scutellum sinuate, narrowing posteriorly, apex acuminate; hemelytral membrane dark brown, with darker, reticulate veins; thoracic sterna, coxae and trochanter suffused in reddish brown; connexiva mostly red, with large black spots on anterior and posterior margins; ventral abdomen mostly black, suffused medially with reddish-brown band close to the posterior margin, and a semi-circular red marking on the lateral margin of each urosternite.

Description. Measurements (in mm, ♂ / ♀). Total length 14.4/17.0; head length (along midline from base to an imaginary line connecting apices of mandibular plates) 1.6/1.7; head width (measured across eyes) 2.2/2.4; interocular distance 1.7/1.9; interocellar distance 0.8/0.9; lengths of antennal segments: scape 0.8/1.05, pedicel 1.8/2.1, basiflagellum 1.4/1.6, distiflagellum 2.4/2.7; labial segments lengths: AI 1.0/1.0, AII 1.2/1.1, AIII 0.7/0.8, AIV 0.6/0.7; pronotum length (along midline) 3.9/4.5; pronotum width (at humeral angles) 6.9/8.3; scutellum length (along midline) 3.8/4.1; scutellum width (at base) 4.0/5.0; abdomen width 8.2/10.1.

General body outline and colour (figs. 1, 2). Elongate, much longer than wide, oval in shape. Abdomen, at its widest point, wider than pronotum. General colour of body black, with many structures (described below) red, and some spots yellow/ocher; venter black, with median portion of the sternites III–VI brown. Lateral paired trichobothria located within large, round, orangish-yellow calluses located on sternites III–VII. Entire body (including legs and antennae) covered with fine yellowish bristles.

Head (fig. 3). Relatively short, 0.4 times length of pronotum; wider than longer, width about 1.4 times length. Rugose, mainly on dorsal portion, and even more prevalent on mandibular plates (mp); a few yellow bristles present. Mandibular plates 1.5 times longer than clypeus, apex round to truncate, coming close to each other but not touching at apex; lateral margins of mandibular plates sinuate. Bucculae anteriorly rounded, extending almost to apex of head; posteriorly, bucculae nearly reaching to middle of compound eyes. Compound eyes rounded, positioned laterally, slightly pedunculate, protruding. Ocelli rounded, red to reddish brown, located much closer to compound eyes than to each other. Antennae 4-segmented; first 3 segments concolourous with head; 4th segment mostly ochraceous, with a very small portion of its base concolourous with other segments. Antennal segments I and IV cylindrical; segments II and III prismatic, grooved on dorsal and ventral surfaces. First antennal segment exceeds apex of head; length of segments ratio: IV>II>III>I. Antenniferous tubercles ventrally positioned, partially obscured by compound eyes and mandibular plates. Rostrum 4-segmented, reaching anterior margins of mesocoxae; segment II longest; segment I reaches base of head, longer than segment III, segment IV shortest.

Thorax (figs. 1–3). Pronotum trapezoidal, with anterior angles slightly projecting anteriorly. Anterior margin of pronotum concave; anterolateral margins straight, not emarginate; humeral angles rounded. General colour of pronotum black, with lateral margins and a medial stripe suffused red; stripe thin on anterior half of its length, becoming wider posteriorly. Scutellum subtriangular, lateral margins slightly sinuate, narrowing posteriorly, with a small expansion at apex, acuminate; scutellum reaching middle of sternite IV, much shorter than half length of abdomen. Scutellum mostly of same colour as body, with an ochraceous spot at midline of basal margin, and a red/reddish brown suffused patch at apex. Meso- and metasternum with a distinct, deep, medial groove, narrowing between mesocoxae, suffused in reddish brown (along with coxae and trochanters).

Hemelytra (fig. 1). Corium longer than scutellum, claval comissure absent; membranes reaching posterior margin of urosternite VII. Corium mostly black, costal margins red, concolorous with lateral margins and medial stripe of pronotum. Membranes dark brown, with many thick, darker veins, forming a reticulate pattern with many closed cells.

Legs (fig. 2). Forecoxae much closer to each other than mesocoxae and metacoxae; distance between mesocoxae subequal to distance between metacoxae. Tibiae grooved dorsally; foretibiae slightly depressed laterally. Coxae and trochanters reddish brown, remaining leg segments black. Foretibial apparatus present; tibial combs present. Tarsi 3-segmented, claws depressed laterally, without bristles. Pulvilli differentiated into basi- and distipulvilli.

Abdomen (figs. 1, 2, 4). Connexiva mostly exposed, red with large black spots on anterior and posterior margins of each connexival segment; posterolateral angles slightly projected. Spiracle II slightly exposed in male, totally covered by urosternite III in female. Spiracles III–VII exposed, located laterally on urosternites. In females, spiracle exposed on laterotergites VIII. Pseudo-sutures present on each urosternite, posteriorly to spiracles. A pair of trichobothria present on segments III–VII, located on a large, round, orangish-yellow callus, contiguous with pseudo-sutures, oriented diagonally with spiracles of corresponding segments. Abdominal venter mostly black, suffused medially with reddish-brown band close to posterior margin, a semi-circular, red marking on lateral margin of each urosternite.

Male genital capsule (figs. 5–8). External opening dorso-posterior; outline of posterior rim oval, wider than long; dorsal rim (dr) folded inwards medially over segment 10 (X), rugose; ventral rim (vr) emarginate, slightly undulated medially, almost straight; cuplike sclerite with a small projection (csp). Parameres (p) each with apical border regular, nearly straight, thin, covered with many yellowish bristles.

Female genital plates (figs. 2, 4). Gonocoxites 8 (gc8) subtriangular, wider than long, shorter than laterotergites 8 (lt8); mesial margins juxtaposed, posterior margins slightly convex. Laterotergites 8 triangular, posterior margins slightly concave; spiracles (s) located basally. Laterotergites 9 (lt9) oblong, longer than wider, apices rounded; mesial margins juxtaposed basally, straight, divergent towards apices; posterior margins suffused with red; surface with a small depression laterally. Segment 10 (X) visible ventrally between laterotergites 9.

Comments. Dinidor jograziae is easily separated from D. braziliensis and D. impicticollis by the unique body colour patterns of these two species; that is, D. braziliensis is mostly brown in colour, D. impicticollis is the only species with the pronotum entirely black without any spots or stripes of a different colour. In turn, D. jograziae has the same body colour pattern of the remaining described species of Dinidor : mostly black with a red to reddish-brown stripe present along the lateral margins of the pronotum, which extends to the costal margins of the hemelytra.

The new species differs from the remaining species ( D. mactabilis , D. pulsator , D. rufocinctus and D. saucius ) in several aspects including colouration pattern, shape and proportion of the mandibular plates, proportional length of the rostrum, shape of the lateral margins of the pronotum and humeral angles, length and general outline of the scutellum, and general outline of the ventral rim of the pygophore, among others ( Table 1 ).

Some of the major differences we found between D. jograziae and the three similar species found in northern South America ( D. mactabilis , D. pulsator and D. rufocinctus ) include characteristics such as size and the general body outline. Two species, D. mactabilis and D. rufocinctus , are larger than D. jograziae , the anterolateral margins of the pronotum are slightly convex and emarginate, the humeral angles are obtusely rounded, and the connexiva are narrowly exposed, giving the body outline a more elongate aspect. Although D. pulsator is similar in size and has rounded humeral angles, the description provided by Durai (1987) highlights the anterolateral margins of pronotum being strongly reflexed (“tilted upwards”), and the connexiva is narrowly exposed. The new species is smaller, the anterolateral margins of the pronotum are straight, not reflexed, and the connexiva is largely exposed. The colouration pattern of the connexiva also differs between them; for example in D. mactabilis , D. pulsator and D. rufocinctus , it is mostly red to orange-brown coloured with small black or brown spots on the intersegments, while in D. jograziae , it is red with large black spots on both the anterior and posterior margins of each segment.

Dinidor jograziae and D. saucius are similar in size, and they share an oval body outline with the humeral angles rounded, and the connexiva largely exposed. Both species also share the coloured pattern of the connexiva. However, D. saucius has the mandibular plates spatulate (truncate in D. jograziae ), with lateral margins deeply sinuate (only slightly sinuate in D. jograziae ), pronotum with the anterolateral margins slightly concave (straight in D. jograziae ), scutellum with the lateral margins deeply sinuous and apex rounded (lateral margins sinuate and apex acuminate in D. jograziae sp. nov.). Also, although variable in width, the median red stripe on the pronotum is always wider and more conspicuous in D. saucius . Additionally, D. saucius seems to be restricted to southeastern Brazil (see discussion below), while D. jograziae appears to be endemic to the Amazon region ( Fig. 9 ).

Distribution. BRAZIL: Amazonas (São Gabriel da Cachoeira).

Figures

FIGURE 9. Map of South America showing the distributional records for D. jograziae (red dot) and D. saucius (yellow dots).

FIGURES 1–2. Habitus of Dinidor jograziae sp. nov. 1, dorsal view; 2, ventral view (Scale bar = 2 mm)

FIGURES 3–8. Dinidor jograziae 3, dorsal view of the head (male); 4, genital plates (ventral view); 5, terminal abdomen (posterior view); 6-8 pygophore (dorsal, ventral, and lateral views, respectively). csp, cup-like sclerite projection; dr, dorsal rim; gc8, gonocoxites 8; lr, lateral rim; mp, mandibular plates; lt8, laterotergites 8; lt9, laterotergites 9; pa, paramere; s, spiracle; VII, urosternite VII; vr, ventral rim; X, segment X.