Metaleptobasis inermis, Ellenrieder, 2013

Ellenrieder, Natalia Von, 2013, A revision of Metaleptobasis Calvert (Odonata: Coenagrionidae) with seven synonymies and the description of eighteen new species from South America , Zootaxa 3738 (1), pp. 1-155 : 44-45

publication ID	https://doi.org/ 10.11646/zootaxa.3738.1.1
publication LSID	lsid:zoobank.org:pub:77D1A6F6-C320-442B-AF31-83324E5EAF3B
persistent identifier	https://treatment.plazi.org/id/03E187ED-661D-FF94-D7A8-FD97E0D8FB87
treatment provided by	Felipe
scientific name	Metaleptobasis inermis
status	sp. nov.

Treatment

Metaleptobasis inermis View in CoL new species

Figs. 1m View FIGURE 1 ; 3m View FIGURE 3 ; 4m View FIGURE 4 ; 5m View FIGURE 5 ; 8m View FIGURE 8 ; 10m View FIGURE 10 ; 11m View FIGURE 11 ; 12m View FIGURE 12 ; 14e

Etymology. From Latin inermis (adjective), meaning 'unarmed', in reference to the unusually short and blunt male mesanepisternal horns which characterize this species.

Types. ( all *). Holotype ♂: BRAZIL, Pará State , Jacareacanga {6°16'S, 57°39'W}, vii 1969, F.R. Barbosa leg. [ UMMZ]; 2 ♂ paratypes: same data as holotype [ RWG]. GoogleMaps

Specimens examined. Total: 3 ♂.

Description of male holotype. Head. Labium and rear of head pale yellow; labrum pale yellowish blue with diffuse brown spotting and dark brown line along antero-basal margin; base of mandible pale yellowish blue; eyes brown, color in life unknown; remainder of head pale blue, with a pair of medio-lateral dark brown spots on anteclypeus, a dark brown stripe along anterior margin of postclypeus, black line over epicranial suture, black spots on epicranium as depicted in Fig. 1m View FIGURE 1 , and posterior margin of postocular region orange; postocular lobes rounded. Thorax. Color as described for genus, with mid-dorsal dark stripe black with metallic greenish-blue reflections, with sides straight and slightly widening posteriorly, as wide as 0.25 of mesepisterna width along medial portion ( Fig. 3m View FIGURE 3 ). Pronotum anterior lobe smooth; anterior and middle lobes of pronotum separated dorso-laterally by a groove; propleuron with a short c-shaped antero-dorsal crest and middle lobe of pronotum with a short c-shaped antero-ventral crest (c., Fig. 5m View FIGURE 5 ); pronotum posterior lobe trilobed, with medial lobe smoothly convex, and lateral lobes entire and smoothly convex, shorter than medial lobe ( Fig. 4m View FIGURE 4 ). Mesanepisternal horns bases separated, horns represented by sub-triangular bases, compressed antero-posteriorly, with rounded contour in posterior view, about as long as 0.50 of mesostigmal plate width, directed dorsally at an angle of about 75° with dorsum in lateral view. Wings hyaline, veins reddish brown; Pt sub-rectangular, with anterior and posterior sides longer than distal side, with membrane pale orange; 12 pnx in Fw and Hw. Abdomen. Postmortem background color pale yellowish blue on S1–6, pale yellow on S7–10; intersegmental membranes reddish brown; S1 with a brown dorso-posterior spot, and ventral carina of lateral tergum margined with black; dorsum of S2–10 reddish brown with a basal pale incomplete ring at anterior edge interrupted by dorso-longitudinal dark line, and with a small pale transverse spot near posterior margin on each side on S2–7, on S5–6 dark dorsal color posterior to pale transverse spot extended ventrally along sides of lateral terga, on S8 no pale basal ring but pale transverse spot near posterior margin; mediolongitudinal carina on sterna S2–6 reddish brown; cercus basal 0.30 pale reddish brown, remainder dark brown becoming black at apex; paraproct yellow, with distal half of external surface dark brown becoming black at apex. Genital lobe short, less than 0.50 of anterior hamule height, smoothly curved; posterior hamule digit-like and small, shortly surpassing ventral margin of genital fossa in lateral view; curvature of basal segment of genital ligula marked by a slight concave depression; genital ligula distal segment sub-quadrate, with ratio maximum width/length of 0.73, with apex with a shallow v-shaped concavity, lacking an ectal fold ( Fig. 8m View FIGURE 8 ). S10 medial portion of posterodorsal margin ( Figs. 10m View FIGURE 10 ; 11m View FIGURE 11 ; 12m View FIGURE 12 ) projected posteriorly, with a small u-shaped incision with sides thickened forming a dorsal prominence curved surrounding incision. Cercus in dorsal view ( Fig. 10m View FIGURE 10 ) sub-cylindrical, gradually curved medially and gradually narrowing to tip; tip depressed dorso-ventrally, ending on single small tooth directed medio-ventrally; ratio of cercus length to S10 maximum length in lateral view 1.27; ratio of cercus length to paraproct length in lateral view 0.83; paraproct sub-cylindrical, in lateral view ( Fig. 12m View FIGURE 12 ) of uniform width along medial portion and slightly narrowing to tip; distal 0.66 compressed with a medial concavity; tip pointed medially, with a single tooth.

Dimensions. Hw 21.9; abdomen 38.7; total length 46.6.

Variation in paratypes. Head. As in holotype but postocular lobes slightly angled in one paratype. Thorax. As in holotype but Pt membrane pale yellow in one paratype; pnx Hw 11–12. Abdomen. As in holotype but dark dorsal color posterior to pale transverse spot extended ventrally along sides of lateral terga on S4–6; ratio of male cercus length to S10 maximum length in lateral view 1.17–1.27; ratio of male cercus length to paraproct length in lateral view 0.82–0.85. Female unknown.

Dimensions. (n 3, including holotype): Hw 22.2 ± 0.6 [21.8–22.8]; abdomen 38 ± 0.6 [37.5–38.7]; total length 45.8 ± 0.8 [45.1–46.6].

Diagnosis. This is the only species of Metaleptobasis in which male horns are represented only by blunt prominences, and in which there is a c-shaped crest on the ventro-lateral area of middle lobe of pronotum opposite a c-shaped crest on the antero-dorsal area of propleuron (c., Figs. 4m View FIGURE 4 ; 5m View FIGURE 5 ). Among the species with a small digitlike male posterior hamule and dorsum of head with black color not extensive, M. inermis shares only with M. knopfi , M. leniloba , and M. selysi the combination of characters including anterior lobe of pronotum not projected postero-ventrally, middle lobe of pronotum lacking projections, propleuron lacking two subvertical crests, and horns directed antero-dorsally at an angle of 35°–90° with dorsum. Metaleptobasis inermis differs further from the last four species by the width of mid-dorsal stripe of pterothorax, about as wide as 0.25 of mesanepisterna at mid-length ( Fig. 3m View FIGURE 3 ; about as wide as 0.14–0.16 of mesanepisterna at midlength in M. leniloba , and about as wide as 0.33 of mesanepisterna at mid-length in M. knopfi and M. selysi , Figs. 3n–o, z View FIGURE 3 ), and by genital ligula distal segment sub-quadrate with a shallow u-shaped incision at tip ( Fig. 8m View FIGURE 8 ; vs. sub-quadrate with tip transverse in M. leniloba and sub-rectangular in M. knopfi and M. selysi , Figs. 83n–o, z).

Remarks. The female of M. inermis is still unknown, but I expect it to share with the male the short dorsal and ventral c-shaped crests laterally between anterior and middle lobes of pronotum and propleuron, the basic pattern of black markings on head dorsum, and mid-dorsal stripe width.

Habitat. Unknown.

Distribution. Pará State in Brazil ( Fig. 14e).