Mesoleptobasis cantralli Santos 1961

Figs. 3 b, 4b, 5b, c, 6a, 7b, 10b, 12b, 14b, 15b, 16b, 17b, 18b, 19a, 21

Mesoleptobasis cantralli Santos 1961: 197 –200, 202 (description of 3 and Ƥ); — Davies & Tobin 1984: 77 (catalog); — Bridges 1994: VII.43 (catalog); — Steinmann 1997: 288 (catalog); — Tsuda 2000: 39 (catalog); — Lencioni 2006: 160 (notes and illustrations from original description); — Heckman 2008: 393 (key and reproduction of illustrations from original description).

Types. Holotype (from Porto Velho, Rondônia, Brazil) in UMMZ (not examined).

Specimens examined. Total: 5 3, 8 Ƥ. Brazil, Rondônia State: 1 paratype 3, Porto Velho (8°46'S, 63°53'W), 22 ii 1922, leg. J.H. Williamson & J.W. Strohm (RWG); 1 paratype Ƥ, same but 24 iv 1922 (RWG); 1 paratype Ƥ, same but (UMMZ); 1 paratype 3, same but 27 ii 1922 (RWG); 1 paratype Ƥ, same but 0 4 v 1922 (RWG); 2 paratypes 3, 1 paratype Ƥ, same but 14 v 1922 (UMMZ); 3 paratypes Ƥ, same but 16 v 1922 (UMMZ); Amazonas State: 1 3, 1 Ƥ, Rio Uaupés, Taraquá (3°27'15''S, 62°51'5''W), 14 viii 1964, leg. A.B.M. Machado & Pereira (ABMM).

Diagnosis. Male prothorax with a medial bifurcate process with arms forming a transverse line between them (Fig. 4 b; shared with M. elongata and M. incus) and apices directed anteriorly (Fig. 3 b; shared with M. acuminata and M. cyanolineata); female prothorax lacking processes, with posterior margin slightly trilobate and medial lobe not surpassing lateral lobes posteriorly; lateral lobes not bent anteriorly (Figs. 5 b, c; shared with M. elongata). Costal side of FW pt longer than basal side, its posterior margin slightly convex in both sexes (Figs. 10 b, 12b; shared with M. cyanolineata, M. elongata, and M. incus). WF CuA relatively short (shared with M. elongata and M. incus), ending from one cell proximal to vein descending from subnodus (Fig. 10 b) to level of vein descending from subnodus (Fig. 12 b) in both sexes. Genital ligula in ectal view with distal margin deeply bifid and lacking lateral emarginations (Fig. 14 b; shared with M. cyanolineata, M. elongata, and M. incus); in lateral view with basal lobe sclerotized, long, pointed, and directed posteriorly, and dorsal margin of lateral lobe with a single small sclerotized spine (Fig. 15 b; shared with M. incus). Posterior margin of S10 projected medio-dorsally, with a pair of postero-lateral small lobe-like processes (Fig. 17 b, 19a; shared with M. elongata and M. incus). Male cercus lacking a membranous area dorsally (shared with M. cyanolineata, M. elongata, and M. incus), oblong, longer than wide (Figs. 17 b, 19a; unique), and usually armed at tip with a small externally recurved tooth (Figs. 17 b, 19a); in lateral view smoothly curved, with tip directed postero-ventrally (Fig. 18 b, shared with M. acuminata, M. elongata, and M. incus); paraproct slender and narrower than half of S10 height at base in lateral view (Fig. 18 b, shared with M. elongata and M. incus); base of paraproct usually with well developed thumb-like process (Figs. 17 b, 18b, 19a; shared with M. elongata), which can be vestigial. Ovipositor surpassing tip of cerci for a distance subequal to length of cerci (Fig. 16 b; shared with M. elongata).

Dimensions. Males (n 5; mean in parenthesis): Hw 17.0–18.0 (17.6); abdomen 33.0–36.0 (34.6); total length 39.0–41.0 (39.8). Females (n 8): Hw 18.5–20.0 (19.1); abdomen 30.0–34.0 (31.9); total length 35.0–39.0 (37.5).

Remarks. The pair of M. cantralli from Taraquá differs from the type series as follows: male lacks the small externally recurved tooth (as in Figs. 17 b, 19a), and the thumb-like process at the base of paraproct is vestigial; female middle lobe of hind lobe of pronotum is more strongly developed, but still does not surpass lateral lobes. Wing venation, shape of male pronotal process, male cerci, and morphology of hind lobe of female pronotum as well as length of ovipositor (surpassing tip of cerci for a distance subequal to length of cerci as in Fig. 16 b) match those for the type series and indicate that this pair is correctly placed here.

Distribution. Amazonas and Rondônia State in Brazil; sympatric with M. incus in the latter (Fig. 21).