Platystigma pronoti

Machado, Angelo B. M. & Soldati Lacerda, Déborah S., 2017, Revalidation of Platystigma Kennedy, 1920, with a synopsis of the quadratum species group and the description of three new species (Odonata: Pseudostigmatidae), Zootaxa 4242 (3), pp. 493-516: 501-502

publication ID

https://doi.org/10.11646/zootaxa.4242.3.4

publication LSID

lsid:zoobank.org:pub:4FCEE7BF-C562-4550-9D42-F7B86678DBBB

persistent identifier

http://treatment.plazi.org/id/891587DD-FFCE-9B28-D2A2-FB61FB5A60A8

treatment provided by

Plazi

scientific name

Platystigma pronoti
status

 

Platystigma pronoti   (Sjӧstedt, 1918) n. comb.

Figures 12 View FIGURES 8 – 13 , 18 View FIGURES 14 – 19 , 33–36 View FIGURES 33 – 36

Sjӧstedt (1918: 31); Davies & Tobin (1984: 57); Garrison & Ellenrieder (2016: 20); Machado (1992: 19); Bridges (1994: 39); Tsuda (2000: 58); Machado, Drummond & Martins (2005: 96); Heckman (2008: 205); Garrison, Ellenrieder & Louton (2010: 391); Schorr & Paulson (2016); Machado & Lacerda (2016: 63).

Material examined. Holotype ♀: Brazil, Espírito Santo (no further information available)   . Holotype deposited in the NHMS.

Diagnosis. Head with dorsum black and orange-white spots anteriorly and another medially to antennae base. Pronotum dark brown with pair of pale yellow stripes anteriorly and laterally to middle lobe. Border of medial and apex of lateral portions of posterior prothorax lobe pale yellow. Median portion straight, separated from lateral portions by deep incision at each side ( Fig. 12 View FIGURES 8 – 13 ); lateral portions with apex rounded ( Fig. 12 View FIGURES 8 – 13 ). Mesepisternum ( Fig. 18 View FIGURES 14 – 19 ) black with antehumeral grayish-yellow stripe occupying whole extension of sclerite. Mesepimeron dark brown with grayish-yellow stripe not reaching lower part of sclerite. Metapleuron ( Fig. 18 View FIGURES 14 – 19 ) whitish yellow with black stripe adjacent to metapleural suture occupying dorsal ¾ of sclerite. Venter of pterothorax whitish yellow, with narrow middle dark stripe occupying its anterior ½. It is impossible to know whether this stripe reaches the posterior part of the venter, because it is damaged. Supplementary tooth of tarsal claws absent. Wings dominantly hyaline with apical area milky-white reaching a row of cells posterior to RP1. Pseudostigma in both wings weakly indicate pale yellow color ( Figs. 33, 35 View FIGURES 33 – 36 ). At high saturation, the color of apical area changes; the white color becomes pale blue and the pseudostigma appears very evident, yellow, with six cells in Fw and eight in Hw ( Figs. 34, 36 View FIGURES 33 – 36 ). Costal vein becomes orange and RA to RP1 yellow ( Figs. 34, 36 View FIGURES 33 – 36 ). Abdomen dominantly brown. Cercus dark, with apex rounded. Ovipositor (stylus lacking) reaching posteriorly about level of hind border of S10.

Measurements (mm): Hw 40. Abdomen 54.

Male: unknown.

Remarks. Mecistogaster pronoti   is transferred here to Platystigma   based on its small size, absence of supplementary tooth of tarsal claw and presence of pale apical areas on the wings. The species was described by Sjӧstedt (1918) based on a single female specimen from the state of Espírito Santo, Brazil, and has never been found again. According to Heckman (2008), “ M. pronoti   is a rare or unrecognized species.” The holotype of P. pronoti   has been recently redescribed and illustrated by Machado & Lacerda (2016), thus allowing its easy identification. The main character separating P. pronoti   from the other Platystigma   species is the peculiar form of the hind prothoracic lobe, whose median portion is clearly separated from the lateral ones. P. pronoti   has been listed as Critically Endangered in Brazil’s, Portarias MMA n o 444/445 (2014) and IUCN (2006) red list, and a strategy for its conservation has been proposed by Machado & Lacerda (2016).

Platystigma quadratum   sp. nov.

Figures 13 View FIGURES 8 – 13 , 19 View FIGURES 14 – 19 , 24 View FIGURES 20 – 24 , 32 View FIGURES 29 – 32 , 41 View FIGURES 37 – 41 , 50, 51 View FIGURES 42 – 51 , 60, 61 View FIGURES 54 – 61

Material examined. Holotype ♂: Brazil, Acre State, Senador Guiomard, Reserva Catuaba (10° 03' 60"S, 67° 35' 59"W), IX –2003, Mielke & Casagrande leg. ( ABMM) GoogleMaps   . Two ♂ paratypes with same data as holotype. GoogleMaps  

Etymology. From Latin quadratum-a-um, quadrate, an allusion to the shape of its penis segment 3 in ectal view.

Description of the male holotype. Head. Labium whitish yellow, base of mandible and genae bluish yellow, anteclypeus and postclypeus grayish blue, antefrons brownish. Upper part of head black with metallic green luster. Postocular lobe and occipital crest yellow. Rear of head whitish yellow.

Thorax. Prothorax: pronotum black. Anterior lobe with pair of pale oblong transverse spots. Middle lobe with large pale marking dilated posteriorly ( Fig. 13 View FIGURES 8 – 13 ). Posterior lobe bordered with yellow ( Fig. 13 View FIGURES 8 – 13 ). Propleuron yellow with black markings ( Fig. 13 View FIGURES 8 – 13 ). Pterothorax: mesepisternum ( Fig. 19 View FIGURES 14 – 19 ) black with middorsal carina yellow, antehumeral yellow stripe reduced to triangular marking at about 1/3 of sclerite. Posthumeral yellow stripe not reaching lower part of sclerite. Mesepimeron black. Metapleuron yellow with black stripe along metapleural suture. Venter with anterior triangular and posterior subcylindrical black spots ( Fig. 24 View FIGURES 20 – 24 ).

Wings. Fw hyaline with light brown pseudostigma, with six cells. Hw with large apical area bluish white reaching RP2; pseudostigma blue with eight cells ( Fig. 32 View FIGURES 29 – 32 ). At high saturation, bluish white area becomes whitish blue, surrounded by blue and pseudostigma more intensely blue. Venation: Px in Fw 31, in Hw 33, RP 2 in Fw and in Hw originating at Px 11. IR1 originating at Px 16 in Fw, at Px 14 in Hw. RP2 branching from RP at about half distance from subnodus to tip of wing. Petiolation originates distal to CuP by two times length of CuP in Fw and three times in Hw.

Legs. Femora with proximal 1/3 yellow, distally black on extensor surface and yellow on flexural surface. Tibiae with extensor surface yellow and flexural surface black. Tarsi black.

Abdomen. S1–10 dorsally black, laterally yellow. Cerci black.

Structural characters. Median and lateral portions of posterior prothoracic lobe not separated. Posterior border slightly convex ( Fig. 13 View FIGURES 8 – 13 ). Cleft of anterior lamina shaped as ogival Gothic arch ( Fig. 41 View FIGURES 37 – 41 ). Anterior hamuli with ear-like basal plate. Posterior hamuli with apex curved anteromedially ( Fig. 41 View FIGURES 37 – 41 ). Distal portion of batilliform lamina very small, apex sclerotized ( Fig. 41 View FIGURES 37 – 41 ). Penis segment 3 in ectal view subquadrate with small tongue-like apical lobe and tuft of spines at anterolateral angle ( Fig. 50 View FIGURES 42 – 51 ); in lateral view with medial and distal tuft of spines ( Fig. 51 View FIGURES 42 – 51 ). Penis segment 2 with large tuft of spines near commissure ( Figs. 50–51 View FIGURES 42 – 51 ). Hind border of S 10 in dorsal view with medial concavity ( Fig. 60 View FIGURES 54 – 61 ); in lateral view with distal ½ elevated ( Fig. 61 View FIGURES 54 – 61 ). Cerci in lateral view cylindrical, with distal 1/3 tapering and directed ventrally ( Fig. 61 View FIGURES 54 – 61 ). In dorsal view, distally convergent ( Fig. 60 View FIGURES 54 – 61 ).

Measurements (mm): Hw 47, abdomen 60.

Variations in paratypes. In one of the paratypes the tuft of spines at the anterolateral angle of penis segment 3 is hardly visible.

Female: unknown.

Remarks. P. quadratum   shares with P. humaita   the penis segment 3 subquadrate, with a small tongue-like apical lobe. It differs from it by having a pale apical area only in Hw (in both wings in P. humaita   ).