Decimiana gaucha, Maldaner, Caroline & Rafael, José Albertino, 2017

Maldaner, Caroline & Rafael, José Albertino, 2017, A new species of Decimiana Uvarov from Brazil, with updated key to species and remarks on their geographic distribution (Mantodea: Acanthopidae, Acanthopinae), Zootaxa 4291 (3), pp. 521-530: 522-526

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Decimiana gaucha

sp. nov.

Decimiana gaucha   sp. nov.

( Figures 1 View FIGURE 1 , 4 View FIGURE 4 )

Type material: holotype ♂ (deposited at INPA), BRAZIL, RS [Rio Grande do Sul], Capão do Leão [31°46'3''S, 52°26'55''W], 28.xi.1994 (A. R. Reis Jr. Leg) GoogleMaps   . Holotype is in good condition. Other material (all paratypes): Brasil, Rio Grande do Sul, Capão do Leão [31°46'3''S, 52°26'55''W], 1 ♂, 02.xi.1994 (A. Pinho Leg) ( INPA) GoogleMaps   , 1♂, idem, x.1995 (U.F. Thies leg.) (INPA), 1 ♂, idem, v.1996 (F.C. Maia leg.) (INPA); 1 ♂, idem, x.1996 (D. M. Coleleg.) (MECB); 1 ♂, RS, Pelotas [31°46'19"S, 52°20'33"W], xi. 1995 (N. Meyer leg.) ( MECB) GoogleMaps   ; 1 ♂, idem, xii.1996 (L. Krüger leg.) (MECB); 1♂, idem, xi. 1996 (C.V. Silveira leg.) (MECB), 1 ♂, Piratini [31°26'53''S, 53°06'15''W], x.1995 (A. R. Romano leg.) ( MECB) GoogleMaps   .

Diagnosis: Body brown ( Fig. 1A View FIGURE 1 ). Ventral phallomere (Vph) ( Fig. 1D View FIGURE 1 ) with distal process curved, gradually tapering distally; proximal process of Vph subtriangular, robust, with ribs on surface. Right dorsal phallomere (Rdp) ( Fig. 1F View FIGURE 1 ) with ventral process falciform, pointed and with teeth (spines) well marked on the base; ventral plate with denticles. Left dorsal phallomere (Ldp) ( Fig. 1E View FIGURE 1 ) with anterior process globose, with marginal denticles irregular and not pointed spines (teeth), distal portion with denticles, ending in a subtriangular point; membranous lobe small, slightly pronounced, with granulations and few thin setae.

Description (male holotype)

Body coloration: predominantly brown ( Fig. 1A View FIGURE 1 ).

Head ( Fig. 1B –C View FIGURE 1 ). triangular in frontal view, its dorsal surface with sparse granulations; cuticle is brown (darker on top), with various contrasting maculae, thus appearing mottled; vertex more elevated than compound eyes, the latter conical in shape, and with a spine-like, apical process; ocellar tubercle developed, bearing two small and triangular, posterior projections (these are darker than the rest of ocelli) ( Fig. 1C View FIGURE 1 ); lateral ocellus slightly conical, the central one is transversely oval; scutellum hexagonal ( Fig. 1B –C View FIGURE 1 ), lighter than remaining of head, upper angle bifurcated, branches rounded and with small granulations; antenna predominantly moniliform, scape longer than any other individual antennomere.

Thorax ( Fig. 1A View FIGURE 1 ). Pronotum: longer than wide, with longitudinal median line well marked, proximal portion darker, bearing small granulations; supracoxal swelling well marked; prozona shorter and more elevated than metazona in lateral view, proximal portion with rounded edge; metazona shorter than prothoracic coxae. Legs: prothoracic leg with rectangular coxae, like a bar, light brown with darker maculae, surface exhibiting granules (most on anterior portion), dorsal margin with denticles; femur robust, marbled brown, with granules on both it posterior and anterior aspects (granules more evident on the latter), F=4DS/14AvS/6PvS; with denticles in between PvS; tibiae marbled, dorsal edge slightly convex, with small granules on its posterior aspect; T=15AvS/19PvS, respectively, tibial spines ventrally serrated and reclined; tarsomere I longer than all other tarsomeres taken together; tarsomeres spotted. Meso- and metathoracic legs with triangular coxae, robust, and slightly pilose; meso- and metafemora long and pilose, subrectangular in shape, marbled brown, ventral groove well-marked, and bearing one distal spine; meso- and metatibiae long, subretangular, marbled brown, pilose, and bearing two distal spines; all tarsomeres of cursorial legs pilose. Wings: mesothoracic wing ( Fig. 1A View FIGURE 1 ) projecting beyond abdomen in resting position; costal area narrow, wider proximally, brown, darker than discoidal and anal areas; costal vein is slightly sinuous; stigma discrete, of color similar to the rest of the wing, just slightly brighter; jugal area dark brown ( Fig. View FIGURE 1

1A). Metathoracic wings ( Fig. 1A View FIGURE 1 ) approximately as long as the mesothoracic pair, anal edge with marked sinuosity; costal area narrow, colored as in the mesothoracic wing; cells of discoidal area with dark brown central macula, the same become lighter or absent along the more marginal, distal cells.

Abdomen. Long, rhomboidal in shape; tergites light brown with black, shiny macula distally, and with wider maculae on tergites V and VI; tergite V, dark, with rounded apex and a lateral swelling.

Male Genitalia ( Fig. 1D –F View FIGURE 1 ): Vph ( Fig. 1D View FIGURE 1 ) subretangular, distal process (Dip) curved ( Fig. 1D View FIGURE 1 ), gradually tapering distally, with apex somewhat rounded; proximal process (Pp) ( Fig. 1D View FIGURE 1 ) subtriangular, robust and with striae, more sclerotized than the rest of the phallomere, apex of the process triangular. Rdp ( Fig. 1F View FIGURE 1 ) subtriangular, anterior apodeme (Ap) slightly sclerotized and curved; membranous part with rounded apex and long setae; ventral process (Vpr) more sclerotized than anterior apodeme (Ap), falciform, pointed, with well-marked spines proximally, ventral plate (Vpl) esclerotized as in ventral process (Vpr), with denticles. Ldp ( Fig. 1E View FIGURE 1 ) longer than wide, posterior process (Pop) slightly sclerotized, with small setae; anterior process (Anp) globose, with irregular denticles and without pointed spines (teeth), distal portion with denticles, ending in a subtriangular point; membranous lobe (ml) slightly pronounced, small, with granulations and few thin setae ( Fig. 1E View FIGURE 1 ).

Measurements (holotype; in mm): body length: 53; head width: 6; pronotum length: 10; prozona: 3.8; prothoracic coxa: 9; prothoracic femur: 10; prothoracic tibia: 6; tibial claw: 2.4; mesothoracic wing: 41; metathoracic wing: 40. Dissected genitalia contained in a microvial with glycerin and pinned along the specimen.

Etymology: the epithet gaucha   means "being from Rio Grande do Sul ", the most southern state from Brazil and the geographic origin of the type series.

Geographical records: Brazil (RS) ( Fig. 4 View FIGURE 4 ).

Variation observed in paratypes. Body coloration among specimens occurs in various dark shades of brown. Some specimens exhibit some variation in density and arrangement of the granulations and/or denticles on the proximal process of the Vph, as well as on the ventral process of the Rdp. Some specimens exhibit ventral plate of the Ldp with membranous lobe bearing some setae, however these are always very thin and in few numbers. Ldp with some variation in the quantity and arrangement of the granulations and/or denticles on the anterior process of the ventral lamina. Measurement ranges: body lenght, 47–53; head width, 5.5–6; pronotum lenght, 9–10; prozona, 3–3.8; prothoracic coxa, 7.5–9; prothoracic femur, 9–10; prothoracic tíbia, 5–6; tibial claw, 2–2.2; mesothoracic wing, 37–41.

Comparative notes. The new species differs from other members of Decimiana   in having the distal process of Vph broad and gradually tapering distally ( Fig. 1D View FIGURE 1 ), whereas the same in the other species is narrower and suddenly tapers distally ( Fig. 3 View FIGURE 3 ). The anterior process of Vph of D. gaucha   is subtriangular in shape, similar to that of D. elliptica   , but in the former the process is much more robust and has grooved surface ( Fig. 1D View FIGURE 1 ), while in D. bolivari   , D. clavata   . D. hebardi   , D. rehni   and D. tessellata   , the same structure is narrower, not grooved, and may exhibit some granulations or denticles. In addition, the ventral process of the Rdp of D. gaucha   is strongly curved, falciform, sharp and bears denticles ( Fig. 1F View FIGURE 1 ), while in the other species the same is less strongly curved and pointed, denticles are sparse when present, or it may exhibit ribs only. The anterior process of the ventral lamina of the Ldp of D. gaucha   bears irregular teeth-like, blunt spines, the same are sparser towards the pointy apex ( Fig. 1E View FIGURE 1 ) thus resembling the condition observed of D. tessellata   , but in the latter species the anterior process of the ventral lamina is more developed, with well-marked spines and the apex not markedly pointed ( Fig. 2 View FIGURE 2 F). Decimiana bolivari   , D. hebardi   and D. rehni   differ from D. gaucha   for having the anterior process of the ventral lamina robust, varying the quantity of granulations or setae present along the structure ( Fig. 2 View FIGURE 2 ), and the distal portion has small granulations (denticles) and is not pointed. The anterior process of the ventral lamina of D. elliptica   and D. clavata   is not particularly developed, but the distal portion of the same is characteristic for being short and robust, its surface heavily sclerotized and bearing denticles ( Fig. 2 View FIGURE 2 ). The membranous lobes of the Ldp is normally little pronounced in D. gaucha   sp. nov. ( Fig. 1E View FIGURE 1 ), with few to no granulations or setae, whereas in D. bolivari   , D. clavata   , D. elíptica   , D. hebardi   , D. rehni   and D. tessellata   the same lobe generally exhibit a conspicuous number of setae and/or granulations (Fig, 2).

We were able to identify two projections, both small and triangular, in the superior/posterior portion of the ocellar triangle ( Fig. 1C View FIGURE 1 , highlighted in green), which until now have never been described for the genus. These projections are present in D. gaucha   sp. nov., D. tessellata   and D. bolivari   , but its presence in the other species could not be verified at this time.


Instituto Nacional de Pesquisas da Amazonia


Universidade Federal de Pelotas, Museu Entomologico Ceslau Biezanko