Dystacta tigrifrutex Tedrow & Svenson

Tedrow, Riley, Nathan, Kabanguka, Richard, Nasasira & Svenson, Gavin J, 2014, A new species of Dystacta Saussure, 1871 from Nyungwe National Park, Rwanda (Insecta, Mantodea, Dystactinae), ZooKeys 410, pp. 1-21 : 8-15

Dystacta tigrifrutex Tedrow & Svenson sp. n.

Repository.

Holotype Male (CLEV GSMC004381). Allotype Female (CLEV GSMC004420). The Cleveland Museum of Natural History, Cleveland, OH, USA

Holotype and Allotype labels: Pinned. Rwanda, Nyungwe National Park, -2.478121, 29.200055, 2446 m, 4-9 May 2013, Coll: R. Tedrow & G.J. Svenson.

Natural history.

Based on the collecting location on the ground for both the male and the female and the fact that the female is apterous, we presume that the species utilizes a low vegetation or forest floor habitat. This would be consistent with morphologically similar species in Africa ( Chroicopterinae ), Asia (some Amelinae ) and South America (some Thespinae ). The female walks nimbly through vegetation and uses her forelegs periodically, pausing and moving them similar to boxing mantises (species of Hestiasula ). The male took flight readily and was difficult to observe and expired quickly in captivity.

Diagnosis.

Male brown with elongate wings. The easiest way to distinguish Dystacta tigrifrutex from Dystacta alticeps is the distinct black and whitish pattern on the prosternum of Dystacta alticeps (Fig. 2A) while Dystacta tigrifrutex has a speckled pattern on the prosternum (Fig. 2B). In addition, the presence of tight ciliation on the discoidal region of the forewings of male Dystacta tigrifrutex compared with the smooth surface seen in Dystacta alticeps . Females are apterous in Dystacta tigrifrutex and brachypterous in Dystacta alticeps .

Description.

Male.Holotype (Figs 1A, 3 A–B). Body length 34.72; forewing length 28.2; hindwing length 27.16; pronotum length 4.65; prozone length 1.77; pronotum width 2.11; pronotum narrow width 1.03; head width 3.46; head vertex to clypeus 1.53; frons width 1.27; frons height 0.595; prothD. tigrifrutex D. tigrifrutex oracic femur length 5.19; mesothoracic femur length 5.46; mesothoracic tibia length 4.59; mesothoracic tarsus length 3.85; metathoracic femur length 6.48; metathoracic tibia length 7.26; metathoracic tarsus length 5.30; anteroventral femoral spine count R12/L12; posteroventral femoral spine count R4/L4; anteroventral tibial spine count R11/L10; posteroventral tibial spine count R7/L8.

A DK cyclopean ear present on the ventral surface of the metathorax (see Yager and Svenson 2008 for description of the DK form).

Head (Fig. 4A): Transverse, eyes slightly exophthalmic; the vertex rounded, the parietal sutures present; juxta-ocular protuberances absent. Frontal suture faint with a medial carina forming a continuous arc. Ocelli large, protruding on small cuticular mounds, but the region between all three slightly raised, with a triangular shape; the lateral ocelli oriented outward; the region around the raised ocelli and below the frontal suture depressed. Clypeus transverse, the upper margin convex, the lateral margins tapering; surface with moderate sculpting; the lower margin of the clypeus slightly concave. Labrum rounded. Antennae with a mostly pale pedicel and scape, but both with small black marks; the flagellomeres mostly pale in the basal half, transitioning to black on the distal end of the antennae, the setae dark colored, with 4-5 setae on each flagellomere. Anterior surface of head mostly pale or ochre with tiny dark speckling across the surface; frons ochre with dark splotches of black, a transverse black band just below the antennae extends laterally across the anterior surface of the eyes; the clypeus ochre with dark splotches of black; labrum ochre with black splotches, with ochre mandibles; vertex ochre with black splotches; raised area around ocelli black. Maxillary palpi ochre with black spots with the terminal segment black on one side.

Pronotum (Figs 2B, 5A): Longer than wide, with an expanded supra-coxal bulge; dorsal surface smooth. Prozone with two angled carina oriented anterolateral from the supra-coxal sulcus; medial region of prozone peaked, sloping steeply to the anterior margins; medium length with margins gradually tapering anteriorly to a rounded anterior margin; the margins smooth, but with setae present. Metazone with two small depressions posterior to the supra-coxal sulcus; two large and prominent tubercles positioned on each side of the medial line just anterior to the posterior margin, a raised carina oriented anterolaterally, extending to the lateral margins of the metazone. Metazone with concave lateral margins tapering posteriorly until two thirds from the supra-coxal bulge, then widening to the posterior margin; margins smooth, but with setae present; the dorsal surface of the metazone not depressed. Ochre with faint black spots and more opaque black lines laterally. Prosternum ochre with dark brown speckling that becomes more dense posteriorly.

Forelegs: Femur shape normal with a straight dorsal margin; spines robust, pale proximally and black distally; femoral groove to accommodate the tibial spur in the proximal half; the posterior surface smooth; 4 discoidal spines. Posterior surface of femur ochre with black stippling; anterior surface ochre with black speckling that is more concentrated along the outer margins; ventral surface with a black band between the second most proximal and third most proximal posteroventral spines as well as a black band extending half way from the most distal posteroventral spine to the genicular spine; setae dispersed across a pale ventral surface. The discoidal spines robust, the third from the base very large and robust, twice the length of the second and fourth. Anteroventral femoral spines 1, 3, 5, 7, 9-11 short, but of similar length to each other; anteroventral femoral spines 2, 4, 6, 8 long, but of similar length to each other; posteroventral femoral spines all of the same length; the posterior and anterior genicular spines small, but robust. Tibia with numerous setae along the dorsal margin and on the posterior, anterior and ventral surfaces; anterior and posterior surfaces ochre with black stippling; posterior external surface ochre with groups of dense black stippling, occasionally with a black stippled line beginning at the base of the tibio-femoral joint to about a quarter of the way to the distal end to the tibia. Posteroventral tibial spines 1-6 of similar length, the distal spine 7 larger than the others; anteroventral tibial spines gradually increase in length from the most proximal to the most distal spine. Forecoxae mostly smooth with setae interspersed throughout, a few tubercles present along the margins, but none are robust as seen in females.

Meso- and Metathoracic Legs: Femora with pronounced ventral (posterior) carina; dorsal (anterior) carina faint. The femora, tibiae and tarsi with dense setae. Femora mostly pale with a number of black bands near the distal terminus on the posterior surface, the most pronounced running just dorsal to the ventral carina; anterior surface with a number of black bands along the ventral carina. Tibia pale with a number of faint black marks, some appearing as bands. Tarsi short; the first three tarsal segments are light proximally and have a dark spot on the distal end, the remaining segments black; mesotarsi and metatarsi with the first segment shorter than the remaining segments combined.

Wings: Elongate, extending well beyond the terminus of the abdomen. Forewing slender, the costal region narrow and opaque brown; dense setae along the anterior margin; the entire surface tightly ciliated; the discoidal region smoky grey with few dark splotches, three or four in the distal half; the veins more pigmented than surrounding cell colors, but small black sections disperse across all veins and occasionally along the major wing veins, increasing in frequency moving toward the distal terminus. Hindwings with setae along anterior margin, the surface tightly ciliated; matching coloration of forewing, but the costal region translucent grey in the proximal half, fading to opaque brown in the distal half; black marks along the distal terminus of the discoidal region; the terminus of the discoidal region projecting well beyond the margin of the anal region, the wing appearing highly elongate.

Abdomen: Smooth, tubular with brown and black coloration. A black medial line on the ventral surface that is contiguous across sternites; the posterior half of sternites fading from brown to black; the surface with numerous setae. Tergites rounded at the postero-lateral margins. Supra-anal plate and cerci not known since the posterior half was detached and carried away by opportunistic ants when drying.

Genital Complex: Due to specimen damage, the genitalia are absent.

Female.Allotype (Figs 1B, 3 C–D). Female was preserved in ethanol and later pinned, causing some deformation in the abdomen. Body length 19.82; pronotum length 5.89; prozone length 2.56; pronotum width 3.83; pronotum narrow width 1.83; head width 4.83; head vertex to clypeus 3.72; frons width 1.87; frons height 1.10; prothoracic femur length 6.61; mesothoracic femur length 5.46; mesothoracic tibia length 4.82; mesothoracic tarsus length 3.91; metathoracic femur length 6.18; metathoracic tibia length 7.10; metathoracic tarsus length 4.73; anteroventral femoral spine count R12/L11; posteroventral femoral spine count R4/L4; anteroventral tibial spine count R11/L11; posteroventral tibial spine count R9/L9.

A DO cyclopean ear present on the ventral surface of the metathorax (see Yager and Svenson 2008 for description of the DO form).

Head (Fig. 4B): Slightly transverse, eyes not particularly exophthalmic; vertex highly convex, the parietal sutures present; juxta-ocular protuberances absent. Frontal suture faint, but a forming dorsally oriented curved. Ocelli absent or vestigial, but lenses not visible; a carina connecting former ocellar locations connecting all three and forming a U; region within the U and below the frontal suture depressed. Frons transverse with an angled carina below the antennae, meeting medially with a raised point. Clypeus transverse, the upper margin convex, the lateral margins tapering to a rounded distal terminus; surface with a medial, transverse carina. Labrum rounded with a darkened distal terminus. Antennae with a mostly pale pedicle that has a black band distally; scape black, flagellomeres pale basally and fading to black within 10 antennomeres; setae sparse basally, becoming more dense distally. Anterior surface of head mostly pale or ochre with tiny dark speckling across the surface; frons with a transverse black band just below the antennae; labial palpi ochre, maxillary palpi ochre then with a black spot on both sides of the terminal segment.

Pronotum (Fig. 5B): Longer than wide, with an expanded supra-coxal bulge; dorsal surface with uneven tiny depressions and scattered black tubercles. Prozone with two angled carina oriented anterolateral from the supra-coxal sulcus; medial region of prozone peaked, sloping steeply to the lateral margins. Metazone with uneven sculpting across the surface, two depressions posterior to the supra-coxal sulcus; two large and prominent tubercles positioned on each side of the medial line just anterior to the posterior margin. Margins of the prozone convex, tapering sharply to a narrowed, rounded anterior margin; margins of metazone strongly convex, tapering to a narrow constriction medially before widening to the posterior margin. Small, blunt tubercles present on the margins of the prozone; a few large tubercles present on the margins of the metazone, diagonally pointed setae protruding from the posterior side of the lateral half of the tubercle. The supra-coxal sulcus strongly defined and sweeping anteriorly prior to the expanded lateral margins at the supra-coxal bulge. Metazone provides the lateral expansion at the supra-coxal bulge; the dorsal surface flat, but bulging over the lateral margins in the anterior half. Prosternum ochre with dark brown speckling that becomes more dense posteriorly.

Forelegs: The femur squat, almost forming a triangle; spines robust, pale basally and black distally; femoral groove to accommodate the tibial spur just proximal to the middle. The posterior surface of the femur with a marginal carina; dorsal margin narrowing, almost lamellar along the slightly convex margin; dorsal margin with small tubercles that give rise to small hairs; the posterior surface with numerous small tubercles; 4 discoidal spines. The ventral surface of the femur pale with numerous tubercles medially distal to the discoidal spines, each giving rise to a long hair, tubercles continue just proximal to the discoidal spines until the junction with the trochanter; the discoidal spines robust, the third from the base very large and robust. The anterior surface of the femur mostly pale, but with black markings along the ventral margin anterior and posterior to the femoral groove, the groove itself pale; black speckling across the surface. Anteroventral femoral spines (proximal to distal) 2, 4, 6, 8, 12 long, but of similar length to each other, spines 1, 3, 5, 7, 9-11 short, but of similar length to each other; posteroventral femoral spines all of similar length; the posterior and anterior genicular spines small, but robust. Tibia robust with rare, fine setae on the surface and near the lateral margins of the ventral surface; posterior surface ochre with black stippling, ventral surface ochre and lustrous; posteroventral and anteroventral tibial spines gradually becoming longer from the proximal to the distal end. Coxae with tubercles and setae across the surface, the dorsal margin with setae and a few strong tubercles; the anterior surface mostly ochre with small black spots, a large black marking near the distal margin, the distal lobes ochre.

Meso- and Metathoracic Legs: Femora with ventral (posterior) carina well developed; dorsal (anterior) carina absent; surface with numerous small, fine setae; darkly speckled with black markings, sparse proximally, becoming more dense distally, but with a pale band in the distal half. Coxae with numerous black markings speckling the surface. Tibia round, covered with setae; mostly black with two pale bands, one in the proximal half and the other in the distal half. Tarsi short with ample setae; mostly black with the first three tarsal segments are light proximally and darken toward the distal end, the remaining segments black; mesotarsi and metatarsi with the first segment shorter than the remaining segments combined.

Wings: Apterous with no visible vestiges.

Abdomen (Fig. 6 A–B): Very broad, elliptical, the widest being the middle. Tergites and sternites with small, black tubercles along the posterior margins; fine setae disperse across dorsal and ventral surface; each tergite with a medial keel, more pronounced anteriorly. Described from the ethanol preserved specimen, plates 2,3,4, and 5 with small carinae near the lateral margin forming a 45 degree angle with the distal margins of their respective segments, the carinae highest at the margin and descending medially at approximately a 45 degree angle. Tergites rounded at the postero-lateral margins. Supra-anal plate transverse, evenly rounded terminus. The ovipositor enlarged and broad, projecting far beyond the distal margin of the supra-anal plate and the cerci. Cerci round, tapering to a point.

Nymphs.First Instar. Length 3.89; pronotum length 1.21; prozone length 0.52; pronotum width 0.73; pronotum narrow width 0.43; head width 1.39; prothoracic femur length 1.61; mesothoracic femur length 1.38; mesothoracic tibia length 1.28; mesothoracic tarsus length 1.23; metathoracic femur length 1.89; metathoracic tibia length 1.79; metathoracic tarsus length 1.29; anteroventral femoral spine count R12/L12; posteroventral femoral spine count R4/L4; anteroventral tibial spine count R10/L10; posteroventral tibial spine count R8/L8.

Head: Transverse, eyes exophthalmic; vertex highly convex, parietal sutures present; juxta-ocular protuberances absent. Frontal suture forming a dorsally oriented curve. Ocelli not fully developed; the anterior ocellus raised; the location of the lateral ocelli marked by yellow bumps, connected by a U-shaped carina; the region within the U and below the frontal suture slightly depressed. Frons transverse with an angled carina below the antennae, meeting medially with a slightly raised point. Clypeus transverse, the upper margin convex, the lateral margins tapering; surface with a medial, transverse carina. Labrum rounded with a darkened distal terminus. Antennae with a faded black pedicel; scape pale with black splotching; flagellomeres pale basally and fading to black within four antennomeres; setae very sparse basally, becoming slightly more dense distally. Anterior surface of head dark brown with light brown spots; a pale ring formed around the circumference of the antennal insertion sites and a pale arc formed between the eyes posterior to the ocelli. Labial and maxillary palpi segments black basally with a distal light brown terminus.

Pronotum: Longer than wide, with an expanded supra-coxal bulge; dorsal surface smooth. Prozone with a strongly peaked medial region, sloping steeply to the lateral margins. Metazone smooth with a continuation of the peaked region of the prozone sloping steeply to the lateral margins; two small bumps are found on either side of the midline at the distal end of the metazone.

Forelegs: The femur squat, nearly triangular; spines robust with a blackish-brown coloration; femoral groove to accommodate the tibial spur proximal to the middle. The posterior surface of the femur with a marginal carina; dorsal margin narrowing, almost lamellar along the slightly convex margin; dorsal margin with small tubercles that give rise to small hairs. The ventral surface blackish-brown with occasional tubercles giving rise to small hairs; the discoidal spines robust, the third from the base very large and robust. Anterior surface of femora blackish-brown; the groove blackish-brown as well. Anteroventral femoral spines (proximal to distal) 2, 4, 6, 8, 12 are long and of similar length to each other while spines 1, 3, 5, 7, 9-11 are short and of similar length to each other; posteroventral femoral spines all of similar length; the posterior and anterior genicular spines small, but robust. Tibia robust with several setae on the anterior surface and near the lateral margins of the ventral surface; posterior surface ochre; posteroventral and anteroventral tibial spines gradually becoming longer from the proximal to the distal end. Coxae smooth; the surface ochre with blackish-brown spots and a blackish-brown band at the distal end; the distal lobes ochre.

Meso- and Metathoracic Legs: Femora with ventral (posterior) carina; dorsal (anterior) carina absent; surface with numerous small, fine setae; ochre with faint, small brown spots and three wide, faint brown bands. Coxae ochre. Tibia round, covered with setae of varying size; dark brown with four sand colored bands. Tarsi short and covered with setae; black and blackish-brown in color; mesotarsi and metatarsi with the first segment shorter than the remaining segments combined.

Abdomen: Broad, elliptical, widest in the middle. Tergites with a medial keel, more pronounced anteriorly. Setae occurring on the lateral margins projecting laterally. Tergites rounded at the postero-lateral margins. Supra-anal plate transverse. Cerci round and short, tapering to a point.

Ootheca

(Fig. 6 C–D). Measurements. Length 11.12; width 6.40; height 5.24; perimeter (dorsal perspective) 33.87; perimeter (from lateral perspective) 43.23. From the dorsal perspective, the ootheca appears elliptical, with a distinct dorsal point on the posterior end where the egg-case laying terminated. The ootheca is convex ventrally and concave dorsally from the lateral perspective. The anterior end is larger than the remainder of the ootheca, which is consistent in girth with the exception of the terminal dorsal point. Large egg chambers can be seen in rows perpendicular to the top and bottom of the egg-case. The emergence area takes up the majority of the dorsal surface. There is very little air space, the egg chambers extending nearly to the perimeter of the oothecae. The interior of the ootheca is a dark to light reddish brown with a foam textured light brown cast covering the external surface. The method of attachment for this species appears to be smooth vertical surfaces, with no apparent ventral circlet at the point of attachment. This hypothesis is based off the observation of a single specimen that laid its ootheca on the side wall of a mesh cube container in which it was temporarily held (the flexible surface may have influenced the convexity of the ventral surface). The cube contained several twigs at various angles as well as leaves.

Etymology.

The word tigrifrutex is derived from the latin word tigris (meaning tiger) and the latin word frutex (meaning bush). This name was crafted to reflect the behavior of the female, whose morphology suggests that she is adapted for hunting prey close to the ground and in the undergrowth.