Mecomera brunnea Audinet-Serville, 1839, 1838

Heleodoro, Raphael Aquino, Alves-Oliveira, João Rafael & Rafael, José Albertino, 2019, Mecomera Audinet-Serville, 1839 (Dermaptera: Spongiphoridae): proposal of new diagnosis, descriptions and illustrations of all three-known species, Zootaxa 4577 (1), pp. 117-130 : 118-124

Mecomera brunnea Audinet-Serville, 1839

Figs. 1 A–E, 2A–C, 3A–D, 4A–D.

Mecomera brunnea Audinet-Serville, 1839: 54 ; Brindle, 1968: 288 (redescription, new illustrations); Steinmann, 1990: 170

(redescription); Sakai, 1991 (comparison of descriptions from different authors). Forficula plana Illiger, in Burmeister, 1838: 752 ; Forficula gracilis Blanchard, in Orbigny,1843: 214 ; Sparatta apicalis Kirby, 1896: 526 ; Sparatta dohrni Kirby, 1903: 68 (new name for Sparatta plana Dohrn, 1865 , a junior secondary homonymy of Sparatta plana

(Illiger, 1839)).

Examined material. BR, AM, km 30 Manaus-Caracaraí, NAF 6 AM, 30.iv.1976, Joselita Maria Santos leg. (3♂ INPA) ; BR, AM, Manaus , Est. [highway] BR-174 , KM 30 , 21.v.1976, Paralupi (1♂, INPA); BRASIL , AM, Manaus , Aleixo, Km 7, 14.vi.1977, Joselita Maria Santos leg. (♂ INPA) ; idem, 20.vi.1978 (♂ INPA); BRASIL , AM, Manaus , Aleixo, Km 11, 15.ix.1978, A. Y. Harada, Col. (2 ♀ INPA) ; BR, AM, Manaus, Reserva Biológica da Campina , BR 174 , 12.iv.2002, Silva AC leg, Manual collecting (♂, ♀ INPA); BRASIL , AM, Reserva Extrativista Unini , 0 3 bocas, 16–28.vii.2004, manual collecting, A. Silva, leg. (♀ INPA); BRASIL , RO [Rondônia], Guaporé , 12°13'19''S– 60°32'44''W, 23.iv.2006, J.A. Rafael & F.F. Xavier, Manual collecting (2 ♀ INPA) BRASIL , AM [Amazonas], São Paulo de Olivença , 03°28'50''S– 68°55'25''W, Campina, 11–14.ix.2005, Malaise trap, J.A. Rafael & F.F. Xavier (2♂ INPA) .

Description of male. Proximal half of body (excluding head appendages) dark brown, becoming mainly light brown to yellow towards apex; body shiny ( Figs. 1A, B ). Measurements (mm) (n=6): body length 9.5–10.0; head width 1–1.2; pronotum length 1.4–1.6; pronotum width 1.0; cercus length 4.2–4.5.

Head cordiform, smooth ( Figs. 1A, C ). Frons and vertex with inconspicuous postfrontal and coronal sutures. Frons with basal margin inconspicuously sinuous ( Figs. 1A, C ). Post-ocular area with postero-lateral margin rounded; vertex concave ( Figs. 1A, C ). Eyes black, diameter slightly less than length of post-ocular area ( Figs. 1A, C ). Antenna with 22 antennomeres, setose from base to apex, dark yellow from scapus to flagellomere 13, yellow from flagellomere 14 to apex ( Figs. 1A, B ); scapus 5.5 times longer than pedicel and 1.5 times longer than flagellomere 1 ( Fig. 1C ). Maxillary and labial palps yellow, setose ( Figs. 1B, C ).

Pronotum hexagonal, 1.6 times longer when measured at widest point, broadening from base to apex, wider at middle, surface roughened, basal and lateral margins convex, apical margin almost straight; midlongitudinal sulcus conspicuous and deep; prozone 5.2 times shorter than metazone ( Figs. 1A, C ). Meso- and metanotum covered by tegmina and posterior wings, respectively. Prosternum dark brown with black spots, sternal plate with oblong basal margin, straight lateral margin and conspicuous emargination on apical margin ( Fig. 1B ). Meso and metasternum light yellow, with several dark brown spots, both striated apically ( Fig. 1B ). Mesosternum with conspicuous sternal plate, with truncated basal margin, broadening towards sinuous lateral margin and slightly emarginated apical margin ( Figs. 1B ). Metasternum with inconspicuous sternal plate.

Tegmina elongated, 2.7 times longer than wide, broadening towards apex; with black longitudinal spots mesally at basal third and transversally at extreme apical; surface roughened, postero-laterally emarginated ( Figs. 1A, D ). Posterior wing almost translucid, covered by small setae. Costal margin straight, with costal area marked by a thin conspicuous line ( Fig 1E ). Squama with two conspicuous light brown spots, at costal and anal margin ( Fig. 1E ). BR + BM broadened at base, gradually narrowing towards apex. MP slender, almost reaching the length of the costal area ( Fig. 1E ) CuA surpassing MP in length, bifurcated at apex ( Fig. 1E ). CuP with three acute edges, with anal margin conspicuously concave; apex widened ( Fig. 1E ). TF small, inconspicuous ( Fig. 1E ). Outer apical area large, approximately half width of the squama ( Fig. 1E ). Broadening of AP-AP1 +2-AP4 reniform, enlarged ( Fig. 1E ).

All legs dorsally light brown from base of basal third to apex of medial third, remaininder light yellow. All femora broadened, with small setae. All tibiae and tarsi densely setose ( Figs. 1A, B ).

Abdomen with lateral margins parallel-sided, dorsally and ventrally covered with small, scattered, smooth setae; all segments apically striated dorsally and ventrally ( Figs. 1A, B ). Tergites 1–3 not narrowed. Tergites 3–4 dark brown, with inconspicuous glandular folds. Tergites 3–9 rectangular; tergites 3–7 1.7 times wider than long, with apical margin almost straight ( Figs. 1A , 2A ); tergite 8 2.5 times wider than long, with apical margin concave; tergite 9 four times wider than long, with apical margin concave ( Figs. 1A , 2A ). Tergite 10 (ultimate) rectangular, 1.5 times wider than long, slightly sinuous laterally and straight apically; apical margin slightly upwardly projected, with dark brown and black spots ( Figs. 1A , 2A ). Pygidium with four conspicuous acute projections, posterior pair pointing backward and anterior pair pointing downward; concavity between posterior projections shallow ( Figs. 1A , 2 A–C). Cercus (forceps) light yellow to brown on proximal half, darker at distal half, slender, slightly shorter than abdomen, mesally with one short acute projection pointing downward; margins finely blackpigmented, apex acute ( Figs. 1A, B ). Abdominal sterna light brown ( Fig. 1B ). Sternites 2–7 rectangular, with lateral margin somewhat straight, apical margin emarginated, slightly concave ( Fig. 1B ). Sternite 8 rectangular, 1.3 times longer than wider, slightly sinuous apically ( Figs. 1B , 2B ). Sternite 9 (penultimate) with lateral margin convex, apical margin slightly concave ( Figs. 1B , 2B ).

Genitalia with functional ejaculatory ductwell sclerotized, elongated, approximately 2.5 times longer than virga; dark brown ( Figs. 3A, C ). Basal vesicle reniform, dorsally widened at proximal half, short and slightly elongated at distal half ( Fig. 3A, B, D ). Virga elongated, reaching base of paramere ( Fig. 3A, B ). Penis lobe broadened, elongated, covered with small scale-like structure ( Figs. 3 B–D); apex of penis lobe bilobed, asymmetrical, left lobule larger than right lobule ( Figs. 3B, D ). Paramere elongated, with basal third bacilliform, slightly widened, gradually narrowing towards apex; apex acute ( Figs. 3 A–D).

Description of female. Similar to male, but having a broader and longer body, except cercus shorter; additionally with the following differences. Legs homogeneously light brown ( Figs. 4A, B ). Abdominal tergite 8 (ultimate) trapezoidal, width gradually narrowing laterally, apically straight ( Figs. 4A, C ). Pygidium trapezoidal, emarginated laterally and posteriorly; apical margin with two dorsal pointed, acute projections ( Fig. 4C, D ). Cercus (forceps) broader and shorter, length 0.6 times that of abdomen ( Figs. 4A, B ). Abdominal sterna light yellow basally and slightly darker distally ( Fig. 4B ). Sternite 7 (penultimate) with, convex lateral margin and strongly convex apical margin ( Figs. 4B, D ). Measurements (mm) (n=6): body length 1010.4; head width 1–1.3; pronotum length 1.2–1.6; pronotum width 1.1; cercus length 2.8–3.0.

Distribution. Bolivia; Brazil: Amazonas and Rondônia [new records]; Colombia; Costa Rica; French Guiana; Nicaragua; Peru. Variations. There are two patterns of variations within the species: 1) having two different dark brown spots

on squama and pygidium bearing four conspicuous projections (as described and illustrated above, Figs. 1E , 2C ); 2) having one single large dark brown spot on squama and pygidium bearing two conspicuous projections and two inconspicuous projections ( Figs. 5 A–D). Furthermore, the following differences on the posterior wing were also noticed in the second pattern ( Fig. 5D ): costal margin with sinuous concavity at approximately half length; costal area marked by MP. Squama with a single large dark brown spot. MP slender, curved at base, almost reaching the squama spot. CuA slender, reaching at maximum half-length of MP, bifurcated at apex. CuP resembling a boot, with costal and anal margin rounded. BR + BM slender at anal half, widening conspicuously towards costal half. TF large, with almost same length of outer apical area. Outer apical area thin, barely reaching a third of the squama width. Broadening of AP-AP1 + 2-AP4 resembling a triangle.

Remarks. Mecomera brunnea differs from M. reichardti by the smooth surface of tergites 4–10 (punctate in M. reichardti ( Figs. 7C , 8 A–C)); in M. brunnea basal vesicle reniform, widened at proximal half, short and slightly elongated at distal half; basal third of paramere bacilliform and slightly widened (in M. reichardti basal vesicle conspicuously slender at proximal half, rounded at distal half; the paramere with basal margin conspicuously rounded, antero-lateral margin concave, postero-lateral margin convex, surface of the penis lobe smooth ( Figs. 7 D–E)).

Mecomera brunnea differs from M. chacoensis in having one mesal projection on each cercus (two or three mesal projections on each cercus in M. chacoensis ). It is known that Dermaptera species can have intraspecific morphological variation on the cerci, as with M. chacoensis ( Brindle 1968; Steinmann 1990). However, it is also true that some New World Dermaptera do not have significant variation on the cercus and therefore it can be reliably used for differentiation, as verified for Mecomera ( Brindle 1968) . Due to the relatively high number of specimens analyzed, it is safe to separate males of M. brunnea from those of M. chacoensis by the number of projections on the cercus.

Figures

FIGURE 1. Mecomera brunnea ♂. A) Habitus in dorsal view; B) Habitus, ventral view; C) Head and pronotum in dorsal view; D) Tegmina in dorsal view; E) Schematic drawing of the base of the posterior wing. Abbreviations: AP = anal posterior, BM = medial basiveinal, BR = radial basiveinal, CuA = cubitus anterior, CuP = cubitus posterior, MP = media posterior, S = sternite, T = tergite, TF = transverse fold area.

FIGURE 2. Abdominal sclerites of Mecomera brunnea ♂. A) Tergites 8‒10 and pygidium, dorsal view; B) Sternites 8‒9 and pygidium, ventral view; C) Pygidium, ventral view.

FIGURE 3. Male genitalia of Mecomera brunnea ♂ A) Complete genitalia in dorsal view; B) Partial genitalia, excluding ejaculatory duct in dorsal view; C) Complete genitalia in ventral view; D) Partial genitalia, excluding ejaculatory duct in ventral view.

FIGURE 4. Mecomera brunnea ♀ from Rondônia, Guaporé. A) Habitus in dorsal view; B) Habitus in ventral view; C) Apex of abdomen, dorsal view; D) Apex of abdomen, ventral view.

FIGURE 5. Posterior wing, male terminalia and partial genitalia, excluding ejaculatory duct of Mecomera brunnea ♂. A) Schematic drawing of the base of the posterior wing B) Tergites 8–10 and pygidium, dorsal view; C) Sternites 8–9 and pygidium, ventral view; D) Pygidium, ventral view. Abbreviations: AP = anal posterior, BM = medial basiveinal, BR = radial basiveinal, CuA = cubitus anterior, CuP = cubitus posterior, MP = media posterior, TF = transverse fold area.

FIGURE 7. Mecomera reichardti, holotype ♂. A) Habitus in dorsal view; B) Head and pronotum in dorsal view; C) Tergites 5–10 and cercus, dorsal view; D) Genitalia, ventral view; E) Partial gentalia, excluding ejaculatory duct, ventral view. Photos by MZUSP staff.

FIGURE 8. Mecomera reichardti. A) Paratype ♂, tergites 7‒10, pygidium and cercus, dorsal view; B) Paratype ♀, habitus in dorsal view; C) Paratype ♂, habitus in dorsal view; D) Tergites 6‒8, pygidium and cercus, dorsal view. Photos by MZUSP staff.