Endecous (Pedroecous) troglobius, Castro-Souza & Zefa & Ferreira, 2020

Castro-Souza, Rodrigo Antônio, Zefa, Edison & Ferreira, Rodrigo Lopes, 2020, New troglobitic and troglophilic syntopic species of Endecous (Orthoptera, Grylloidea, Phalangopsidae) from a Brazilian cave: a case of sympatric speciation?, Zootaxa 4810 (2), pp. 271-304 : 285-293

Endecous (Pedroecous) troglobius n. sp.

( Figures 36, 41–43, 44–46, 47–55, 56–59, 60–65, 66–73, 74 , 78–80, 84–86 , 88 , 97, 99, 100–101 , 107 , Tables 2, 4 –6).

Material Examined: Holotype, ♂, ISLA 77744, Brazil, Minas Gerais State, municipality of Luislândia, found in the deepest regions of the Lapa Sem Fim cave (16° 08’ 55”W, 44° 37’ 40”S), 06.ix.2017, R. L. Ferreira, leg. Holotype condition: head, left legs I, II, III, and right tegmen were detached, and maintained in holotype’s tube . Paratypes, 2 ♂♂, 17.iv.2014, ( ISLA 12337; 12339), R. L. Ferreira, leg. ; 1 ♂, 18.iv.2017, ( ISLA 43342), R. L. Ferreira, leg. ; 2 ♂♂, 06.ix.2017, ( ISLA 77745; 77746), R. L. Ferreira, leg. ; 1 ♀, 17.iv.2014, ( ISLA 77747), R. L. Ferreira, leg. ; 2 ♀♀, 18.iv.2017, ( ISLA 43343; 46634), R. L. Ferreira, leg. , all specimens collected in the same locality of holotype .

Distribution: Deeper portions of the Lapa Sem Fim cave ( Fig. 107 ), municipality of Luislândia, Minas Gerais State, Brazil ( Fig. 1A, B ).

Etimology: Specific epithet “ troglobius ”, from ancient greek τρώγλη (trṓglç, “hole”) + βίος (bíos, “life”) + –ite, refers to the term ‘troglobite’, designated for obligate subterranean species.

Diagnosis. Combination of the following characteristics: phallic complex short, and wide in general view in comparison to E. (P.) didymus n. sp. ( Figs 78–80, 84–86 ); pseudepiphallic membranous shield short ( Fig. 42 , Ps.ms); pseudepiphallic dorsal branch long, hook-shaped, rounded at apex, and with projections more curved inward and closer to each other in comparison to E. (P.) didymus n. sp. ( Figs 41, 45–46 , Ps.db); pseudepiphallic arm field developed in comparison to E. (P.) didymus n. sp. ( Figs 84–86 , blue slice); ectophallic arc well developed, U-shaped in ventral and previously inclined in dorsal view ( Fig. 43 , Ect.Arc); endophallus developed ( Figs 44–46 , End.Sc.a, yellow arrow indicates the apodeme); compound eyes with unpigmented ommatidia ( Figs 48–49 , 88 ); body is lighter than E. (P.) didymus n. sp. ( Fig. 97 ); courtship song dominant frequence (DF) with an interval covering larger values compared to E. (P.) didymus n. sp., 3.8–4.0 kHz (max-min), n = 4 ( Tab. 3).

Description, male holotype. Body color. The specimen designated as a holotype was reared in the laboratory, thus receiving light during observation periods, what caused an increase in tegumentar pigmentation when compared to individuals from natural populations inhabiting an aphotic zones: dorsal head, pronotum and right tegmen yellowish-orange pale ( Figs 47–52 ), white ventrally, abdomen yellow pale ( Figs 52–53 ), entire legs brownish, except femora base whitish which is more advanced and pale in comparison to E. (P.) didymus n. sp. ( Figs 56–59 ), cerci uniformly yellow pale. Head ( Figs 47–49 ), thorax ( Figs 50, 52, 56–59 ) and abdomen ( Figs 52–55 ) with morphological description similar to E. (P.) didymus n. sp. as shown in the figures ( Figs 8–9, 10, 12 , 16–19 , 13–15 ). Differing only in the following characteristics: head less elongated in frontal view (3.7 mm length and 2.9 mm width); gena, clypeus, frons, labrum, mandibles, maxilar and labial palpomeres more whitish in conparasion to E. (P.) didymus n. sp.; compound eyes with unpigmented ommatidia ( Figs 47–49 ). Thorax. Pronotum more pubescent compared to E. (P.) didymus n. sp. ( Figs 50 and 52 ). Right tegmen ( Figs 51, 60 ), mirror oval with two crossveins and three cells; harp with three well marked crossveins, and four cells, the first proximal cell has two small reticular veins in diagonal; lateral field marked by 11 reticular accessory veins bifurcated and connected by retucular veins to each other; basal field with veins 1A, 2A and 3A well-marked, with two secondary veins connected to CU 2, the second is less distinct; 3A veins bifurcated ( Figs 51 and 60 ); stridulatory file with 64 teeth. Abdomen: cerci shorter (12.1 mm ± 1.9 mm); supranal and subgenital plate unpigmented ( Figs 53–55 ).

Observations in Paratypes

Male phallic sclerites (paratype, ISLA 43342, Figs 41–46 , 79, 85 ). The morphological description of this structure is similar to E. (P.) didymus n. sp., however, has the following differences: phallic complex slightly wider ( Figs 41, 46 ). Pseudepiphallus: arm more curved inward ( Fig. 41 , Ps.Arm); pseudepiphallic dorsal projections more curved inward and closer to each other ( Figs 41, 45–46 , Ps.db); pseudepiphallic sclerite inner bars forming a dorsal arc, with each bar projected straight to the median region, and not fused with each other ( Fig. 43 , Ps.ib). Ectophallic invagination: ectophallic lateral bar slightly inclined ( Figs 45 , Ect.lb). Endophallus: apodeme a little more dilated ( Fig. 45 , End.Sc.a, yellow arrow indicates the apodeme).

Variations in phallic sclerites (paratypes, n = 3, ISLA 43342; 77745 and 77746; Figs 78–80, 84–86 ). It presents the same types of variations highlighted for the size and the ectophallic apodeme (Ect.Ap) in E. (P.) didymu s n. sp. Furthermore, the internal angle average of the pseudepiphallic dorsal branch calculated from the proximal to the distal portion, close to sixty degrees (59.55° ± 3.29°) ( Figs 78–80 ); dorsal field of pseudepiphallic arm pronounced (0.056 mm 2 ± 0.013 mm 2, n = 3) ( Figs 84–86 ).

Male right tegmen ( Figs 54-59 ). Stridulatory file with 67 ± 6.4 teeth (n = 6); mirror: relatively conserved in this species ( Figs 61–63, 65 ); however, a small cell within the second distal cell may be present ( Fig. 64 ); harp: one to two poorly marked diagonal veins may be present among cells or ramifying the main crossvein, in the first distal or proximal cells ( Figs 61–62, 64–65 ); three to four well marked crossveins; basal field: one to two vertical or diagonal crossveins can be present, forming two small cells jointed with CU 2 ( Figs 63–64 ); reticular branches can be present between the veins 1A and 2A; lateral field: with well marked accessory crossvein bifurcated ( Figs 61, 64–65 ) or with many reticular veins distributed between well-marked veins ( Figs 62–63 ).

Female: same size and coloration to the male (µ = 19.97 mm ± 0.38 mm; n = 2) ( Fig. 99 ); supranal and subgenital plate whitish ( Figs 67 – 68 ); ovipositor shorter than the cerci (µ = 11.131 mm ± 0.221 mm) ( Figs 66 – 70 ); the other structures have the same morphology observed to the females of E. (P.) didymus n. sp. Female genitalia ( ISLA 43343). Copulatory papilla of similar morphology compared to E. (P.) didymus n. sp. ( Fig. 71 ).

Variations in copulatory papilla (paratypes, n = 2, ISLA 46634 and 77747) similar to that observed in E. (P.) didymus n. sp. ( Figs 72 – 73 ).

Courtship song of Endecous troglobius n. sp. ( Fig. 74 , Tab. 3). Male sends intermittent phrases composed of 4 to 30 subphrases, varying from 4.6 to 43s, respectively, and subphrases ranging from 0.011 to 0.078s; the subphrase period range from 0.9 to 2.3s; and the number of sound waves show high variation comparing first and second pulses of the subphrase, 24–61 and 32–60, respectively.

Chromosomes of E. troglobius n. sp. ( Fig. 36 ; Tab. 4). Diploid chromosome number of 2n = 21, X0 ♂ /XX ♀, with the same chromosome morphology as E. (P.) didymus n. sp. as well as in secondary constrictions position and satellite size. There is same minor variation in the centromeric index among new species.

Male and Female measurements. Tables 2 and 4.

Figures

FIGURE 1 (A and B). (A) Type locality of Endecous species from South America (excepting Minas Gerais State); (B) Type locality of Endecous species from Minas Gerais State. (*) Uncertain locality, possibly between the border between the States of Minas Gerais and Bahia, described for the first time as “Sierra Geral”.

FIGURE 107. Schematic distribution map of Endecous (Pedroecous) didymus n. sp. and Endecous (Pedroecous) troglobius n. sp. in the Lapa Sem Fim cave.

FIGURE 34, 74. Courtship song of new species of Endecous. 34. Endecous (Pedroecous) didymus n. sp.. (A) spectrogram of phrase with 12 subphrases, (B) Oscillogram of a phrase; 74. Courtship song of Endecous (Pedroecous) troglobius n. sp. (A) spectrogram of phrase with 10 subphrases, (B) Oscillogram of a phrase.

FIGURES 75–86. Morphological variations in phallic sclerites of new species of Endecous. 75–77, 81–83. Endecous (Pedroecous) didymus n. sp. (ISLA 43329, 43336* and 43338) in dorsal and dorsal view tilted posteriorly, respectively. 78–80, 84–86. Endecous (Pedroecous) troglobius n. sp. (ISLA 77745; 43342* and 77746) in dorsal and dorsal view tilted posteriorly, respectively. Legend: dashed red line indicates the internal angle average of the pseudepiphallic dorsal branch; the angle was calculate in ventral view, from the basal distance of the extension of the Ps.db with respect to the apical portion; blue slice indicate the area (mm²) of pseudepiphallic arm “field”, calculated in dorsal view, inclined posteriorly; *phallic complex used in description of new species.

FIGURES 87–88. Endecous (Pedroecous) didymus n. sp. and Endecous (Pedroecous) troglobius n. sp. in frontal view, in vivo, with emphasis on the ommatidia pigmentation.

FIGURES 96–101. Endecous (Pedroecous) new species found in the Lapa Sem Fim cave. 96, 98 and 100–Endecous (Pedroecous) didymus n. sp. 96–adult ♂; 98–adult ♂ and ♀ interacting (probably some sexual behavior); 100–female nymph of Endecous (Pedroecous) didymus and Endecous (Pedroecous) troglobius n. sp. in the overlap zone. 97, 99 and 101—Endecous (Pedroecous) troglobius n. sp. 97 and 99–adult ♂ and ♀, respectively; 101–nymph feeding on frugivorous bat guano.

FIGURES 8-15. Endecous (Pedroecous) didymus n. sp. holotype morphology. 8–9, head in front, lateral and dorsal view, respectively; 10–pronotum, dorsal view; 11–right tegmen, dorsal view; 12–right tegmen and pronotum, lateral view; 13–subgenital and supranal plate, phallic sclerite, lateral view; 14–subgenital plate, ventral view; 15–supranal plate, dorsal view. Conventions: m., mirror; h., harp; b.f., basal field; l.f., lateral field.

FIGURES 16-19. Endecous (Pedroecous) didymus n. sp. holotype’s legs morphology. 16–leg III, subapical and apical spurs, outer view; 17–leg III, subapical and apical spurs, inner view; 18–leg I (outer view) and leg II (outer view, little spur (λ) apex of the tibia); 19–leg I (inner view and tympanum) and leg II (inner view, little spur (μ) apex of the tibia).