Sphenarium zapotecum Sanabria-Urbán, Song & Cueva

Sanabria-Urbán, Salomón, Song, Hojun, Oyama, Ken, González-Rodríguez, Antonio & Castillo, Raúl Cueva Del, 2017, Integrative taxonomy reveals cryptic diversity in neotropical grasshoppers: taxonomy, phylogenetics, and evolution of the genus Sphenarium Charpentier, 1842 (Orthoptera: Pyrgomorphidae), Zootaxa 4274 (1), pp. 1-86 : 29-31

Sphenarium zapotecum Sanabria-Urbán, Song & Cueva del Castillo sp.n.

(http://lsid.speciesfile.org/urn:lsid: Orthoptera .speciesfile.org:TaxonName:495075)

Description. External morphology ( Fig. 9 G, H): total body length ranging from 22.13 to 26.73 mm in females and from 19.29 to 24.26 mm in males; antennae filiform, slightly shorter in females or longer than head and pronotum together in males; head subtriangular-elongated slightly longer than wide in females or conical notably longer than wide in males, with oval eyes in both sexes; fastigium moderately elongated, nearly half the length of interocular space in females or notably elongated, nearly as long as the interocular space in males; tegmina spatula-like in both sexes; subgenital plate of males rounded, moderately developed posteriorly; dorsal ovipositor valves lanceolate, moderately elongated towards the apex. Male genitalia: bridge of epiphallus as long or slightly longer than the length of lateral plates in most cases ( Fig. 10 J–I). Ectophallus in dorsal view ( Fig. 10 J-II) with lateral borders convergent slightly rounded; basal emargination of cingulum moderately developed; interspace between apodemal plates of cingulum moderately open. Ectophallus in posterior view ( Fig. 10 K) without a conspicuous sclerotized hollow in the sheath; inflections of supraramus reduced or not developed laterally ( Fig. 10 K, arrow); valves of cingulum with unique tongue-like form, notably developed posteriorly ( Fig. 10 L). Endophallus in lateral view ( Fig. 10 J-III) with an elongated pseudoarch loosely joined to the valves of cingulum; aedeagal valves long with smooth ventral borders and an apical spine slightly longer than the width of the base of aedeagal sclerites; aedeagal valves and sclerites together about twice the length of dorsal inflections of endophallic apodemes.

Colouration. Ground colours varying from green to brown. Body uniformly coloured with ground colours ( Fig. 9 H) or with the following colour traits ( Fig. 9 G): antennae generally light brown; fastigium brown to black; lateral postocular bands whitish; dorsomedial line narrow and pinkish in eastern populations or wide and yellowish in western populations; dorsal shades black, grey or brown, frequently covering partially the dorsal portion of the body; lateral black shades generally absent or restricted to head; lateral bands of blotches not evident; ventral bands of pronotum generally absent, instead ventral borders of pronotum lightly-coloured; mesonotum partially or entirely black; lateral blotches of 1st abdominal segment if present white; hind femora uniformly coloured with knees laterally black, dorsally brownish; hind tibia orange.

Diagnosis. Externally this species closely resembles S. purpurascens and S. variabile . However, S. zapotecum sp.n. generally differs from these two species by its more elongated head in both sexes. At the male genitalia level S. zapotecum sp.n. more closely resembles S. purpurascens and S. tarascum sp.n., which also show an apical spine in the aedeagus and lack the sclerotized hollow in the sheath of ectophallus. Nevertheless, S. zapotecum sp.n., differs from these latter species by its reduced or undeveloped inflections of supraramus, as well as the unique form of its valves of cingulum notably projected posteriorly.

Distribution. This species is apparently restricted to the outer southern slope of the Sierra Madre del Sur in Oaxaca, Mexico, occurring in elevations ranging from 1016 to 1457 m a.s.l. ( Fig. 7 B, C).

Material examined. Holotype m ( Figs. 9 G; 10J, K, L) from Mexico: Oaxaca, Pluma Hidalgo (1), 15.93987876°N, - 96.42996051°W, 1153 m a.s.l., XII-11-2013 (Sanabria-Urbán S., Fontana P. & Mariño-Pérez R. #L27); measurements: BS = 23.74 mm, FL = 1.29 mm, PL = 4.68 mm, HF = 11.77 mm. Paratypes from Mexico: Oaxaca: 4 m, 3 f, same data as holotype ; 2 m, 2 f, Carr. 175 Km. 172, XII-12-2013, 16.01864845°N, - 96.5303105°W, 1457 m a.s.l. (Sanabria-Urbán S., Fontana P. & Mariño-Pérez R. #L31); 1 m, Oaxaca road ca. 85km N Pto. Angel , IX-1-1981 (Otte, Azuma & Newlin # 43) ; 2 m, 1 f, 24-25 mi. N Pto. Escondido rd. to Oaxaca, IX-2- 1981 (Otte, Azuma & Newlin # 45). The holotype was deposited at IBUNAM and the paratypes were deposited at the ANSP, IBUNAM and TAMUIC. Additional material: 5 m, 4 f, from three additional localities (Appendix Table 5).

Taxonomic discussion. We observed that S. zapotecum sp.n. is mainly related morphologically and genetically to S. purpurascens . Nevertheless, its unique combination of morphologic traits (both in external and male genitalia structures), as well as its geographic isolation supports its recognition as an independent species within the genus. Sphenarium zapotecum sp.n. was not included in previous studies on the genus except for Pedraza-Lara et al. (2015), who identified specimens from a locality within the ranges of this new species as Sphenarium sp. Oax6. Using the CO1 sequences of Pedraza-Lara et al. (2015) and the present study, the only locus represented in both studies, we conducted a combined Bayesian phylogenetic analysis, in which all Sphenarium sp. Oax6 samples strongly clustered (PP> 0.95) with S. zapotecum sp.n. samples ( Fig. 11 ). Considering their geographical and phylogenetic proximity it is probable that Sphenarium sp. Oax6 and S. zapotecum sp.n. represent the same species.

Etymology. Named in honour of the Zapotecos, an ancient Native American people still living in the area where this species is distributed.

Figures

FIGURE 7. Geographic distribution of Sphenarium species. Numbers within parenthesis in front of taxa names indicate the number of identified morphotype within the species. White surrounded areas and upper case abbreviations denote the Mexican biogeographic provinces. AC, Altos de Chiapas; AL, Altiplano Sur; BRB, Balsas River Basin; GMC, Gulf of Mexico Coast; MVB, Mexican Volcanic Belt; PC, Pacific Coast; SMOC, Sierra Madre Occidental; SMOR, Sierra Madre Oriental; SMS, Sierra Madre Sur; SO, Soconusco; and SOX, Sierra de Oaxaca.

FIGURE 9. External morphology of S. purpurascens: morphotype 1 m (A) and f (B), morphotype 2 m (C) and f (D), and morphotype 3 m (E) and f (F); S. zapotecum sp. n. holotype m (G) and paratype f # 23 (H); S. tarascum sp. n. holotype m (I) and paratype f # 2 (J,); S. planum m (K) and f (L); S. macrophallicum paratype m # 230 (M) and f (N); S. minimum m (O) and f (P); S. infernalis sp. n. holotype m (Q) and paratype f # 2 (R); S. rugosum morphotype 1 m (S) and f (T) (Scale bars = 1 cm).

FIGURE 10. Male genital structures of S. purpurascens: morphotype 1 (A – C), morphotype 2 (D – F), morphotype 3 (G – I); and S. zapotecum sp. n. holotype (J – l). For all taxa left squares show epiphallus (I) and ectophallus (II) in dorsal view, and endophallus in lateral view (III); meddle squares show ectophallus in posterior view; and right squares show a close up of ectophallus in lateral view (Scale bars = 1 mm).

FIGURE 11. Bayesian phylogeny of Sphenarium species based on CO 1 sequences of Pedraza-Lara et al. (2015) and this study. The analysis was conducted using the substitution model estimated previously and under the same conditions above specified for the concatenated phylogenetic analysis in methods section. Terminals of different colours represent the 17 recognized species in this study. Black dots behind the nodes indicate PP values greater than 95 %. Black bottom bars are equal to 0.04 substitutions per site.