Sphenarium tarascum 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 : 31-32

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

(http://lsid.speciesfile.org/urn:lsid: Orthoptera .speciesfile.org:TaxonName:495095)

Description. External morphology ( Fig. 9 I, J): total body length ranging from 21.41 to 30.07 mm in females and from 19.44 to 25.6 mm in males; antennae filiform, slightly shorter in females or notably 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 are spatula-like in both sexes; subgenital plate of males rounded, moderately developed posteriorly; dorsal ovipositor valves lanceolate, notably elongated towards the apex. Male genitalia: bridge of epiphallus as long or slightly longer than the length of lateral plates in most cases ( Fig. 12 A-I). Ectophallus in dorsal view ( Fig. 12 A-II) with lateral borders of ramus convergent slightly rounded; basal emargination of cingulum moderately developed; interspace between apodemal plates of cingulum moderately open. Ectophallus in posterior view ( Fig. 12 B) without a conspicuous sclerotized hollow in the sheath; inflections of supraramus moderately developed with distal margins dorsally directed; valves of cingulum triangular to slightly quadrangular, moderately developed posteriorly ( Fig. 12 C). Endophallus in lateral view ( Fig. 12 A-III) with elongated pseudoarch, loosely joined to the valves of cingulum; aedeagal valves long with smooth ventral borders and an apical spine slender, slightly bent, and notably longer than the width of the base of aedeagal sclerites; aedeagal valves and sclerites together about 1½ fold the length of dorsal inflections of endophallic apodemes.

Colouration. Ground colours varying from green to brown; body uniformly coloured ( Fig. 9 J) or with the following colour traits ( Fig. 9 I): antennae brown to magenta; fastigium often reddish or brownish; lateral postocular bands yellowish; dorsomedial line frequently absent, if present very narrow, whitish, almost entirely restricted to the abdomen; dorsal shades brown, grey or magenta covering almost entirely the dorsal portion of thorax and abdomen, generally less evident in pronotum; lateral shades generally absent or restricted to head; lateral bands of blotches not evident; ventral bans of pronotum generally absent, instead ventral borders of pronotum lightly-coloured; mesonotum partially or entirely black; lateral blotches of 1st abdominal segment if present, whitish or yellowish; in most cases hind femora uniformly coloured with knees laterally brown, dorsally reddish; hind tibia sometimes brown or yellowish.

Diagnosis. Externally this species resembles other species with adjacent distribution, such as S. purpurascens , S. rugosum , and S. infernalis sp.n., as well as other more geographically distant species such as S. minimum and S. zapotecum sp.n. Generally, S. tarascum sp.n. differs from the first three species by its longer antennae, more elongated head (in both sexes) and dorsal ovipositor valves. The male genitalia of S. tarascum sp.n. more closely resemble those of S. purpurascens and S. zapotecum sp.n., which also have an apical spine in the aedeagus. However, S. tarascum sp.n., differs from these species by the following combination of male genital characters: lateral borders of ramus convergent slightly rounded, inflections of supraramus moderately developed and apical spine of aedeagus slender, slightly bent and longer than in any other species in the genus.

Distribution. This species is restricted north of the central portion of the Balsas River Basin in Michoacan, Mexico ( Fig. 7 A), in elevations ranging from 1394 to 1759 m a.s.l.

Material examined. Holotype m ( Fig. 9 I) from Mexico: Michoacan, Las Cañas sobre Carr. 120, 19.08443296°N, - 101.768692°W, 1394 m a.s.l., X-8-2015 (Sanabria-Urbán S. # M011-11ARO); measurements: BS = 22.19 mm, FL = 1.04 mm, PL = 4.31 mm, HF = 10.60 mm. Paratypes from Mexico: Michoacan: 9 m, 10 f same data as holotype; 3 m, 1 f, Rancho el Mirador, 19.20727001°N, -101.735125°W, 1759 m a.s.l., X-8-2015 (Sanabria- Urbán S. #M012). The holotype was deposited at IBUNAM and the paratypes were deposited at the IBUNAM and TAMUIC. Additional material: 5 m, 2 f, from the same locality as holotype but different date; and 3 m, 1 f, from two additional localities (see Appendix Table 5).

Taxonomic discussion. This species is closely related morphologically to S. purpurascens and genetically to S. rugosum . Nevertheless, its unique combination of morphologic traits (both in external and male genitalia structures), monophyly and geographic isolation supports its recognition as a separate species within the genus. Previously, we identified specimens of S. tarascum sp.n. as, Sphenarium sp.n. 5 ( Sanabria-Urbán et al. 2015). For other studies in the group this species was unknown.

Etymology. Named in honour of the Tarascos, an ancient Native American people still living in the area where this species was found.

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 12. Male genital structures of S. tarascum sp. n. holotype (A – C); S. planum (D – F); S. macrophallicum paratype # 234 (G – I); and S. minimum (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).