Schistocerca cohni Song

Song, Hojun, 2006, Description of Schistocerca cohni n. sp. and redescription of S. socorro (Dirsh) (Orthoptera: Acrididae: Cyrtacanthacridinae) from Mexico, Zootaxa 1150, pp. 43-52 : 44-47

publication ID	https://doi.org/ 10.5281/zenodo.172138
DOI	https://doi.org/10.5281/zenodo.6261595
persistent identifier	https://treatment.plazi.org/id/03CB87E4-FFBF-9533-FEEF-FA090F69FD26
treatment provided by	Plazi
scientific name	Schistocerca cohni Song
status	sp. nov.

Treatment

Schistocerca cohni Song n. sp.

( Figs. 1 View FIGURE 1 A–1J, 3A)

Male. Medium size (total length = 39.2± 3.15 mm; hind femur length = 20.13± 1.87 mm; pronotum length = 6.97± 0.6 mm (n = 6)).

Antennae much longer than the combined length of head and pronotum. Integument highly setose. Setae on pronotum, sternum, abdomen and femora long. Median carina of pronotum distinct and slightly raised, but not constricted. Sulci distinct, but not deep. Sculpting pattern of dorsal surface of prozona papillulate. Lateral lobes of prozona slightly wrinkled. Hind angle of pronotum slightly obtuseangular. Small granules present on pronotum and thorax. Anterior and posterior portion of pronotum similar width. Tegmina slightly extending beyond the tip of abdomen. Cerci quadrate, with length twice longer than width ( Fig. 1 View FIGURE 1 J). Apical tip of cercus slightly bilobed, with lower part extruding more than upper. Furcula small and rectangular. Epiproct with a pair of tubercle absent ( Fig. 1 View FIGURE 1 H). Subgenital plate with round apex ( Fig. 1 View FIGURE 1 I). Apical lobes of subgenital plate not outwardly flared, with Ushaped notch.

Color: Rusty brown to slightly deep olive green. Head rusty brown to deep olive green with faint to strongly dark subocular stripes. A pair of dark brown stripes between eyes from upper half of frontal ridge to occiput, often extending to pronotum. Head, pronotum and tegmina with a bright yellow dorsal longitudinal stripe. Lateral lobes of pronoza without marking. Metazona with granules. Epimeron without marking. Tegmina uniformly brown. Tegminal veins brown. Hind wings with slightly yellow tinge. Posterior margin of abdominal tergites with a row of black dots. Dorsal and ventral surface of hind femora light brown to olive green. Hind femora mostly without dorsal bands, but sometimes with a trace. Medial area white. Carinula with a row of very small black dots. Upper and lower carina without dots. Hind tibiae dark reddish brown to black, with tibial spines yellow with a black tip.

Phallus: Cingulum , surfaces of rami slightly infolded in the middle and somewhat convex, thus making “basal eminence” appear slightly bilobate and somewhat constricted in the middle ( Figs. 1 View FIGURE 1 C & 1E). Endophallus, basal valves ventral angle protruding more than dorsal, valves of cingulum clubshaped and curved downward, protruding more than apical valves of aedeagus ( Fig. 1 View FIGURE 1 G). Epiphallus, distance between lophi longer than the length of base of a lophus ( Fig. 1 View FIGURE 1 F). Lophi lamelliform.

Female. Much larger than male (total length = 59.37± 3.27 mm; hind femur length = 29± 1.91 mm; pronotum length = 10.83± 0.6 mm (n = 3)). Median carina of pronotum more raised. Otherwise same as male.

Type. Holotype male ( Fig.3 View FIGURE 3 A). Mexico: Guerrero: 9 rd. mi. NE. Taxco (1.7 rd. mi. SW. Acuitlapan) 5700 ft. 17 Sep 1959, I.J.Cantrall & T.J.Cohn, #137 (deposited at University of Michigan Museum of Zoology).

Collecting Localities. Eight paratypes (ɗ: 5, Ψ: 3) from UMMZ. Mexico: Guerrero: 9 rd. mi. NE. Taxco (1.7 rd. mi. SW. Acuitlapan) 5700 ft. 17 Sep 1959, I.J.Cantrall & T.J.Cohn, #137 (2 ɗ + 1 Ψ); Jalisco: 12.4 mi. N. Barra de Navidad (on Hwy 80) 5 Oct 1970, T.J.Cohn & J.W.Cohn, #43 (2 ɗ); Oaxaca: 2.5 mi. E. La Ventosa (12 mi. NE Juchitán) 150 ft. 13 Sep 1959, I.J.Cantrall & T.J.Cohn, #107 (1 ɗ); Puebla: 3 mi. SE. Petlalcingo 4900ft. 15 Sep 1959, I.J.Cantrall & T.J.Cohn, #126 (1 ɗ); San Luis Potosi: El Pujal. 100 ft. 18 Jul 1939, R.Haag (1 Ψ).

Diagnostic Characters. Schistocerca cohni has a bright yellow dorsal stripe from head to tegmina. Antennae are much longer than the combined length of head and pronotum, especially in males. It can be easily distinguished from the species in the Alutacea Group on the basis of male epiproct ( Fig. 1 View FIGURE 1 H), which lacks a pair of tubercles and the male subgenital plate ( Fig. 1 View FIGURE 1 I) which is not flared outwardly.

Biology. Not much is known about S. cohni . The specimens were collected from open woodlands with a thick growth of mediumheight weeds. Nothing is known about its feeding preferences, but the overall ecology and behavior are likely to be similar to other species in the Alutacea Group.

Taxonomic Discussion. This species was initially discovered during a morphological phylogenetic analysis of Schistocerca ( Song 2004a) . The specimens were identified by Dirsh as S. obscura (Fabricius) , but they clearly lacked a characteristic subgenital plate of S. obscura . Further examinations on both internal and external morphological structures revealed that it was a new species overlooked by previous taxonomists. The collecting localities ( Figure 3 View FIGURE 3 A) indicate that this species is widespread in various habitats. Song (2004a) found that S. cohni (S. new sp. in Figure 2 View FIGURE 2 ) is phylogenetically closely related to the species in the Alutacea Group. In fact, this species possesses all the synapomorphies uniting the Alutacea Group, namely, round subgenital plate, quadrate cerci, pronotal granules, and constricted zygoma ( Song 2004b). Schistocerca cohni is superficially similar to S. lineata , but has a distinctly different epiproct where a pair of tubercles is absent. This loss character is also found in S. albolineata and S. obscura , but S. cohni is distinct from these two species because the apical lobes of subgenital plate are not flared outwardly.