Melanoplus nelsoni, Hill, 2023

Hill, JoVonn G., 2023, Diversification deep in the heart of Texas: seven new grasshopper species and establishment of the Melanoplus discolor species group (Orthoptera, Acrididae, Melanoplinae), ZooKeys 1165, pp. 101-136 : 101

Melanoplus nelsoni sp. nov.

Figs 2A , 3A , 4A , 6A-H , 14 , 16

Type material.

Holotype. 1♂, USA, TX, Bell Co., 1.7 mi N Ding Dong, 30.9969, -97.7861, 4 October 2019, J.G. Hill, MJT, BSD; Collected in open Ashe juniper woodland; MEM 281,626. Deposited in the Mississippi Entomological Museum.

Specimens examined.

Texas: Bell Co., 1.7 mi N Ding Dong , 30.9969, -97.7861, 4 October 2019, J.G. Hill and M.J. Thorn (3♂, 5♀) , 3 mi W Killeen, Hood Village , 26 August 1955, T.J. Cohn (2♂) . Burnet Co., 6 mi E Burnet , 9 July 1959, T.J. Cohn (3♂) ; 2 mi W Joppa , 30.8298, -98.0608, 13 July 2020, J.G. Hill (8♂, 2♀) .

Diagnosis.

Easily differentiated from the other species in the group based on the male cerci which are subquadrate (Figs 2A , 6A, B ) and by the male aedeagus, which has lightly sclerotized dorsal valves that are deeply forked and with the apices of the medial fork produced as a filament tail that is almost two times as long as the lateral branch and curves anteriorly (Fig. 6E ). Most similar to M. discolor , but M. nelsoni is easily distinguished from that species by having shorter more quadrate male cerci and much longer filamentous tails on the dorsal valves (Fig. 6C-G ).

Measurements.

Male measurements. (mm): (n = 12) Body length 15.5-22.5 (mean = 20.1); pronotum length 3.3-5.1 (mean = 4.3); tegmen length 4.6-7.1 (mean = 5.7); hind femur length 9.0-12.3 (mean = 11.0); cerci length 0.7-1.0 (mean = 0.9); basal width of cercus 0.5-1.0 (mean = 0.8); mid-cercal width 0.5-0.6 (mean = 0.6); cerci apex width 0.3-0.4 (mean = 0.4).

Female measurements. (mm): (n = 9) Body length 19.5-24.0 (mean = 21.6); pronotum length 4.2-5.7 (mean = 5.0); tegmen length 5.5-7.5 (mean = 6.5); hind femur length 10.5-14.0 (mean = 12.4) Dorsal ovipositor valve length 1.0-1.5 (mean = 1.3); ventral ovipositor valve length 1.0-1.5 (mean = 1.3).

Habitat.

Ashe juniper savannas with short vegetation, exposed rocks, and bare ground (Fig. 16A ).

Distribution.

The northeastern Edwards Plateau in Bell and Burnet Counties, Texas (Fig. 14 ).

Etymology.

Named in honor of Willie Nelson, an iconic American musician entertainer from central Texas whose music lifted our spirits while traveling between field sites during this study. After these last few summers, just like Mr. Nelson, we too have a little Texas in our souls.

Suggested common name.

Nelson’s pouncer.

Figures

Figure 2. Lateral outlines of the male cerci of species in the Melanoplus discolor species group A M. nelsoni B M. discolor C M. corniculatus D M. Melanoplus walkeri E M. walkeri F M. susdentatus G M. kendalli H M. tonkawa I M. comanche.

Figure 3. Lateral views of the male aedeagus of species in the Melanoplus discolor group. DV: dorsal valve, S: sheath, VV: ventral valve. A M. nelsoni B M. discolor C M. corniculatus D M. comanche E M. kendalli F M. susdentatus G M. walkeri H M. tonkawa I M. balcones.

Figure 4. Dorsal views of the male aedeagus of species in the Melanoplus discolor group. DV: dorsal valve, S: sheath, VV: ventral valve. A M. nelsoni B M. discolor C M. corniculatus D M. comanche E M. kendalli F M. susdentatus G M. walkeri H. M. tonkawa I M. balcones.

Figure 6. Melanoplus nelsoni sp. nov. A dorsal view of male terminalia B lateral view of male terminalia C dorsal view of phallic complex D lateral view of phallic complex E dorsal view of aedeagus F lateral view of aedeagus G caudal view of the aedeagus H dorsal view of epiphallus I caudal view of epiphallus J habitus.

Figure 14. Distribution of species in the Melanoplus discolor group A broad view of the group, showing the wide distribution of M. discolor B distribution of Melanoplus discolor group species occurring in central Texas with the Balcones Escarpment indicated.

Figure 16. Habitat and live images of Melanoplus nelsoni sp. nov. A Ashe juniper savanna, Burnett County, Texas B male C female D male.