Ligidium schultzi sp. nov.

urn:lsid:zoobank.org:act: E438B528-4175-4BF6-9308-EA9ECE8C9D41

Figs 14–15

Ligidium sp. 6 – Recuero & Caterino 2024: table 1.

non Ligidium elrodii – Schultz 1982: 14.

Diagnosis

This new species is characterized by the distally broadened male pleopod 2 endopodite, which presents on the caudal margin as a marked notch. Male pleopod 2 exopodite has its frontal margin concave. It also can be distinguished from all other Appalachian species based on molecular data, representing a distinct evolutionary lineage.

Etymology

The species is named after George A. Schultz, for his important contributions to our knowledge of the genus Ligidium in North America, and for being the first to illustrate this species from North Carolina.

Material examined

Holotype

USA – North Carolina • ♂; Swain Co., Great Smoky Mountains N.P., off Highway 441, Thomas Divide Trail; 35.5824° N, 83.3979° W; 1405 m a.s.l.; 12 Mar. 2020; M. Caterino and F. Etzler leg.; GenBank no: OR169857 (Cox1); USNM, CUAC000171290.

Paratypes

USA – North Carolina • 1 ♂; same data as for holotype; CUAC000171291 • 4 ♀♀; same data as for holotype; CUAC000171292 to CUAC000171295 .

Other material examined

USA – Georgia • 2 ♂♂; Towns Co., Brasstown Bald; 34.8782° N, 83.8108° W; 1347 m a.s.l.; 17 Nov. 2020; Caterino and F. Etzler leg.; CUAC000171279, CUAC000180791 • 1 ♀; same data as for preceding; CUAC000138052 – North Carolina • 1 ♂; Graham Co., Nantahala N.F., Huckleberry Knob; 35.3210° N, 83.9934° W; 1674 m a.s.l.; 4 May 2020; M. Caterino and F. Etzler leg.; CUAC000138050 • 1 ♀, Haywood Co., Balsam Mountain Trail; 35.6425° N, 83.2007° W; 1565 m a.s.l.; 5 Nov. 2020; M. Caterino and F. Etzler leg.; CUAC000138054 • 3 ♂♂; Macon Co., Highlands Biological Station, Coker Rhododendron Trail; 35.0558° N, 83.1840° W; 1191 m a.s.l.; 20 Jun. 2022; P. Marek and L. Kairy leg.; CUAC000171315, CUAC000171319, CUAC000171320 • 1 ♂; Macon Co., Nantahala N.F., Copper Ridge Bald; 35.3270° N, 83.3359° W; 1535 m a.s.l.; 15 Sep. 2020; M. Caterino and F. Etzler leg.; CUAC000171277 • 2 ♀♀; same data as for preceding; CUAC000171278, CUAC000138046 • 3 ♀♀; Macon Co., Nantahala N.F., Cowee Bald; 35.3270° N, 83.3359° W; 1503 m a.s.l.; 15 Sep. 2020; F. Etzler, A. Haberski and P. Wooden leg.; CUAC000138047, CUAC000171283, CUAC000171284 • 5 imm.; same data as for preceding; CUAC000171285 to CUAC000171289 • 2 ♂♂; Macon Co., Nantahala N.F., Van Hook Glade Campground; 35.0783° N, 83.245° W; 1018 m a.s.l.; 21 Jun. 2022; CUAC000171321, CUAC000171322 • 1 ♀; same data as for preceding; CUAC000171318 • 2 ♀♀; Transylvania Co., Pisgah Forest; 35.3291° N, 82.789° W; 910 m a.s.l.; 23 Dec. 2021; E. Recuero and P.C. Rodríguez-Flores leg.; CUAC000171302, CUAC000171303 • 1 ♀; Transylvania Co., Pisgah National Forest, Hwy 215; 35.2910° N, 82.9133° W; 1561 m a.s.l.; 8 May 2018; M. Caterino, R. Kucuk and L. Cushman leg.; CUAC000171304 • 2 ♂♂; same data as for preceding; CUAC000171305, CUAC000171306 • 1 ovi. ♀; Clay Co., Nantahala N.F., Tusquitee Bald; 35.1415° N, 83.7273° W; 1582 m a.s.l.; 6 Jul. 2021; M. Caterino and E. Recuero leg.; CUAC000165724. – South Carolina • 1 ♀; Oconee Co., Sumter N.F., Walhalla Hatchery; 34.9853° N, 83.0731° W; 765 m a.s.l.; 21 Jan. 2023; C.W. Harden leg.; CUAC000177091 • 1 ♂; same data as for preceding; CUAC000177092 – Tennessee • 1 ♂; Blount Co., Great Smoky Mountains N.P., Rich Mountain Gap; 35.645° N, 83.81° W; 600 m a.s.l.; 27 Oct. 2021; M. Caterino, A. Haberski and P. Wooden leg.; CUAC000171264 • 2 ♀♀; same data as for preceding; CUAC000171265, CUAC000171266 • 3 ♂♂; Sevier Co., Great Smoky Mountains N.P., off Highway 441; 35.6240° N, 83.4163° W; 1394 m a.s.l.; 12 Mar. 2020; M. Caterino and F. Etzler leg.; CUAC000138081, CUAC000171297, CUAC000171298 • 2 ♀♀; same data as for preceding; CUAC000171300, CUAC000171301 • 1 imm.; same data as for preceding; CUAC000171296.

Description

Body length of males 4.6–5.7 mm, of females 4.7–5.7 mm; width (at pereonite 4) of males 2.5–2.8, of females 2.6–2.9 mm. Color in ethanol (Fig. 14) dorsally brown with large off-white, a dark brown longitudinal medial stripe running from pereonite 1 to pereonite 7, frequently broadening caudally; pereonites with darker transverse bands in the caudal margin, frequently with clearer spots; epimera brown marbled with off-white, with large white spots at the base; pleonites brown with a pair of more or less defined off-white spots, paramedian in pleonites 1 and 2, more lateral in pleonites 3–5; telson with two white spots laterally, and a white anchor-shaped spot; head marbled brown, sometimes with white area above eyes; antennae brown, sometimes with large white spots in basal segments, and a white setae bundle in the flagellum; uropod brown, dorsally with inner part of basipodite white; pereopods brown and white, pleopod exopodites white, often with inner and frontal parts brown. Antennule (Fig. 15G) three-segmented; first segment about 1.7–1.8 times as long as wide, 2–3 spiniform setae in its distal border; second segment about 2.5–2.6 times as long as wide, bearing 2–3 strong spiniform setae in the distal border; third segment with blunt apex and 1 or no setae. Antennae (Fig. 15F) with 5 segmented peduncle, relative size of antennomeres 5>4>3=2>1; antennal flagellum with 10–12 articles. Dactylus of pereopods with outer claw longer than inner one; no sexual dimorphism observed in pereopods 1 (Fig. 15H) and 7 (Fig. 15I). Male pleopod 1 endopodite (Fig. 15A) with narrow projection obliquely truncated distally, bearing 2 strong, blunt setae, up to 1.2 times as long as endopodite; part of caudal and inner margins with pilose setae. Pleopod 1 exopodite (Fig. 15B) with broadly rounded caudal margin bearing 2–3 strong, blunt setae, up to 0.5–0.7 times as long as exopodite; external margin with 2–3 very short but strong setae. Male pleopod 2 exopodite (Fig. 15C) 1.8–1.9 times as wide as long; inner, outer and part of frontal margin with dense, hairy setation; caudal margin strongly convex, with 2–4 very short, but strong setae; frontal margin concave. Male pleopod 2 endopodite (Fig. 15D–E) with unevenly rounded tip, presenting a marked notch or indentation; inner margin with minute spiniform setae denser near the base. Telson (Fig. 14) with caudal margin obtusely produced. Uropod (Fig. 15J) with long endopodite, 1.6–1.8 times as long as exopodite when not broken, and about 2.1–2.2 times as long as basipodite.

Distribution

The species is widely distributed in the southern part of the Blue Ridge Mountains, with all known records found west of the Asheville Depression (Fig. 14). Studied specimens have been collected in moist leaf litter from conifer, deciduous, and mixed forest, as well as under dead logs and stones, usually in damp places near streams. From 600 m to 1674 m a.s.l., most frequently above 1000 m.

Remarks

Ligidium schultzi sp. nov. corresponds with Ligidium sp. 6 in Recuero & Caterino (2024a). The shape of male pleopod 2 endopodite of this species was first illustrated by Schultz (1982), as a morphological variant of what he identified as L. elrodii, and indicated the need for further taxonomic study to determine the specific status. The new species is closely related to L. enotahensis sp. nov. and L. protuberans sp. nov. (Fig. 1A; see Remarks for those species). All three gene fragments analyzed are informative to identify this species, with high genetic p-distances among the mentioned taxa for Cox1, moderate for 28S and low for NaK (Supp. file 1), forming reciprocally monophyletic clades in all cases.