Euconnus falcatus, Caterino, 2022

Caterino, Michael S., 2022, First report of the Euconnus Thomson subgenus Cladoconnus Reitter in the New World, represented by thirteen new Appalachian species (Coleoptera, Staphylinidae, Scydmaeninae), ZooKeys 1137, pp. 133-175 : 133

Euconnus falcatus sp. nov.

Figs 9 , 10A, B , 11

Type material.

Holotype ♂, deposited in FMNH: "USA: NC: Swain Co., 35.5566°N, 83.4966°W, SmokyMts NP, 6272', Clingmans Dome, sifted litter, ix.14.2021, M.Caterino & E.Recuero" / "[QR code] CLEMSON-ENT CUAC000156725" / "Caterino DNA Voucher Extraction MSC7899, Morphosp. CD.B.307". Paratypes (40, CUAC, CNCI, FMNH, UNHC) - 1 ♂: "USA: NC: Swain Co., 35.5613°N, 83.5006°W, SmokyMts NP, 6364', ClingmansDome, W. slope, sifted litter, vi.5.2018, M.Caterino" / "[QR code] CLEMSON-ENT CUAC000079152" / "Caterino DNA Voucher Extraction MSC2834 Morphosp. CD.A.021"; 1 ♀, 3 ♂: "USA: NC: Swain Co., 35.5824°N, 83.3979°W, SmokyMtsNP,offHwy 441, 4610', iii.12.2020, M.Caterino & F.Etzler, sifted litter"; 1 ♀: "USA: TN: Swain Co., 35.6237°N, 83.4163°W, SmokyMtsNP,offHwy 441, 4575', iii.12.2020, M.Caterino & F.Etzler, sifted litter" / "[QR code] CLEMSON-ENT CUAC000110837" / "Caterino DNA Voucher Extraction MSC4193 Morphosp. Hwy.A.006"; 1 ♀, 8 ♂: "USA: TN: Sevier Co., 35.6160°N, 83.4149°W, SmokyMts NP, 5456', App.Tr. E of Newfound Gap, sifted litter, vi.5.2018, M.Caterino"; 2 ♀, 9 ♂: "USA: TN: Sevier Co., 35.6308°N, 83.3904°W, SmokyMts NP, 6190', Mt. Kephart, vi.5.2018, M.Caterino"; 1 ♂: "USA: TN: Sevier Co., 35.6311°N, 83.3895°W, SmokyMts NP, 6183', Mt. Kephart,sifted litter, vi.5.2018, M.Caterino" / "[QR code] CLEMSON-ENT CUAC000079110" / "Caterino DNA Voucher Extraction MSC2790 Morphosp. MK.A.009"; 1 ♂: "USA: TN: Sevier Co., 35.6311°N, 83.3893°W, SmokyMts NP, 6187', Mt. Kephart, sifted litter, ix.14.2021, M.Caterino & E.Recuero" / "[QR code] CLEMSON-ENT CUAC000156767" / "Caterino DNA Voucher Extraction MSC7941 Morphosp. MK.B.482"; 4 ♀, 4 ♂: "USA: TN: Sevier Co., 35.6425°N, 83.4427°W, SmokyMts NP, 5196', Alum Cave Tr., vi.25.2019, M.Caterino & M.Ferro, sifted mixed litter"; 1 ♂: "USA: TN: Sevier Co., 35.6529°N, 83.4378°W, SmokyMts NP, 6467', Mt LeConte, vi.25.2019 M.Caterino & M.Ferro, sifted conifer litter" / "[QR code] CLEMSON-ENT CUAC000079302" / "Caterino DNA Voucher Extraction MSC3483 Morphosp. MLc.009"; 1 ♀, 1 ♂: "USA: TN: Sevier Co., 35.6541°N, 83.4364°W, SmokyMts NP, 6588', Mt LeConte, ix.28.2021, M.Caterino, sifted litter"; 1 ♂: "NC Gr.Sm.Mts.N.P., Clingmans Dome, 1950-2020m 2.VI.86 A.Smetana" (CMNC); 1 ♂: "TENN:Great Smoky Mts.St.Pk.: Newfound Gap" / "X.24.1969 W.Shear + F.Coyle leg." / "FM(HD) 69-62 Spruce litter" (FMNH).

Other material.

(36, CUAC, UNHC, CNCI) - NC: Haywood Co., Pisgah National Forest , Black Balsam Knob, 6033-6072ft, 7-May-2018 & 20-Oct-2020 (3 ♂) ; Haywood Co., Pisgah National Forest , Mountains to Sea Trail, 5540ft., 8-Sep-2020 (1 ♂) ; Haywood Co., Blue Ridge Parkway National Park, Mt. Pisgah, 5420ft., 13-Sep-2022 (1 ♀, 1 ♂) ; Jackson Co., Blue Ridge Parkway National Park, Mt. Lyn Lowry, 6097 ft., 15-Jun-2021, sifted litter (1 ♀) ; Jackson Co., Blue Ridge Parkway National Park, Mt. Lyn Lowry, 6205 ft., 22-Sep-2020, sifted litter (1 ♀) ; Jackson Co., Blue Ridge Parkway , National Park , along Blue Ridge Pkwy, 5572ft., 11-Sep-2019 (1 ♀, 1 ♂) ; North Carolina , Jackson Co., Blue Ridge Parkway National Park , Browning Knob, 6140-6221, 22-Sep-2020 & 29-May-2018 (3 ♀, 1 ♂) ; Jackson Co., Blue Ridge Parkway National Park , Waterrock Knob, 6059, 29-May-2018 (4 ♀, 4 ♂) ; Jackson Co., Blue Ridge Parkway National Park , Waterrock Knob , 6281, 29-May-2018; Jackson Co. , Balsam Mountain Preserve , Doubletop Mountain, 5396-5480, 7-Feb-2015 & 15-Jun-2015 (4 ♂) ; Jackson Co., Nantahala National Forest, Toxaway Mt., 4750, 5-Aug-2020 (1 ♂) ; Jackson Co., Wolf Mt. overlook, 26-May-1986 (3 ♂) ; Jackson Co., Blue Ridge Parkway National Park , 5572, 11-Sep-2019 (1 ♀) ; Macon Co., Nantahala National Forest , Copper Ridge Bald, 5144, 9-Jul-2019 (1 ♂) ; Macon Co., Hwy. 64, nr. Dry Falls, 16-May-1986 (2 ♀, 1 ♂) ; Macon Co., Coweeta Hydrological Lab , Shope Fork, 3200, 28-May-1983 (1 ♂) .

Description.

Body rufescent (Fig. 9A-D ), weakly translucent; head and elytra sparsely setose, pronotum densely setose, especially at sides; head with frons weakly depressed between antennal bases (Fig. 9H ), vertex convex, neck just over one-half maximum head width; eyes of male moderately large, protuberant, comprising ca. 15 distinct ommatidia (Fig. 9H ), situated immediately behind antennal insertions, width slightly more than that of tempora behind; eyes of female smaller (Fig. 9G ), less prominent, comprising <8 ommatidia, width only one-third that of tempora; antennae inserted under blunt frontal shelf; antennae of male with scape and pedicel similar in length, ca. twice length of antennomeres III-VI, antennomere VII slightly larger, asymmetrical, slightly produced on anterior margin, antennomeres VIII-XI distinctly larger, antennomeres VIII and IX with longitudinal carinae on anterior margin (Fig. 9E ), that of VIII more or less parallel to antennal axis, that of IX more strongly produced at apex, antennomeres VIII-X similar in length, terminal antennomere ca. twice as long; female antennae shorter, club composed of only three short, wide antennomeres (Fig. 9D, G ); pronotum weakly bell-shaped, with sides arcuate (Fig. 9F ), widest ca. one-fourth behind straight anterior margin, narrowed posteriorly, similar in width to anterior, with short longitudinal carinae on either side, transversely depressed between, with small submedian foveae on either side of low median ridge (median basal carina absent), and two small foveae outside lateral carina, pronotal sides very densely bristled; mesoscutellar shield hidden; elytra broadly rounded, widest just anterad middle, each with two small basal foveae, sparse setae randomly arranged; flight wings poorly developed or absent in both sexes; abdominal ventrites without secondary sexual differences; aedeagus (Fig. 10A ) broadly rounded basally, apex of median lobe narrowed, pinched before apex, subtruncate; parameres thin, close to median lobe, with two long apical setae extending beyond median lobe apex; dorsal diaphragm crescent-shaped; compressor plate thin, narrowly rounded at apex, slightly asymmetrical; endophallus with two asymmetrical primary sclerites, an upper one almost linear, weakly sinuous to acute apex, the lower one strongly sickle-shaped, bearing a single conspicuous and sometimes an additional small secondary processes on its inner surface.

Distribution.

Euconnus falcatus exhibits a wide distribution, especially considering its flightlessness, including the Great Smoky Mountains, continuing along the high Blue Ridge Parkway corridor into the Plott Balsams and Great Balsams, as well as slightly lower parts of the Nantahala and Cowee Mountains. In elevational range it occurs from 3200 ft at Coweeta to its highest occurrences on Clingmans Dome and Mt. LeConte above 6500 ft.

Remarks.

A more complete description of this species is provided to serve as a general description for several subsequent species that differ in few or no obvious external characters, including E. cataloochee , E. kilmeri , E. draco , E. tusquitee , E. attritus , E. cultellus , E. adversus , and E. astrus . The modified male antennomeres differ significantly in a couple of these ( E. adversus and E. astrus ), but only slightly or not at all in the others. Euconnus falcatus can only be unambiguously distinguished from the others by male genitalic characters. Specifically, the lower endophallic sclerite is long, sickle-shaped, and bears a small secondary hook near its midpoint. The apex of the median lobe is more narrowly knobbed than most others, and the apex of the compressor plate is only subtly asymmetrical. There appear to be some differences in exact shapes of endophallic sclerites among localities (e.g., Fig. 10B ). Some of this variation may be real, but some also appears to result from varying degree of extroversion of the lower hooked sclerite relative to the upper one.

This species name refers to the distinctively ‘sickle-shaped’ hook of the endophallic armature.

Figures

Figure 9. Habitus and character photos of Euconnus falcatus A male, lateral view B female, lateral view C male, dorsal view D female, dorsal view E SEM, male antenna F SEM, pronotum and elytra G SEM, female head, lateral view H SEM, male head, anterior view.

Figure 10. Aedeagus. A Euconnus falcatus B compressor plate and upper endophallic armature of Euconnus falcatus (Plott Balsams variant) C Euconnus cataloochee D Euconnus kilmeri.

Figure 11. Map of collecting records for Euconnus (Cladoconnus) falcatus complex. E. (C.) falcatus (circles), E. (C.) cataloochee (stars), E. (C.) tusquitee (triangules), E. (C.) draco (hexagons), E. (C.) kilmeri (plus sign), and E. (C.) attritus (x).