Anillinus seneca, Harden & Caterino, 2024

Harden, Curt W. & Caterino, Michael S., 2024, Systematics and biogeography of Appalachian Anillini, and a taxonomic review of the species of South Carolina (Coleoptera, Carabidae, Trechinae, Anillini), ZooKeys 1209, pp. 69-197 : 69-197

Anillinus seneca sp. nov.

Figs 12 D , 21 K , 24 J , 34 D , 35 D – F , 36

Type material.

Holotype male ( USNM): point mounted, with abdominal ventrites glued to point and genitalia in Euparal on microslide pinned beneath specimen. Original labels: “ USA: SOUTH CAROLINA, Oconee Co. Lake Hartwell, Martins Creek Landing , SW of Clemson. 34.6389, - 82.8656. 11 - January- 2020. C. W. Harden. Under embedded rocks in oak-hickory woods near lake. ” “ [QR Code] CLEMSON-ENT CUAC 000168244 ” “ Harden DNA Voucher CWH- 121 Anill. sp n ‘ martincrk’ Ext. 13 / May / 2020 [green-bordered cardstock] ” “ HOLOTYPE Anillinus seneca Harden & Caterino [orange cardstock] ”

GenBank: OR 853323, OR 839466.

Paratypes (n = 27; CMNH, CUAC, LSAM, USNM, VMNH). USA • South Carolina • 2 ♂, 2 ♀; same data as holotype; CUAC 000168247 , CUAC 000168248 , CUAC 000168250 , CUAC 000168242 ; CWH- 118, CWH- 120, CWH- 122, CWH- 124; CUAC ; • 1 ♂, 2 ♀; same locality as holotype; 4 Jan. 2020; C. W. Harden & L. M. Thompson leg.; soilwash flotation Berlese; CWH- 115 to CWH- 117, CUAC 000168239 to CUAC 000169241 ; CUAC ; • 2 ♂, 5 ♀; Oconee Co.; Martin Creek Landing ; 34.6388, - 82.8655; 15 May 2022; C. W. Harden and L. M. Thompson leg.; soilwashing; CMNH, USNM ; • 3 ♂, 2 ♀; Oconee Co.; Martin Creek Landing ; 34.6390, - 82.8638; 22 Oct. 2021; C. W. Harden leg.; under rock; LSAM, VMNH ; • 4 ♂, 4 ♀; Oconee Co.; South Cove Park ; 34.71165, - 82.96594; 30 Jan. 2020; C. W. Harden & L. M. Thompson leg.; Berlese, sifted soil / wood, pine stump near fishing pier; CWH- 338 to CWH- 345, CUAC 000168255 to CUAC 000168262 ; CUAC .

GenBank accession numbers for paratypes: OR 839463, OR 839465, OR 839467, OR 853324, OR 839469, OR 839460, OR 839461, OR 839462, OR 853327, OR 839630, OR 838053, OR 853328, OR 839631, OR 839632, OR 839633, OR 853326, OR 839621, OR 838050.

Other material

(n = 40 CUAC, CWHc). USA • South Carolina • 2 ♂; Anderson Co.; Clemson Experimental Forest, Big Oaks area near Lake Hartwell ; 34.60262, - 82.83858; 21 May 2020; C. W. Harden; Under embedded rock in clay soil; CWH- 161 and CWH- 162, CUAC 000168245 and CUAC 000168251 ; CUAC ; • 1 ♂, 1 ♀; Anderson Co.; Clemson Experimental Forest, Big Oaks area ; 34.60225, - 82.83893; 21 May 2020; C. W. Harden & L. M. Thompson; Berlese, deep soil by large stump near lake, after flood; CWH- 163 and CWH- 164, CUAC 000168252 and CUAC 000168253 ; CUAC ; • 1 ♂; Anderson Co.; River Forks Recreation Area ; 34.47497, - 82.80914; 19 Mar. 2021; C. W. Harden & L. M. Thompson; Berlese, sifted pine stump soil, near lake; CWH- 327, CUAC 000168254 ; CUAC ; • 2 ♂, 1 ♀; Anderson Co.; Clemson Experimental Forest, Big Oaks Area near Lake Hartwell ; 34.60225, - 82.83893; 21 May 2020; C. W. Harden and L. M. Thompson leg.; deep soil Berlese; CWHc ; • 1 ♂, 2 ♀; Anderson Co.; Clemson Experimental Forest, Big Oaks ; 34.61559, - 82.83061; 25 Mar 2020; C. W. Harden leg.; deep soil and litter Berlese; CWHc ; • 2 ♂; Oconee Co.; Lake Hartwell, Martin Creek Landing , SW of Clemson; 34.6389, - 82.8656; 4 Jan. 2020; C. W. Harden & L. M. Thompson leg.; soilwash flotation Berlese; CUAC 000168237 and CUAC 000168238 ; CWH- 070 and CWH- 114; CUAC ; • 1 ♂, 2 ♀; same data as previous; CWHc ; • 2 ♂; Oconee Co.; Lake Hartwell, Martin Creek Landing , SW of Clemson; 34.6389, - 82.8656; 4 Jan. 2020; C. W. Harden leg.; On underside of deeply embedded rocks; CUAC 000168243 and CUAC 000168233 ; CWH- 062 and CWH- 063; CUAC ; • 3 ♂; Oconee Co.; Lake Hartwell, Martin Creek Landing , SW of Clemson; 34.6389, - 82.8656; 31 Dec. 2019; C. W. Harden & L. M. Thompson leg.; On underside of deeply embedded rocks; CUAC 000168234 to CUAC 000168236 ; CWH- 064 to CWH- 066; CUAC ; • 1 ♂, 1 ♀; Oconee Co.; Lake Hartwell, Martin Creek Landing , SW of Clemson; 34.6389, - 82.8656; 11 Jan. 2020; C. W. Harden leg.; Under embedded rocks; CUAC 000168246 and CUAC 000168249 ; CWH- 119 and CWH- 123; CUAC ; • 1 larva; Oconee Co.; Martin Creek Landing ; 34.6388, - 82.8655; 15 May 2022; C. W. Harden and L. M. Thompson leg.; soilwashing; CWHc ; • 2 ♂, 6 ♀; Oconee Co.; Martin Creek Landing ; 34.6388, - 82.8644; 22 Oct 2021; C. W. Harden leg.; under rock; CWHc ; • 1 ♂, 2 ♀; Oconee Co.; Martin Creek Landing ; 34.6390, - 82.8638; 22 Oct 2021; C. W. Harden leg.; under rock; CWHc ; • 1 ♀; Oconee Co.; Martin Creek Landing ; 34.6391, - 82.8636; 22 Oct 2021; C. W. Harden leg.; under rock; CWHc ; • 1 ♀; Oconee Co.; Martin Creek Landing ; 34.6393, - 82.8633; 22 Oct 2021; C. W. Harden leg.; under rock; CWHc ; • 2 ♀; Oconee Co.; Lake Hartwell, Martin Creek Landing , southwest of Clemson; 34.6389, - 82.8656; 4 Jan 2020; C. W. Harden and L. M. Thompson leg.; CWHc ; • 1 ♂; Oconee Co.; Martin Creek Landing, southwest of Clemson ; 34.6389, - 82.8656; 13 Feb. 2023; C. W. Harden leg.; under rock; CWHc .

Diagnosis.

Males with metafemora not heavily modified, with a median tuberculate area on posterior margin (Fig. 12 D ), sometimes with a small blunt tooth. Male genitalia distinctive (Fig. 35 D – F ): median lobe of aedeagus with straight and narrow ventral margin, internal sac without groups of spines, flagellum relatively large and evenly curved.

Description.

Habitus Widely variable in body size (ABL = 1.46–1.78 mm, average = 1.63 ± 0.08) and shape, with smaller specimens being more convex and ovoid (Fig. 34 D ) and larger specimens being flatter and more parallel sided (similar to Fig. 34 E ). Males and females similarly variable in size (ABL = 1.51–1.78 mm and 1.46–1.78 mm, respectively). Not markedly narrow (average EW / ABL = 0.36). Integument Dorsal surface of head fully microsculptured; microsculpture coverage of pronotum varying: usually lacking from disc and present across entire anterior margin and along sides, sometimes absent anteriorly except for anterior angles; sometimes distinct across entire anterior 1 / 4, including part of disc. Head HW / PW = 0.74–79, antennomeres IV – X moniliform; frontoclypeal horn small, but distinct in lateral view; three pairs of supraorbital setae present, outer posterior pair smaller than other two. Pronotum Size and shape variable: PL / ABL = 0.22–0.24, PW / EW = 0.78–0.87, PbW / PW = 0.73–0.79. Sides either convergent or distinctly sinuate before posterior angles, which are either obtuse or nearly right. Elytra Variable in shape, either parallel sided and flat or slightly ovoid and convex. EL / ABL = 0.52–0.56. Legs Profemora of males unmodified. First protarsomere of males dilated and spinose on inner margin, bearing adhesive setae ventrally; second protarsomere of males unmodified. Mesotrochanters of males unmodified. Metafemora of males variable, either slightly enlarged medially with patch of coarse microsculpture (Fig. 12 D ) or swollen and bearing a blunt tooth on posterior margin. Females without leg modifications. Abdominal ventrites Unmodified in either sex. Male genitalia Aedeagus small (RL / ABL = 0.23). Median lobe (Fig. 35 F ) slightly rotated dorsally from plane of basal lobes, also curved towards left side in apical 1 / 2; slightly narrowed apically; ventral margin evenly curved, not expanded, without setae; dorsal margin sclerotized for ~ 2 / 3 its length; apex small, rounded. Internal sac covered in small scales, without spines; flagellum relatively long, not rotated dorsally, sinuate, abruptly narrowed apically, lightly sclerotized, and “ open ” laterally. Right paramere (Fig. 35 E ) small, broadly rounded, with four apical setae. Left paramere (Fig. 35 D ) subtriangular, ventral margin with four apical setae of variable length. Female genitalia Spermatheca long, abruptly expanded distally, stem with loose proximal coil, nearly straight before enlarged apex which is strongly curved (Fig. 21 K ). Spermathecal duct short, not coiled.

Distribution.

Endemic to South Carolina, known from Oconee and Anderson Counties on both sides of the former Seneca River (currently Lake Hartwell) from Seneca south to River Forks recreation area (Fig. 36 ).

Sympatry.

At the type locality, S. dunavani and a large Anillinus species belonging to the valentinei group ( Anillinus sp. “ South Carolina, Waldrop Stone ”) also occur. The other South Carolina members of the sinuaticollis group are apparently allopatric with respect to A. seneca .

Natural history.

Members of this species are endogean, inhabiting mineral soil layers in sandy clay rich soils. They have been collected beneath embedded rocks and through Berlese extraction of soil and washed soil. In samples from the type locality, Laboulbeniales fungi were observed on the dorsal surface of pronotum and elytra of several females and on the abdominal apex in a male. Specimens were collected in January, February, March, May, October, and December.

Species status justification.

The male genitalia are unique within the genus. DNA sequence data indicate that A. seneca is sister to the pair of A. mica and A. micamicus , both of which differ markedly in male genitalic characters.

Derivation of species name.

A noun in apposition, named for the former Seneca River. The known localities for this species are all near the former course of this river, which was lost due to the construction of Lake Hartwell in the 1950 s.

Notes.

DNA sequences of individuals from the opposite side of the historic course of the Seneca River in Anderson Co. are divergent from Oconee Co. individuals. There are no differences in genitalic morphology, and the divergence is interpreted as recent intraspecific variation. Still, those Anderson Co. individuals are not made part of the type series, in case future study concludes they are specifically distinct.

Anillinus sp. “ South Carolina, Coon Branch ”

Figs 21 G , 25 B , 36

Material examined (n = 3). USA • South Carolina • Oconee Co.; Coon Branch Natural Area ; • 1 ♂, 1 ♀; 35.020, - 83.000; 21 Jun. 2018; B. Owens and C. Carlton leg.; soil flotation; CUAC 000168231 and CUAC 000168232 , CWH- 102 and CWH- 178; CUAC • 1 ♂; 35.0256, - 83.0050; 2 Oct. 2021; C. W. Harden leg.; on soil under large rock.; CWHc.

GenBank: OR 853183, OR 839228, OR 839449, OR 837811, OR 837968, OR 838156, OR 839507, OR 837843, OR 837990, OR 838176.

Diagnosis. The male genitalia are similar to those of A. mica and A. micamicus , but differ in several characters: the shape of the median lobe is more elongate, with the ventral margin less curved and abruptly straightened at apex, which is obtusely angulate; the internal sac has a flagellum that is similar to A. micamicus , and has a single group of approximately 12 elongate, well-sclerotized spines on the left side; there is a sclerotized saddle like structure near the ostium, as in A. mica , but it is situated dorsal to the level of the flagellum; a pair of parallel rows of small sclerotized teeth run along the left side of the ostium, appearing as a pair of dark curved lines below the saddle like structure. The right paramere is encased in a membranous sheath as in A. mica and A. micamicus . The left paramere is shaped similar to that of A. micamicus , but the inner two setae on the apical margin are much shorter than the outer two, which are elongate but not as much as in A. mica and A. micamicus . The spermatheca (Fig. 21 G ) has a stem that is coiled evenly in a spiral; it is evenly enlarged distally. The duct has a single sharp bend just behind the junction with the spermatheca, and is otherwise straight and relatively wide, without coils. The bursa has a few lightly sclerotized regions.

Notes. The data from morphology and DNA sequences indicate that these individuals might represent a species distinct from A. micamicus . However, more sampling in the intervening area between Coon Branch and the localities of A. micamicus will be necessary to test this hypothesis.

‘ langdoni group’

Figures

Figure 12. SEM micrographs of male left metafemora of Anillinus species. Scale bar: 0.1 mm.

Figure 21. Spermathecae of Anillini species A, B Anillinus chandleri C Anillinus castaneus D Anillinus murrayae E Anillinus simplex F Anillinus dentatus G Anillinus sp. “ South Carolina, Coon Branch ” H Anillinus micamicus I Anillinus mica J Anillinus choestoea K Anillinus seneca L Anillinus montrex M Anillinus arenicollis N Anillinus jancae O Anillinus cf. nantahala P Anillinus cherokee Q Anillinus loweae R Anillinus merritti S Serranillus dunavani T Serranillus jeanneli. Scale bar: 0.1 mm.

Figure 24. Male ring sclerite, ventral aspect. A Anillinus chandleri B Anillinus castaneus C Anillinus sp. “ South Carolina, Chestnut Ridge ” D Anillinus murrayae E Anillinus simplex F Anillinus dentatus G Anillinus mica H Anillinus micamicus I Anillinus choestoea J Anillinus seneca K Anillinus arenicollis L Anillinus montrex M Anillinus jancae N Anillinus loweae O Anillinus cherokee P Anillinus merritti. Scale bar: 0.5 mm.

Figure 25. Anillini habitat in South Carolina A Waldrop Stone Falls, Pickens Co. (Anillinus mica, Anillinus micamicus, Anillinus murrayae, Serranillus dunavani) B Lower Whitewater River gorge, Oconee Co. (Anillinus cherokee, A. murrayae, Anillinus sp. “ South Carolina, Coon Branch ”, S. dunavani, Serranillus jeanneli, Serranillus sp. “ South Carolina, Coon Branch ” C Long Cane Creek, Abbeville Co. (Anillinus chandleri, Anillinus dentatus, Anillinus jancae, S. dunavani). The holotypes of A. mica and A. micamicus were collected under embedded rocks uphill of the wooden staircase in A. The holotype of A. jancae was collected in a pipe trap set on a hill just out of view in C.

Figure 34. Dorsal habitus of Anillinus species in the elongatus group and sinuaticollis group A Anillinus montrex B Anillinus arenicollis C Anillinus choestoea sp. nov. D Anillinus seneca sp. nov. E Anillinus mica sp. nov. F Anillinus micamicus sp. nov. Abdomens removed in B – F for DNA extraction. Scale bars: 1 mm.

Figure 35. Male genitalia of Anillinus species in the sinuaticollis group A – C Anillinus choestoea sp. nov. D – F Anillinus seneca sp. nov. G – I Anillinus mica sp. nov. J – L Anillinus micamicus sp. nov. Median lobe of aedeagus in right dorsolateral (C, I, L) or right lateral (F) aspect. Left parameres (A, D, G, J) and right parameres (B, E, H, K) in left and right lateral aspects, respectively. Scale bar: 0.1 mm.

Figure 36. Distribution map of sinuaticollis - group species of Anillinus in South Carolina. Data are from Harden (2024). Blue lines show modern and pre-inundation courses of the Tugaloo River and Seneca River and their major tributaries. The confluence of the two rivers becomes the Savannah River.