Anillinus relictus, Sokolov, 2021

Sokolov, Igor M., 2021, Two new species of the genus Anillinus Casey (Coleoptera, Carabidae, Anillini) from the southern United States, ZooKeys 1016, pp. 63-76 : 63

Anillinus relictus sp. nov. Figs 3 , 4A-C , 5

Type material.

Holotype, one male (CMNH), dissected, labeled: \ ALABAMA: Blount Co., Tidwell Hollow Nature Trail east of Oneonta. T. N. King April 1 1972 \ 4/1/72 o [handwritten] \ THOMAS C. BARR COLLECTION 2011 Acc. No. 38,014 \. Paratype, one female, labeled as holotype (CMNH).

Etymology.

The specific epithet is a Latin adjective, Anillinus relictus (from Latin: abandoned, forsaken), in the masculine form, and refers to the geographical isolation of this species from its morphologically closest congeners, as it is believed to be the only remaining eastern representative of an ancestral group once more widespread.

Type locality.

USA, Alabama, Blount County, the Oneonta area.

Recognition.

Adults of A. relictus can be distinguished from those of other members of eastern Anillinus by the combination of the large size, completely microsculptured head and pronotum, and, especially, by the long elytral vestiture equals to 0.5-0.7 of length of discal elytral setae.

Description.

Large-sized for genus (ABL 2.29-2.42 mm, mean 2.36 ± 0.092 mm, n = 2).

Habitus: Body form (Fig. 3A ) moderately convex, ovoid (WE/ABL 0.39 ± 0.012), head of average proportions for genus (WH/WPm 0.71 ± 0.023), pronotum moderately narrow in comparison to elytra (WPm/WE 0.77 ± 0.007).

Integument: Body color piceo-brunneus, appendages testaceous. Microsculpture (Fig. 3B-D ) present across all head, pronotum, and elytra, where it is represented by isodiametric polygonal sculpticells. Body surface shiny, surface sparsely and finely punctate, covered with moderately dense, yellowish, long setae. Vestiture of elytra (Fig. 3D ) long (0.5-0.7 length of discal setae). Elytral chaetotaxy typical for Anillinus , umbilicate series of type A (sensu Jeannel 1963a and Giachino and Vailati 2011).

Prothorax: Pronotum (Fig. 3C ) moderately convex, of moderate size (LP/LE 0.40 ± 0.003) and moderately transverse (WPm/LP 1.26 ± 0.028), with lateral margins almost rectilinearly and slightly constricted posteriorly (WPm/WPp 1.19 ± 0.013). Anterior angles slightly prominent, posterior angles nearly rectangular (95-100°). Width between posterior angles much greater than between anterior angles (WPa/WPp 0.87 ± 0.038). Basal margin slightly concave in middle.

Scutellum: Externally visible, triangular, with rounded apex.

Elytra: Narrowly depressed along suture, of average length (LE/ABL 0.59 ± 0.005) and width (WE/LE 0.66 ± 0.026) for genus, with traces of 6-7 striae. Humeri distinct, rounded, in outline forming obtuse angle with longitudinal axis of body. Lateral margins subparallel in middle, slightly convergent at basal fifth, evenly rounded to apex at apical fourth, with shallow subapical sinuation. Basal margination distinct.

Legs: Protarsi of male with moderately dilated tarsomere 1. Profemora moderately swollen. Metafemora unmodified.

Male genitalia: Median lobe of aedeagus (Fig. 4A ) anopic, slightly arcuate and slightly twisted. Basal orifice comparatively short for the genus. Shaft with long subparallel basal part, slightly dilating in apical third. Apical part with enlarged apex in form of rounded parallelogram. Dorsal margin slightly convex and strongly sclerotized at middle. Ventral margin curved near middle, where it is suddenly enlarged right before the apex. Endophallus with dorsal sclerite in form of a semicircular filament-like structure with short basal prolongations. Ventral sclerite located at apical orifice, in form of golf gap wedge plate. Dorsal scaly membranous field present at middle of dorsal sclerite. Enlarged apical area of median lobe with a dark spine-like structure (Fig. 4A , ss). Left paramere (Fig. 4B ) modified, with long, subparallel apical half of moderate width with one seta at angulate tip, basally with strong concave keel (bk), and thick basal processes of different length. Right paramere (Fig. 4C ) of moderate length, with eight setiferous pores bearing only three long setae (several others might be broken), which are shorter than length of paramere.

Female genitalia: Spermatheca not investigated. Ovipositor sclerites standard for genus with falciform gonocoxite 2 bearing two ensiform setae. Laterotergite with 8-9 setae.

Geographic distribution.

This species is known only from the type locality in Blount County, Alabama (Fig. 5 , red circle).

Habitat.

The label does not contain any habitat information. Presumably, this species is not a cavernicolous species.

Relationships.

Based on the structure of the median lobe, A. relictus is a sister species to the endogean A. sinuatus (Jeannel) ( Jeannel 1963a). The latter species is known to occur in Bexar County, Texas, where it was documented by a small series of three specimens extracted from the soil during surveys in peach orchards ( Jeannel 1963a; Sokolov et al. 2014). The range of A. sinuatus (Fig. 5 , black cross) is situated approximately 770 miles southwest of the type locality of A. relictus .

Figures

Figure 3. Digital images of external features of Anillinus relictus sp. nov. (male, E of Oneonta, Blount County, Alabama) A habitus, dorsal aspect B head, dorsal aspect C pronotum, dorsal aspect D elytral vestiture, left lateral aspect. Scale bars: 0.5 mm (A, D); 0.2 mm (B, C).

Figure 4. Digital images and line drawings of male genitalia of Anillinus species. A. relictus (E of Oneonta, Blount County, Alabama) A median lobe, right lateral aspect B left paramere, left lateral aspect C right paramere, right lateral aspect. A. sinuatus (Bexar County, Texas) D median lobe, right lateral aspect E left paramere, left lateral aspect F right paramere, right lateral aspect. bk - basal keel, dp - dorsal process, ss - spine-like structure, vs - ventral sclerite. Scale bars: 0.1 mm.

Figure 5. Map of the South of eastern United States, showing positions of locality records for the newly described species of Anillinus and the ranges of their presumed relatives (localities of the same color reflect supposed relatedness). A. felicianus, green circle; A. relictus, red circle. Green area with vertical line pattern - range of A. sinuaticollis. Black cross - type locality of A. sinuatus. Red areas with diagonal line pattern - ranges of the species of Anillinus whose males have a spine-like structure in the endophallus of the median lobe (after Sokolov et al. 2004; Sokolov and Watrous 2008; Sokolov 2011; Sokolov et al. 2014; Sokolov et al. 2017). Blue line - Mississippi River. State abbreviations follow Federal Information Processing Standards (https: // www. nlsinfo. org / content / cohorts / nlsy 79 / other-documentation / codebook-supplement / nlsy 79 - attachment- 102 - federal).