Rhexius (Rhexius) jaceus Owens and Carlton, 2016

Owens, Brittany E. & Carlton, Christopher E., 2016, Collecting in the Museum: New Species, Taxonomic Changes, and Range Extensions of Euplectite Pselaphinae (Coleoptera: Staphylinidae) of the Southeastern United States, The Coleopterists Bulletin 70 (3), pp. 611-633 : 611-633

Rhexius (Rhexius) jaceus Owens and Carlton , new species

( Fig. 14 )

Type Material. Holotype, male: Tennessee: Blount Co. GSMNP, Rich Mt. Gap at 35°38.73N 83°48.33W 595m Forest litter. 30 July 2004. R. T. Allen RTA-04-91. ( FMNH) . Paratype, one male: Tennessee: Blount Co. GSMNP, Rich Mt. Gap at 35°38.73N 83°48.33W 595m Forest litter. 30 July 2004. R. T . Allen RTA-04-91. ( LSAM).

Etymology. The specific epithet refers to the father of the first author, who has provided a lifetime of enthusiastic support and encouragement that has made this study possible.

Diagnosis. This species is distinguished externally from R. substriatus , R. stephani , and R. ferrugineus , by the presence of a wide laterobasal impression on ventrite III (at least two times as wide as the non-impressed area at the apex of ventrite III). Additionally, the aedeagus is unique ( Fig. 14 ), with a flattened, broad ventral lobe and a median lobe bearing three distal extensions and an acute dorsal process ( Fig. 14 ).

Description. Male. Measurements: HL = 0.20 mm, HW = 0.35 mm; PL = 0.30 mm, PW = 0.35 mm; EL = 0.48 mm, EW = 0.58 mm; A1–6, respectively, = 0.10, 0.18, 0.11, 0.10, 0.12, 0.4 mm; An1–11, respectively, = 0.14, 0.05, 0.02, 0.02, 0.02, 0.02, 0.02, 0.02, 0.03, 0.02, 0.11 mm; MP1–4, respectively, = 0.01, 0.02, 0.01, 0.05 mm; GL = 0.41 mm, GW = 0.25 mm; ML = 2.2 mm. Integument: Head, pronotum, elytra, and abdomen dark brown, appendages light brown. Entire surface covered with semierect pubescence. Pubescence in gular area longer and denser than on other parts of body, some setae capitate. Abdomen: Ventrite III with basolateral impressions, each impression with vertical shelf at base extending ventrally to apex of ventrite II. Penial plate rounded-ovate. Other ventrites unmodified. Genitalia: Aedeagus asymmetrical. Ventral lobe flattened with patch of distal setae, bearing a semi-circular lamina folded in on right side. Median lobe straight and expanded distally into 3 separate processes with middle process bearing patch of setae apically. Basal bulb rounded, dorsal diaphragm obvious.

Female. Unknown.

Distribution. This species is known only from the type locality: Tennessee: Blount Co.

CHECKLIST OF THE SOUTHEASTERN NORTH

AMERICAN SPECIES OF RHEXIUS LECONTE

(Modified from Chandler 1997)

Rhexius LeConte, 1849: 102 (as genus).

TYPE SPECIES: Rhexius insculptus LeConte (monotypic) .

REVISION and KEY: Casey 1908; Chandler 1990: 506–510.

REDESCRIPTION: Grigarick and Schuster 1980: 21, plate 18, figs. 1–7, plate 75, fig. 3, plate 77, fig. 1.

Subgenus Rhexius LeConte, 1849 .

Rhexius amyae Owens and Carlton , new species.

TYPE DEPOSITORY: FMNH .

DISTRIBUTION: TN: Blount Co., Sevier Co., Swain Co., Great Smoky Mountains National Park; TN.

HABITAT: Forest litter.

Rhexius ferrugineus Casey, 1908 .

Rhexius ferrugineus Casey 1908: 280 .

TYPE DEPOSITORY: USNM .

Rhexius ruber Casey 1908: 279 ; Chandler 1990: 508 (synon. R. ferrugineus ).

TYPE DEPOSITORY: USNM .

Rhexius transversus Casey 1908: 281 ; Chandler 1990: 508 (synon. R. ferrugineus ).

TYPE DEPOSTORY: USNM .

REDESCRIPTION: Chandler 1990: 508, figs. 3–4.

DISTRIBUTION: AL, DC, FL, GA, IN, MD, MS, NC, OH, OK, LA, PA, VA.

HABITAT: Litter (cypress marsh edge), grass roots.

Rhexius insculptus LeConte, 1849 .

Rhexius insculptus LeConte, 1849: 103 .

TYPE DEPOSITORY: MCZC .

REDESCRIPTION: Casey 1908; Chandler 1990: 508–509, fig. 5.

DISTRIBUTION: LA: Orleans Parish; FL, GA, IL, LA, MO, MS, OH, OK.

BIOLOGY: Park et al. 1949, 1953; Reichle 1969.

HABITAT: Leaf litter (hardwood), sphagnum moss, rotten wood, flood debris.

Rhexius jaceus Owens and Carlton , new species.

TYPE DEPOSITORY: FMNH .

DISTRIBUTION: TN: Blount Co., Great Smoky Mountains National Park; TN.

HABITAT: Forest litter.

Rhexius ouachita Chandler, 1990 .

Rhexius ouachita Chandler 1990: 510 , fig. 8.

TYPE DEPOSITORY: FMNH .

DISTRIBUTION: OK, AR.

HABITAT: Forest litter, flood debris.

Rhexius schmitti Brendel, 1893 .

Rhexius schmitti Brendel 1893: 281 , pl. IV, fig. 20.

TYPE DEPOSITORY: ANSP .

Rhexius hirsutus Casey 1908: 279 ; Chandler 1990: 510, fig. 8 (synon. R. schmitti ).

TYPE DEPOSITORY: USNM .

REDESCRIPTION: Casey 1908; Chandler 1990: 510, fig. 8.

DISTRIBUTION: AL, AR, FL, GA, IN, KY, MD, MO, MS, NC, OH, OK, PA, VA, WV.

HABITAT: Leaf litter, rotten wood.

Rhexius stephani Chandler, 1990 .

Rhexius stephani Chandler 1990: 507–508 , fig. 2.

TYPE DEPOSITORY: FMNH .

DISTRIBUTION: OK: Latimer Co.; IL, OK, TX.

HABITAT: Grass roots, flood debris.

Rhexius substriatus LeConte, 1878 .

Rhexius substriatus LeConte, 1878: 383 .

TYPE DEPOSITORY: MCZC .

Rhexius virginicus Casey 1908: 280 ; Chandler 1990: 507, fig.1 (synonymy with R.substriatus ).

TYPE DEPOSITORY: USNM .

DISTRIBUTION: FL: Hillsborough Co.; VA: Norfolk; AL, FL, MD, MS, NC, VA.

HABITAT: Leaf litter (sand pine, oak, mixed hardwood).

Figures

Figs. 13–15. 13) Rhexius amyae - a) Habitus, dorsal view, b) Habitus, lateral view, c) Aedeagus, dorsal view;