Geostiba

Gusarov, Vladimir I., 2002, A revision of Nearctic species of the genus Geostiba Thomson, 1858 (Coleoptera: Staphylinidae: Aleocharinae), Zootaxa 81, pp. 1-88 : 15-17

Key for Identification of Nearctic Species of Geostiba

1 In males pronotum with one medial tubercle at posterior margin; each elytron with a tubercle near scutellum but not at the elytral suture; abdominal tergum 7 with one short medial carina in front of posterior margin. Posterior margin of female sternum 8 distinctly convex, without medial emargination. Aedeagus: Figs. 1­3 in Assing (2001). Spermatheca: Fig. 4 in Assing (2001). Body length 2.3­2.8 mm, pronotal width 0.43­0.53 mm. Introduced from Europe to Newfoundland ( Fig. 336 ) ................ ......................................................................... 15. G. (s. str.) circellaris (Gravenhorst) .

– In males pronotum without a medial tubercle at posterior margin; elytral suture is raised behind scutellum (flat in G. impressula ); abdominal tergum 7 with two short and parallel medial carinae in front of posterior margin or without carinae. Posterior margin of female sternum 8 medially slightly concave or with emargination ( Figs. 32­ 33 , 54­55 ). Native Nearctic species ........................................................................... 2

2 Species occurring in eastern North America, east of the Rocky Mountains................. 3

– Species occurring in western North America, west of the Rocky Mountains ............ 15

3 Temples 2.3­2.7 times as long as eyes. Elytra (measured from humeral level) longer than pronotum. Wings fully developed. In males abdominal tergum 7 with two short and parallel medial carinae in front of posterior margin, abdominal tergum 8 with four short and weak carinae in front of posterior margin. Apex of median lobe in lateral view bent ventrally and widened apically ( Figs. 36­37 ). Body length 1.9­2.4 mm, pronotal width 0.40­0.47 mm. Widely distributed in eastern North America from Mount Rogers, Virginia in the south to Maine, Québec and Wisconsin in the north ( Fig. 337 )................................................ 1. G. (Sibiota) appalachigena Gusarov , sp. n.

– Temples 2.7­6.0 times as long as eyes. Elytra shorter than pronotum. Wings reduced to short vestiges, shorter than elytra. Apex of median lobe of aedeagus has different shape. Distributed in the Southern Appalachians (North Carolina and Tennessee) ( Figs. 337­338 ) ............................................................................................................ 4

4 Males (In males posterior margin of abdominal sternum 8 convex and without a fringe of wide setae ( Fig. 30 ) and some species with two medial carinae on tergum 7) ....... 5

– Females (In females posterior margin of abdominal sternum 8 medially emarginate or concave, with a fringe of wide setae ( Figs. 32­33 , 54­55 ). Females never have carinae on abdominal terga 7­8). Females can be reliably identified only by association with males or by comparing locality data with known geographical distribution of different species of Geostiba .

5 Abdominal tergum 7 with two short and parallel medial carinae in front of posterior margin, tergum 8 with four short and weak carinae in front of posterior margin ....... 6

– Abdominal terga 7 and 8 without carina or tubercles ................................................ 12

6 Body length 1.9­2.3 mm, pronotal width 0.40­0.46 mm. Antennal segment 4 slightly transverse (width to length ratio about 1.2; Fig. 16 ). Apex of median lobe in ventral view broad ( Figs. 57­58 , 77­78 ) .................................................................................. 7

– Body length 1.6­2.3 mm, pronotal width 0.34­0.43 mm. Antennal segment 4 strongly transverse (width to length ratio about 1.6; Fig. 17 ). Apex of median lobe in ventral view narrow ( Figs. 100­101 , 126­127 , 152­153 ) or broad (in G. balsamensis only, Figs. 193­194 ) ............................................................................................................. 8

7 Apex of median lobe of aedeagus in lateral view not bent ventrally ( Figs. 59­60 ). Body length 2.0­ 2.3 mm, pronotal width 0.40­0.46 mm. Known from the Great Balsam Mountains and Little Pisgah Mountain in the Southern Appalachians( Figs. 338 , 340 ) ...................................................................2. G. (Sibiota) bicarinata Lohse & Smetana

– Median lobe of aedeagus in lateral view bent ventrally ( Figs. 79­80 ). Body length 1.9­ 2.3 mm, pronotal width 0.41­0.44 mm. Known from Graveyard Ridge and Black Balsam Knob in the Great Balsam Mountains – Pisgah Ridge massif in the Southern Appalachians ( Figs. 338 , 340 ) .............................. 3. G. (Sibiota) graveyardensis Pace

8 Apex of median lobe in ventral view broad ( Figs. 193­194 ). Medial carinae on male tergum 7 weak. Body length 1.8­2.2 mm, pronotal width 0.36­0.39 mm. Known from the Plott Balsams – Cataloochee Divide massif in the Southern Appalachians ( Figs. 338 , 340 ) ................................................................... 8. G. (Sibiota) balsamensis Pace

– Apex of median lobe in ventral view narrow ( Figs. 100­101 , 126­127 , 152­153 ). Medial carinae on male tergum 7 strong ..................................................................... 9

9 Apex of median lobe in lateral view with obtuse ventral projection ( Figs. 176­177 ). Body length 1.8­2.3 mm, pronotal width 0.34­0.40 mm. Known from Snake Den Mountain in the Great Smoky Mountains massif ( Figs. 338 , 340 ) ................................................................................................7. G. (Sibiota) crepusculigena Gusarov , sp. n.

– Apex of median lobe in lateral view without obtuse ventral projection ( Figs. 102­103 , 128­129 , 155­156 ) ..................................................................................................... 10

10 Apex of median lobe longer ( Figs. 100­107 ), in ventral view the apex outline convex apically ( Figs. 101, 105 ), in lateral view without denticle ( Figs. 103, 107 ). Body length 1.6­2.0 mm, pronotal width 0.37­0.40 mm. Known from many localities in the Great Smoky Mountains massif ( Figs. 338 , 340 ) ..............................................................................................................................4. G. (Sibiota) nimbicola Lohse & Smetana

– Apex of median lobe shorter ( Figs. 126­133 , 152­156 ), in ventral view the apex outline often doubly emarginate ( Figs. 131 , 153­154 ), in lateral view with a denticle ( Figs. 128­129 , 155­156 ) ........................................................................................... 11

11 Apex of median lobe in lateral view with a strong ventral denticle ( Figs. 155­156 ), in ventral view the apex outline strongly doubly emarginate ( Figs. 152­154 ). Body

length 1.6­1.9 mm, pronotal width 0.37­0.40 mm. Known from many localities in the Great Smoky Mountains massif ( Figs. 338 , 340 ) .......................................................... ...................................................................... 6. G. (Sibiota) nebuligena Gusarov , sp. n. – Apex of median lobe in lateral view with a weak ventral denticle ( Figs. 128­129 ), in ventral view the apex outline weakly doubly emarginate ( Figs. 130­131 ) or convex ( Figs. 126­127, 132­133 ). Body length 1.9­2.2 mm, pronotal width 0.36­0.43 mm. Known from the Plott Balsams – Cataloochee Divide massif in the Southern Appalachians ( Figs. 338 , 340 ) .................................. 5. G. (Sibiota) pluvigena Gusarov , sp. n.

12 Body length 1.8­2.2 mm, pronotal width 0.34­0.39 mm. Lateral sides of the apex of median lobe with shallow emargination (in ventral view) ( Figs. 219­220, 223­229 , 249­250 ) ..................................................................................................................... 13

– Body length 1.9­2.6 mm, pronotal width 0.39­0.44 mm. Lateral sides of the apex of median lobe with deep emargination (in ventral view) ( Figs. 267­268 , 289­291 ) ..... 14

13 Median lobe of aedeagus in ventral view more narrow ( Figs. 219­220, 223­229 ). Distal diverticula of internal sac long ( Figs. 233­234 ), proximal diverticula small ( Fig. 234 ). Body length 1.8­2.2 mm, pronotal width 0.34­0.39 mm. Known from the Great Balsam Mountains – Pisgah Ridge massif and from Standing Indian in the Blue Ridge in the Southern Appalachians ( Figs. 338 , 340 ) .............................................................. .................................................................... 9. G. (Sibiota) nubigena Lohse & Smetana

– Median lobe of aedeagus in ventral view wider ( Figs. 249­250 ). Distal diverticula of internal sac short and small ( Figs. 253, 256 ), proximal diverticula very large ( Figs. 253, 257­258 ). Body length 1.8­1.9 mm, pronotal width 0.34 mm. Known only from the Great Smoky Mountains west of Clingmans Dome ( Figs. 338 , 340 ) ...................... ..................................................................... 10. G. (Sibiota) coeligena Gusarov , sp. n.

14 Median lobe of aedeagus longer ( Fig. 269 ), in lateral view more narrow ( Figs. 269­ 270 ), in ventral view the lateral sides of the apex less convex ( Figs. 267­268 ). Body length 1.9­2.4 mm, pronotal width 0.39­0.44 mm. Known only from the Great Craggy Mountains and the Black Mountains in the Southern Appalachians ( Figs. 338­339 ) .... ..................................................................... 11. G. (Sibiota) alticola Lohse & Smetana

– Median lobe of aedeagus shorter ( Fig. 292 ), in lateral view broader ( Figs. 292­293 ), in ventral view the lateral sides of the apex more convex ( Figs. 289­291 ). Body length 2.2­2.6 mm, pronotal width 0.40­0.44 mm. Known only from Roan Mountain and the Big Bald (Bald Mountains) in the Southern Appalachians ( Figs. 338­339 ) .................. ................................................................................... 12. G. (Sibiota) carteriensis Pace

15 Elytra (measured from humeral level) shorter than pronotum. Wings reduced, shorter than elytra. In males pronotum with strong, wide and deep impression along midline. Median lobe of aedeagus with wider apex (in ventral view) ( Figs. 310­312, 315 ). Body length 2.2­2.7 mm, pronotal width 0.37­0.50 mm. Known from Oregon ( Fig. 336 ) ................................................................................ 13. G. (Sibiota) impressula (Casey)

– Elytra as long as pronotum. Wings fully developed. In males pronotum without deep impression along midline. Median lobe of aedeagus with more narrow apex (in ventral view ( Figs. 323­324 ). Body length 2.4 mm, pronotal width 0.41 mm. Known from California ( Fig. 336 )............................ 14. G. (Sibiota) silvigena Gusarov , sp. n.

Figures

FIGURE 336. Geographical distribution of Nearctic species of Geostiba. The ellipse indicates the area where eleven Southern Appalachian species are distributed.

FIGURE 337. Geographical distribution of Geostiba appalachigena Gusarov, sp. n. The ellipse indicates the area where eleven Southern Appalachian species are distributed.

FIGURE 338. Geographical distribution of twelve species of Geostiba in the Southern Appalachians. Isohypses 1200 m and 1500 m are shown. Areas above 1500 m are solid black.

FIGURE 340. Detailed geographical distribution of Geostiba bicarinata Lohse & Smetana (2), G. graveyardensis Pace (3), G. nimbicola Lohse & Smetana (4), G. pluvigena Gusarov, sp. n. (5), G. nebuligena Gusarov, sp. n. (6), G. crepusculigena Gusarov, sp. n. (7), G. balsamensis Pace (8), G. nubigena Lohse & Smetana (9), G. coeligena Gusarov, sp. n. (10) in the Southern Appalachians. Isohypses 1200 m and 1500 m are shown. Areas above 1500 m are solid black.

FIGURES 1 ­ 7. Mouthparts of Geostiba circellaris (Gravenhorst) (1 ­ 2, Moscow Region, Russia), G. carteriensis Pace (3 ­ 4, Tennessee), G. appalachigena Gusarov, sp. n. (5 ­ 6, paratype from West Virginia) and G. pluvigena Gusarov, sp. n. (7, paratype from North Carolina). 1, 3 – labrum; 2, 4 – epipharynx; 5 – left mandible, dorsal view; 6 – left mandible, ventral view; 7 – right mandible, dorsal view. Scale bar 0.1 mm.

FIGURES 29 ­ 33. Abdominal segment 8 of Geostiba appalachigena Gusarov, sp. n. (paratypes from Black Mountain, West Virginia). 29 – male tergum 8; 30 – male sternum 8; 31 – female tergum 8; 32 – female sternum 8, 33 – apex of female sternum 8. Scale bar 0.2 mm (29 ­ 32), 0.1 mm (33).

FIGURES 51 ­ 56. Abdominal segments 7 ­ 8 of Geostiba bicarinata Lohse & Smetana (Richland Balsam Mountain, North Carolina). 51 – male tergum 8; 52 – male sternum 8; 53 – female tergum 8; 54 – female sternum 8, 55 – apex of female sternum 8; 56 – medial portion of male tergum 7, posterior down. Scale bar 0.2 mm (51 ­ 54, 56), 0.1 mm (55).

FIGURES 34 ­ 37. Aedeagus of Geostiba appalachigena Gusarov, sp. n. (paratype from Black Mountain, West Virginia). 34 – median lobe, ventral view; 35 – apex of median lobe, ventral view; 36 – median lobe, lateral view; 37 – apex of median lobe, lateral view. Scale bar 0.2 mm (34, 36), 0.1 mm (35, 37).

FIGURES 8 ­ 17. Mouthparts of Geostiba circellaris (Gravenhorst) (8, Moscow Region, Russia), G. infirma (Weise) (9, Ivano­Frankovsk Region, Ukraine), G. carteriensis Pace (10 ­ 15, Tennessee), G. appalachigena Gusarov, sp. n. (16, paratype from West Virginia) and G. pluvigena Gusarov, sp. n. (17, paratype from North Carolina). 8 ­ 10, – prementum; 11 – hypopharynx; 12 – left maxilla, ventral view; 13 – left galea, dorsal view; 14 – left lacinia, dorsal view; 15 – mentum; 16 ­ 17 – right antenna. Scale bar 0.1 mm (8 ­ 15), 0.2 mm (16 ­ 17). L – Length of antennal article.

FIGURES 57 ­ 60. Aedeagus of Geostiba bicarinata Lohse & Smetana (Richland Balsam Mountain, North Carolina). 57 – median lobe, ventral view; 58 – apex of median lobe, ventral view; 59 – median lobe, lateral view; 60 – apex of median lobe, lateral view. Scale bar 0.2 mm (57, 59), 0.1 mm (58, 60).

FIGURES 77 ­ 80. Aedeagus of Geostiba graveyardensis Pace (Graveyard Fields, North Carolina). 77 – median lobe, ventral view; 78 – apex of median lobe, ventral view; 79 – median lobe, lateral view; 80 – apex of median lobe, lateral view. Scale bar 0.2 mm (77, 79), 0.1 mm (78, 80).

FIGURES 100 ­ 107. Aedeagus of Geostiba nimbicola Lohse & Smetana (100 ­ 103 – holotype; 104 ­ 107 – Mount Sterling Ridge Trail, Tennessee). 100, 104 – median lobe, ventral view; 101, 105 – apex of median lobe, ventral view; 102, 106 – median lobe, lateral view; 103, 107 – apex of median lobe, lateral view. Scale bar 0.2 mm (100, 102, 104, 106), 0.1 mm (101, 103, 105, 107).

FIGURES 126 ­ 133. Aedeagus of Geostiba pluvigena Gusarov, sp. n. (paratypes from the junction of Blue Ridge Parkway and Balsam Mountain Road (126 ­ 129, 132 ­ 133) and Waterrock Knob (130 ­ 131), North Carolina). 126, 130, 132 – median lobe, ventral view; 127, 131, 133 – apex of median lobe, ventral view; 128 – median lobe, lateral view; 129 – apex of median lobe, lateral view. Scale bar 0.2 mm (126, 128, 130, 132), 0.1 mm (127, 129, 131, 133).

FIGURES 152 ­ 156. Aedeagus of Geostiba nebuligena Gusarov, sp. n. (paratypes from Highways 441 & 71, Tennessee (152, 154 ­ 156) and Appalachian National Scenic Trail W of Clingmans Dome (153), Tennessee / North Carolina). 152 – median lobe, ventral view; 153 ­ 154 – apex of median lobe, ventral view; 155 – median lobe, lateral view; 156 – apex of median lobe, lateral view. Scale bar 0.2 mm (152, 155), 0.1 mm (153 ­ 154, 156).

FIGURES 193 ­ 196. Aedeagus of Geostiba balsamensis Pace (Cataloochee Balsam Mountain, North Carolina). 193 – median lobe, ventral view; 194 – apex of median lobe, ventral view; 195 – median lobe, lateral view; 196 – apex of median lobe, lateral view. Scale bar 0.2 mm (193, 195), 0.1 mm (194, 196).

FIGURES 174 ­ 177. Aedeagus of Geostiba crepusculigena Gusarov, sp. n. (paratype from Snake Ridge Trail, Tennessee). 174 – median lobe, ventral view; 175 – apex of median lobe, ventral view; 176 – median lobe, lateral view; 177 – apex of median lobe, lateral view. Scale bar 0.2 mm (174, 176), 0.1 mm (175, 177).

FIGURES 219 ­ 229. Aedeagus of Geostiba nubigena Lohse & Smetana (Richland Balsam Mountain (219 ­ 222), Blue Ridge Parkway (223), Graveyard Fields (224 ­ 227) and Grassy Ridge Mine Overlook (228 ­ 229), North Carolina). 219, 224, 226, 228 – median lobe, ventral view; 220, 223, 225, 227, 229 – apex of median lobe, ventral view; 221 – median lobe, lateral view; 222 – apex of median lobe, lateral view. Scale bar 0.2 mm (219, 221, 224, 226, 228), 0.1 mm (220, 222 ­ 223, 225, 227, 229).

FIGURES 247 ­ 252. Abdominal segment 8 and aedeagus of Geostiba coeligena Gusarov, sp. n. (paratype). 247 – male tergum 8; 248 – male sternum 8; 249 – median lobe, ventral view; 250 – apex of median lobe, ventral view; 251 – median lobe, lateral view; 252 – apex of median lobe, lateral view. Scale bar 0.2 mm (247 ­ 249, 251), 0.1 mm (250, 252).

FIGURES 267 ­ 270. Aedeagus of Geostiba alticola Lohse & Smetana (N slope of Mt. Mitchell, North Carolina). 267 – median lobe, ventral view; 268 – apex of median lobe, ventral view; 269 – median lobe, lateral view; 270 – apex of median lobe, lateral view. Scale bar 0.2 mm (267, 269), 0.1 mm (268, 270).

FIGURES 289 ­ 293. Aedeagus of Geostiba carteriensis Pace (Big Bald (289) and Roan Road Pass (290 ­ 293), Tennessee / North Carolina). 289 ­ 290 – median lobe, ventral view; 291 – apex of median lobe, ventral view; 292 – median lobe, lateral view; 293 – apex of median lobe, lateral view. Scale bar 0.2 mm (289 ­ 290, 292), 0.1 mm (291, 293).

FIGURES 230 ­ 246. Genitalia of Geostiba nubigena Lohse & Smetana (Richland Balsam Mountain (230 ­ 231, 234 ­ 235, 237 ­ 238, 242, 246) and Blue Ridge Parkway (232 ­ 233, 236, 239 ­ 241, 243 ­ 245), North Carolina). 230 – details of internal sac retracted into median lobe, ventral view; 231 – copulatory piece of internal sac, dorsal view; 232 – medial lamellae of internal sac, ventral view; 233 – distal diverticula of everted internal sac, ventral view; 234 – everted internal sac, ventral view; 235 ­ 236 – spermatheca; 237 ­ 238 – details of internal sac retracted into median lobe, lateral view; 239 – partially everted internal sac, lateral view; 240 – details of internal sac inside partially everted internal sac, lateral view; 241 – everted internal sac, lateral view; 242 – completely everted internal sac, lateral view; 243 – copulatory piece of internal sac, lateral view; 244 – medial lamella of internal sac, lateral view; 245 – right distal diverticulum of everted internal sac, lateral view; 246 – apex of left paramere, side facing median lobe. Scale bar 0.2 mm (230, 234, 237 ­ 242), 0.1 mm (231 ­ 233, 235 ­ 236, 243 ­ 246).

FIGURES 253 ­ 261. Aedeagus of Geostiba coeligena Gusarov, sp. n. (253, 256 ­ 258, 260 ­ 261 – paratype, 254 ­ 255, 259 ­ holotype). 253 – everted internal sac, ventral view; 254 – copulatory piece of internal sac, dorsal view; 255 – medial lamellae of internal sac, ventral view; 256 – distal diverticula of everted internal sac, ventral view; 257 – left proximal diverticulum of everted internal sac, ventral view; 258 – everted internal sac, lateral view; 259 – copulatory piece of internal sac, lateral view; 260 – medial lamella of internal sac, lateral view; 261 – apex of left paramere, side facing median lobe. Scale bar 0.2 mm (253, 258), 0.1 mm (254 ­ 257, 259 ­ 261).

FIGURES 310 ­ 315. Aedeagus of Geostiba impressula (Casey) (lectotype of Sipalia fossata Casey (310 ­ 311) and a specimen from Triangle Lake, Oregon (312 ­ 315 )). 310, 312 – median lobe, ventral view; 311, 315 – apex of median lobe, ventral view; 313 – median lobe, lateral view; 314 – apex of median lobe, lateral view. Scale bar 0.4 mm (310, 312 ­ 313), 0.2 mm (311, 314 ­ 315).

FIGURES 321 ­ 326. Abdominal segment 8 and aedeagus of Geostiba silvigena Gusarov, sp. n. (holotype). 321 – male tergum 8; 322 – male sternum 8; 323 – median lobe, ventral view; 324 – apex of median lobe, ventral view; 325 – median lobe, lateral view; 326 – apex of median lobe, lateral view. Scale bar 0.4 mm (321 ­ 323, 325), 0.2 mm (324, 326).