Orthobula calceata Simon, 1897

Haddad, Charles R., Jin, Chi & Platnick, Norman I., 2022, A revision of the spider genus Orthobula Simon, 1897 (Araneae: Trachelidae) in the Afrotropical Region. I. Continental species, Zootaxa 5133 (3), pp. 355-382 : 367-370

Orthobula calceata Simon, 1897

Figs 5, 6 , 65–75

Orthobula calceata Simon, 1897b: 499 (Holotype ♀: SIERRA LEONE: leg. Mocquerys, deposited in MNHN—examined). Orthobula calceata Ramírez, 2014: 212 , figs 140E, 165E–F, 180A.

Diagnosis. Females of O. calceata have a similar general epigyne structure to those of O. radiata , but can be distinguished by the curved anterolateral ridges flanking the CO and the very narrow separation of the ST I and SBB ( Fig. 65 ), with the ridges replaced by shallow depressions, and the ST I and SBB separated by approximately ½ SBB diameter, in O. radiata ( Figs 45 , 96 ). Males of O. calceata most closely resemble those of O. aethiopica sp. nov. in their palpal structure, particularly the slight undulation of the embolus in ventral view ( Figs 57 , 68 ), but can be distinguished by the shape of the RFA, which is short and hook-shaped in O. calceata ( Fig. 69 ) but longer and bifid in O. aethiopica sp. nov. ( Fig. 58 ).

Female (Badenou, ZFMK 8947). Measurements: CL 0.93, CW 0.71,AL 1.09,AW 0.99, TL 2.08 (1.60–2.25), PERW 0.29, MOQAW 0.13, MOQPW 0.17, MOQL 0.16. Length of leg segments: I 0.63 + 0.24 + 0.56 + 0.50 + 0.27 = 2.20; II 0.54 + 0.22 + 0.44 + 0.40 + 0.27 = 1.87; III 0.43 + 0.21 + 0.34 + 0.37 + 0.25 = 1.60; IV 0.60 + 0.22 + 0.53 + 0.59 + 0.29 = 2.23.

Colour: carapace bright yellow-orange, with black mottling around margins and sides, black mottled patch centrally; chelicerae yellow-brown; endites and labium yellow-brown, cream distally; sternum yellow-orange, with black mottled margins; palps yellow, tibiae with black mottling prolaterally and dorsally; legs with femora, patellae and tibiae orange-brown, with dense black mottling laterally; distal ends of anterior femora and tibiae, and proximal ends of patellae, with yellow rings; posterior femora, patellae and tibiae yellow, with pro- and retrolateral mottled markings in distal half of femora, only retrolaterally on patellae and tibiae; all metatarsi yellow, tarsi creamy-yellow; abdomen grey dorsally, with pair of longitudinal cream anterolateral patches and paired cream transverse patches at midpoint, merging in square medially; faint cream patch above spinnerets; venter cream, with small mottled grey patch in front of spinnerets; spinnerets cream.

Leg spination: femora and patellae: spineless; tibiae: I plv 6 rlv 5, II plv 4 rlv 4; metatarsi: I plv 4 rlv 4, II plv 4 rlv 4; tarsi: I plv 3 rlv 2, II plv 2 rlv 2.

Epigyne with lateral CO in curved anterolateral ridges ( Fig. 65 ); CO initially curving posteromesally, then bending sharply and diverging slightly before entering round SBB at centre of epigyne; SBB almost touching along their mesal surfaces, also almost touching anterior surface of ST I; CD approximately 1½ times width of SBB; BU ovoid, wrinkled, with finger-shaped accessory gland on their anteromesal surface; SBB connected to ST I by very short looping ducts, entering transversely oval ST I on their anteromesal surface ( Fig. 66 ).

Male (Bagoé River, ZFMK 8962). Measurements: CL 0.80, CW 0.63, AL 0.82, AW 0.61, TL 1.70 (1.30–1.70), PERW 0.28, MOQAW 0.11, MOQPW 0.15, MOQL 0.14. Length of leg segments: I 0.52 + 0.21 + 0.48 + 0.40 + 0.26 = 1.87; II 0.46 + 0.19 + 0.38 + 0.33 + 0.25 = 1.61; III 0.40 + 0.17 + 0.27 + 0.30 + 0.21 = 1.35; IV 0.51 + 0.25 + 0.44 + 0.46 + 0.27 = 1.93.

Colour: carapace yellow-orange with dense black mottling around margins and on sides, with distinct patch centrally; chelicerae yellow-orange; endites and labium yellow-orange, cream distally, proximal half of labium with black mottling; sternum yellow-orange, margins darker, with dense black mottling around margins; palps yellowbrown; legs yellow, anterior femora slightly darker; anterior femora with distal mottled patches laterally, patellae and tibiae with black mottling dorsally and laterally; posterior femora with distal mottled patch retrolaterally, extending as stripe along patellae and tibiae; abdomen black dorsally, with pair of cream oval anterolateral markings and transverse cream band at midpoint, latter expanded medially along anterior side; venter cream, epigastric plate with dense mottling laterally; lateral grey colouration extending as ring around spinnerets.

Leg spination: femora and patellae: spineless; tibiae: I plv 6 rlv 5, II plv 4 rlv 3; metatarsi: I plv 4 rlv 4, II plv 4 rlv 3; tarsi: I plv 3 rlv 3, II plv 3 rlv 2.

Palpal femur with small hook-shaped RFA ( Figs 67, 69 ); tibia with small, simple triangular apophysis; retrodistal tegular ridge weakly developed, only curving slightly to ventral surface, not close to base of embolus ( Fig. 68 ); embolus narrow, undulating slightly in ventral view, with weak curve at half its length ( Figs 67–69 ).

Other material examined. CAMEROON: Adamaoua : ca. 20 km S Minim, 06°49’N, 12°52’E, 1200 m a.s.l., III.1981, leg. W. Flacke & P. Nagel, 1♀ ( ZFMK 10429 ) ; Same locality, XI–XII.1980, leg. W. Flacke & P. Nagel, 1♂ ( ZFMK 10445 ) ; Tchabal Mbabo , SW slope, 07°25’N, 12°49’E, 1600 m a.s.l., 10.IV.1983, leg. R. Bosmans & Van Stalle (sweeping, transition between gallery forest and grassland), 1♂ ( MRAC 162251 ) . Northwest: Mount Oku , 06°15’N, 10°26’E, 8.III.1983, 2350 m a.s.l., leg. R. Bosmans & Van Stalle (pitfalls), 1♂ ( MRAC 162239 ) ; Ndop plateau, near Koutoupi, W slope, Massif de Mbam , 05°54’N, 10°44’E, 31.III.1983, 1100 m a.s.l., leg. R. Bosmans & Van Stalle (forest litter), 1♂ ( MRAC 162210 ) . COTE D’IVOIRE: Gôh-Djiboua: Gagnoa [06°08’N, 05°57’W], 26.VI.1996, leg. A. Russell-Smith (pitfall, upland rice), 1♂ 1♀ ( BMNH) . Lacs: Kossou , 06°57’N, 04°58’W, 24.XII.1974, leg. R. Jocqué (savanna), 1♂ ( MRAC 152488 ) . Savanes: Bagoé / Guingéréni , 09°32’N, 06°36’W, 14.II–13.III.1983, leg. Fliedner & Krüger, 3 imm. 4♂ 4♀ ( ZFMK 8945 ) ; Same locality, 14.II–13.III.1983, leg. Krüger & Summkeller (BF), 1 imm. 11♂ 4♀ ( ZFMK 8971 ) ; Same locality, 18.II–13.III.1983, leg. Krüger & Summkeller (BF/GW), 5♂ ( ZFMK 8972 ) ; Same locality, 21.II.1983, Krüger & Sumkeller (wasser bis 15:30), 1♂ ( ZFMK 8962 ) ; Same locality, III–IV.1984, leg. Krüger & Petermann (BF 1 GwD+P), 12♂ 2♀ ( ZFMK 8974 ) ; Same locality, 6–19.III.1984, leg. Krüger & Petermann, 1♂ ( ZFMK 8939 ) ; Same locality, 6–19.III.1984, leg. Krüger & Petermann (BF 6 Gw), 3♂ 2♀ ( ZFMK 8948 ) ; Near Korhogo , 09°27’N, 05°38’W, I.1980, leg. J. Everts (pitfalls, gallery forest), 1♂ 1♀ ( MRAC 169841 ) ; Same data but II.1980, 2♂ 1♀ ( MRAC 169.839 ) ; Same data but III.1980, 1♂ 1♀ ( MRAC 169840 ) ; Same data but V.1980, 3♀ ( MRAC 169843 ) ; Riv. Badeni / Tawara , 25 km N, 09°52’N, 05°39’W, 24.I–11.II.1983, leg. Krüger & Summkeller, 2 imm. 1♂ 1♀ ( ZFMK 8951 ) ; Riv. Badenou /M’bengué, 09°50’N, 05°50’W, 19.XI–9.XII.1984, leg. Krüger & Sumkeller (BF), 1♀ ( ZFMK 8987 ) ; Same locality, 7.XI–18.XII.1982, leg. Dister, Huschens & Sumkeller (FH), 4 imm. 3♂ 3♀ ( ZFMK 8959 ) ; Same locality, XI.1983, leg. R. Summkeller (oben), 1♂ 1♀ ( ZFMK 8947 ) ; Same locality, XII.1983, leg. R. Summkeller (hang quer), 2♂ ( ZFMK 8949 ) ; Same locality, XI–XII.1983, leg. G. Rosner & R. Summkeller, 1 imm. 1♀ ( ZFMK 8997 ) , 2♀ ( ZFMK 8961 ) . Sassandra-Marahoué: Bouaflé, Klébo , 06°52’N, 06°08’W, I.1981, leg. J. Everts (pitfall), 1♂ ( MRAC 166405 ) ; Same data but II.1981, 1♂ 1♀ ( MRAC 166385 ) . Vallée du Bandama: Bouaké [07°42’N, 05°02’W], 9.XI.1995, leg. A. Russell-Smith (rice, pitfalls, WARDA), 3♂ 5♀ ( BMNH) . Woroba: Touba [08°17’N, 07°41’W], 24.VIII.1995, leg. A. Russell-Smith (pitfall, rice), 1♂ ( BMNH) . D.R. CONGO: Équateur: Mabali, Bikoro District , 00°53’S, 18°07’E, X.1959, leg. N. Leleup, 1♀ ( MRAC 114565 ) . EQUATORIAL GUINEA: Kié-Ntem: Micomeseng , 02°08’N, 10°37’E, 13–17.VII.1989, leg. M. Alderweireldt (pitfall, field), 1♀ ( MRAC 170228 ) . GHANA: Greater Accra: Achimota [05°37’N, 00°13’W], V.1961, leg. C. Hinckley (on outside and in house), 1♀ ( MCZ 16418) . NIGERIA: Kwara: Borgu Game Reserve , 10°15’N, 04°10’E, 5–6.VIII.1973, leg. A. Russell-Smith (flood debris on river bank), 1♀ ( MRAC 160343 ) .

Habitat and biology. A common ground-dwelling spider sampled from pitfalls and litter in various forest and savanna habitats.

Distribution. Widespread in West Africa and the western parts of the Congo Basin ( Fig. 82 ); largely sympatric with O. marusiki sp. nov. ( Fig. 101 ) and often collected together in the same samples.

Variation. All of the examined O. calceata examined have some abdominal markings in both sexes, with the majority of specimens showing “complete” markings ( Figs 72, 75 ), and only a few individuals of each sex a reduction in their extent (e.g. Figs 70, 71, 73, 74 ).

Figures

FIGURE 82. Distribution of Orthobula aethiopica sp. nov. (circles), O. arca sp. nov. (squares) and O. calceata Simon, 1897 (triangles) in the continental Afrotropical Region.

FIGURE 101. Distribution of Orthobula marusiki sp. nov. (circles), O. milloti Caporiacco, 1949 (squares), O. radiata Simon, 1897 (triangles) and unidentified Orthobula species (red triangles) in the continental Afrotropical Region.

FIGURES 1–12. Dorsal habitus photographs of Orthobula species: 1. O. aethiopica sp. nov., female; 2. Same, male; 3. O. arca sp. nov., female; 4. Same, male; 5. O. calceata Simon, 1897, female; 6. Same, male; 7. O. marusiki sp. nov., female; 8. Same, male; 9. O. milloti Caporiacco, 1949, female; 10. Same, male; 11. O. radiata Simon, 1897, female; 12. Same, male. Scale bars: 1 mm.

FIGURES 65–69. Orthobula calceata Simon, 1897, genitalic morphology of female (65, 66) and male (67–69) from Bagoé: epigyne, ventral (65) and dorsal (66) views; palp, prolateral (67), ventral (68) and retrolateral (69) views. Scale bars: 0.10 mm.

FIGURES 70–81. Dorsal habitus photographs of Orthobula calceata Simon, 1897 females (70–72) and males (73–75) and O. marusiki sp. nov. females (76–78) and males (79–81), all from M’bengué, Cote d’Ivoire, indicating variation in extent of abdominal markings. Scale bars: 1 mm.

FIGURES 45–53. Scanning electron microscope photographs of Orthobula radiata Simon, 1897 female (45) and male (46–53): 45. Epigyne, ventral view; 46. Left palpal femur, retrolateral view; 47. Same, detail of ventrodistal apophysis; 48. Right palpal patella, tibia and tarsus, ventrolateral view; 49. Same, detail of patellar lyriform organ; 50. Same, detail of pores in lyriform organ; 51. Left palpal tibia, dorsolateral view; 52. Left embolus, retrolateral view; 53. Right embolus, retrolateral view, detail.

FIGURES 96–100. Orthobula radiata Simon, 1897, genitalic morphology of female (96, 97) and male (98–100) from Ndumo: epigyne, ventral (96) and dorsal (97) views; palp, prolateral (98), ventral (99) and retrolateral (100) views. Scale bars: 0.10 mm.

FIGURES 54–58. Orthobula aethiopica sp. nov., genitalic morphology of holotype female (54, 55) and paratype male (56–58) from Addis Ababa: epigyne, ventral (54) and dorsal (55) views; palp, prolateral (56), ventral (57) and retrolateral (58) views. Scale bars: 0.10 mm. Abbreviations: AG—accessory gland; BU—bursa; CD—copulatory duct; CO—copulatory opening; EM—embolus; FD—fertilisation duct; RFA—retrodistal femoral apophysis; RTA—retrolateral tibial apophysis; SBB—sclerotised base of bursa; ST I—primary spermathecae.