Ebo Keyserling, 1884

Muster, Christoph, 2009, The Ebo-like running crab spiders in the Old World (Araneae, Philodromidae), ZooKeys 16 (16), pp. 47-73 : 51-53

Genus Ebo Keyserling, 1884

Ebo Keyserling, 1884: 678 . – Simon 1895: 1063; Schick 1965: 84 (subgenus Ebo ); Sauer and Platnick 1972: 36-37 (subgenus Ebo ); Dondale and Redner 1978: 29-30 (ad part.).

Type species. Ebo latithorax Keyserling, 1884 by monotypy

Material examined. Ebo evansae Sauer & Platnick, 1972 : USA: Utah: 4♁, 4♀, Salt Lake City, dry canyon, 40° 46’N, 111° 50’W, 11 March 1944, leg. W. Ivie (AMNH).

Ebo latithorax : USA: Pennsylvania: 2♁, Rector , 40° 12’N, 79° 14’W, 20 June 1967, leg. B. Vogel (AMNH). Ebo cf. latithorax : USA: Kansas: 1♁, 5♀, Ellsworth , 38° 34’N, 98° 14’W, 23 August 1935, leg. W. Ivie (AMNH). Ebo pepinensis Gertsch, 1933 : USA: Utah: 3♁, 3♀, west side of Utah Lake , 40° 16’N, 111° 56’W, 11 March 1934, leg. W. Ivie (AMNH) .

Diagnosis. Philodromid spiders with enlarged AME (AME size index 0.067-0.08) and extremely elongated leg II (Leg II length index 1.5-2.2). Prosoma wider than long ( Fig. 11 ). Clypeus low (Clypeus height index <0.1, Fig. 7 ). Leg formula 2143. Spination of legs generally reduced with species-specific modifications (males of E. latithorax are completely spineless), tibiae and metatarsi always without pro- and retrolateral spines. Metatarsus III and IV ventral 2-2-2 (except E. latithorax ). Patella of male palp without apophysis, tibia with indistinct VTA (sometimes completely reduced) and small, weakly sclerotized RTA. Embolus curved, its tip flexible, pointing to retrolateral side ( Fig. 2 ). Tegulum without apophysis. Conductor a retrolateral shallow groove. Epigyne weakly sclerotized, without atrium or grooves, epigynal suture entirely shifted to epigastric furrow. Glandular heads separated from receptacula, connected by thin ducts.

Remarks. The Nearctic Ebo species were thoroughly revised by Schick (1965) and Sauer and Platnick (1972). In both these studies Titanebo described by Gertsch (1933) was regarded a subgenus of Ebo . All Nearctic species indeed share a number of characters, e.g. the lack of PTA, the curved embolus with a flexible tip and the constitution of the conductor. However, the leg spination pattern is strikingly different, with Titanebo resembling Rhysodromus (the Philodromus histrio group) and Halodromus gen. n. Ebo and Titanebo are also different in the structure of the female genitalia and in some morphometric indices ( Table 1 ). In none of the phylogenetic analyses performed by Muster (2009) did Titanebo emerge as sister to Ebo . In conclusion, Titanebo clearly deserves generic re-establishment.

Composition and distribution. The centre of diversity is undoubtly North America. Sauer and Platnick (1972) included seven Nearctic species in the subgenus Ebo : E. contrastus Sauer & Platnick, 1972 , E. evansae Sauer & Platnick, 1972 , E. iviei Sauer & Platnick, 1972 , E. lathithorax Keyserling, 1884 , E. merkeli Schick, 1965 , E. pepinensis Gertsch, 1933 , and E. punctatus Sauer & Platnick, 1972 . Two further species were added by Platnick (1972) and Cokendolpher (1978), E. bucklei Platnick, 1972 , and E. redneri Cokendolpher, 1978 . Old World species described in Ebo are either transferred to Halodromus gen. n. or Philodromus , or they are regarded together with three Neotropical species as incertae sedis.

Figures

Figures 7-16. 7, 11 Ebo pepinensis from Utah Lake 8, 12 Titanebo parabolis from Utah 9, 15 Halodromus patellaris, from Monastir 10 Philodromus lepidus from Kebili, Tunisia 13 Halodromus patellidens from Kuwait 14 Halodromus barbarae sp. n. from Cartagena 16 Halodromus gershomi sp. n. from Massawa 7-10 Female clypeus and chelicerae, frontal view 11-16 Female cephalothorax, dorsal view. Scale lines = 0.5 mm.

Figures 1-6. 1, 4 Halodromus patellaris from Monastir 2 Ebo pepinensis from Utah Lake 3 Titanebo albocaudatus from Abilene 5-6 Titanebo andreaannae from Tucson 1-3 Left male palp, ventral view 4 Tarsal claws and scopulae 5 Epigyne, dorsal view, showing schematic course of the internal ducts (broken black line) and the demarcation between bursa copulatrix and copulatory ducts (white line) 6 Details of receptacula, showing numerous pores in the torus region.

Tables

Table 1. Morphometric indices in Ebo-like philodromid genera. Leg II length index = length femur II/femur I; AME size index = diameter AME/CW; PME interdistance index = PME-PME/PME-PLE; clypeus height index = ClyH/CW.

	Ebo	Titanebo	Halodromus	Philodromus histrio group
males
leg II length index	1.6 - 2.1	1.5 - 1.7	1.4 - 1.5	1.1 - 1.4
AME size index	0.071 - 0.077	0.054 - 0.076	0.063 - 0.084	0.035 - 0.058
PME interdistance index	1.88 - 2.11	1.80 - 2.07	1.56 - 2.00	1.63 - 3.00
clypeus height index	0.08 - 0.10	0.14 - 0.18	0.12 - 0.21	0.16 - 0.18
females
leg II length index	1.5 - 2.2	1.4 - 1.7	1.3 - 1.6	1.1 - 1.3
AME size index	0.067 - 0.068	0.060 - 0.067	0.061 - 0.087	0.038 - 0.053
PME interdistance index	1.88 - 2.26	1.69 - 1.87	1.35 - 2.09	1.46 - 2.33
clypeus height index	0.09 - 0.10	0.15 - 0.18	0.11 - 0.18	0.16 - 0.18

Table 1. Morphometric indices in Ebo -like philodromid genera. Leg II length index = length femur II/femur I; AME size index = diameter AME/CW; PME interdistance index = PME-PME/PME-PLE; clypeus height index = ClyH/CW.