Hortipes castor, BOSSELAERS & JOCQUÉ, 2000

BOSSELAERS, JAN & JOCQUÉ, RUDY, 2000, Hortipes, A Huge Genus Of Tiny Afrotropical Spiders (Araneae, Liocranidae), Bulletin of the American Museum of Natural History 2000 (256), pp. 4-4 : 4-

Hortipes castor , new species Figures 9f–i , 11b ; Map 2

TYPES: Male holotype: sieved from litter 1 km N of Matema, first canyon N with permanent water, Livingstone Mountains , Tanzania, S09°30', E34°03' (13 November, 1991; R. Jocque´) ( MRAC 173.423 ). Paratypes: 1♀ ( MRAC), 16, 1♀ ( AMNH) together with holotype ; 16 by Winkler extraction of sieved litter, same collection data ( MRAC) ; 16 sieved from litter 3 km S of Matema, fourth canyon S with permanent water, Livingstone Mountains , Tanzania, S09°30', E34°03', (15 November, 1991; R. Jocque´) ( MRAC) ; 16, 1♀ captured 7 km N of Matema, large canyon in Livingstone Mountains , Tanzania, S09°30', E34°03' (16 November, 1991; R. Jocque´) ( MRAC) .

ETYMOLOGY: Because this species is the smallest of two very similar species, it is named after the second­brightest first­magnitude star in the constellation Gemini.

DIAGNOSIS: Males of H. castor are recognized by the presence of an apophysis on palpal pa in combination with an evenly curved RTA and a MA that is visible over only a very short distance (both in ventral view); H. pollux males are very similar but differ by the sharply bent RTA and a much longer stretch of MA visible in ventral view. Females can be recognized by a very simple vulvar structure with straight ID running in posterior direction and globular ST1.

MALE: Measurements. Total length 1.94; carapace 0.81 long, 0.68 wide; length of fe: I 0.62, II 0.65, III 0.51, IV 0.73. Leg spination. Fe: I rv 2; IV plt 0 rlt 0; ti: I, II vsp 5; mt: III plt 0 vt 0 rlt 0; IV plt 0–1 vt 1 rlt 1. Coloration. Carapace orange yellow, paler around fovea. Chelicerae orange yellow. Sternum pale yellow, bordered with orange yellow. Abdomen very pale whitish yellow, without any pattern. Legs yellow. Palp. Patella with short, almost straight, retrolateral apophysis whose distal end passes smoothly into basal part; ti with evenly recurved, sharp RTA; cymbium elongate without prolateral

34 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY NO. 256 2000 BOSSELAERS AND JOCQUÉ: HORTIPES 35

width over almost entire length; MA originating on distal extremity of tegulum, thin, and slightly tapered from base to tip, only base visible in ventral view, reaching RTA or enlarged base, fairly thin and short, distal part appressed against MA (fig. 9f–h).

FEMALE: Measurements. Total length 2.73; carapace 1.03 long, 0.86 wide; length

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vsp 6; mt: III plt 0 vt 0 rlt 0; IV plt 1 vt 1– 2 rlt 1. Coloration. Carapace yellow, chelicerae pale yellow. Sternum pale yellow. Abdomen off­white, without pattern. Legs yellow. Genitalia. Vulva: entrance of ID anterior to globular ST1, IDs straight, running parallel to each other along symmetry axis in posterior direction, connected to ST1 with a semicircular bend. A short distance from entrance, ID is associated with glandular structure connected with the lumen through a series of pores (figs. 9i; 11b).

VARIABILITY: The number of mt IV plt spines in males (0 or 1) and mt IV vt spines in females (1 or 2), as well as the transparency of the vulva and the extent of the posterior bend of ID, are variable.

DISTRIBUTION: Livingstone Mountains, Tanzania.

Figures

Map 2. Distribution of Hortipes species in Tanzania. Hortipes angariopsis z, H. bjorni v, H. castor •, H. creber h, H. cucurbita ^, H. delphinus., H. exoptans, H. fastigiensis #, H. narcissus Δ, H. leno, H. libidinosus * H. mulciber, H. ostiovolutus n, H. platnicki D, H. pollux O, H. salticola V, H. scharffi, and H. stoltzei y.

Fig. 9. a. Hortipes platnicki, new species, epigyne. b–e. Hortipes pollux, new species. b. Male palpal pa and ti, dorsal view. c, d. Male left palp, ventral and retrolateral views. e. Epigyne. f–i. Hortipes castor, new species. f. Male palpal pa and ti, dorsal view. g, h. Male left palp, ventral and retrolateral views. i. Epigyne. j–l. Hortipes salticola, new species. j, k. Male right palp, ventral and retrolateral views. l. Epigyne. m. Hortipes exoptans, new species, epigyne. Scale lines: 0.25 mm.

Fig. 11. a. Hortipes platnicki, new species, vulva, ventral view. b. Hortipes castor, new species, vulva, ventral view. Arrows indicate ID entrances. c. Hortipes pollux, new species, vulva, ventral view. d. Hortipes ostiovolutus, new species, vulva, ventral view. e. Hortipes salticola, new species, vulva, ventral view. Arrows indicate ID entrances. f. Hortipes fastigiensis, new species, vulva, ventral view. Scale line: 0.1 mm.