Arachnology (2013) 16 (2), 68 72 A new species of the African spider genus Lathrothele Benoit, 1965 (Araneae: Dipluridae) from Gabon Christian M. Bäckstam Department of Entomology, Box 50007, SE-104 05 Stockholm, Sweden email: christian.backstam@nrm.se Bastian Drolshagen Institute of Environmental Sciences, University of Koblenz-Landau, Fortstraße 7, 76829 Landau, Germany email: drolshagen@dipluridae.de Michael Seiter Department of Integrative Zoology, Faculty of Life Science, University of Vienna, Althanstraße 14, A-1090 Vienna, Austria email: seitermichael@hotmail.com Summary A new species of the African ischnotheline genus Lathrothele Benoit, 1965 is described, from a male and female from Gabon, as Lathrothele mitonae the genus with coiled receptacula seminis in the female. Introduction Benoit (1965) described the genus Lathrothele with the type species Lathrothele grabensis Benoit, 1965, which was also later displayed in Raven (1983). In the same paper, Benoit described Lathrothele marmoratus Benoit, 1965, which was listed as Latrothele marmorata by Brignoli synonym of Lathrothele grabensis by Coyle (1995). Benoit (1965) also described two more species: Lathrothele cavernicola Benoit, 1965 and Lathrothele jezequeli Benoit, 1965. He also considered the species described as Ischnothele catamita Simon, 1907 to belong to Lathrothele and transferred it to this genus: Lathrothele catamita (Simon, 1907). In his revision of the subfamily Ischnothelinae, Coyle (1995) described and illustrated all known species of Lathrothele (MS) collected a new species of Lathrothele near the Mitone known species of the genus with coiled receptacula seminis in the female.
C. M. Bäckstam, B. Drolshagen & M. Seiter 69 Material and methods The material was examined using a stereo-zoom microscope. Illustrations were obtained as vectorized graphics from digital images using the graphical software Adobe Illustrator. All appendage and body measurements were made using an ocular micrometer. All measurements are given in millimetres. Bulbi were recorded in prolateral and retrolateral views. Leg lengths are considered to be the sum of all segments from femur (proximal) to tarsus (distal). The width of the prosoma was measured at the level of the fovea and its length from the pedicel to the base of the chelicerae. The lengths of non-sclerotized body parts such as the opisthosoma are considered to be approximate measurements only. The counts of spines on the legs and pedipalps are given as follows: Appendage: segment, position, amount. Abbreviations: ALE = anterior lateral eyes, AME = anterior median eyes, Cy = cymbium, d = dorsal, Fe = femur, ITC = inferior tarsal claw, Mt = metatarsus, Pa = patella, Pd = pedipalp, pl = prolateral, PLE = posterior lateral eyes, PLS = posterior lateral spinnerets, PME = posterior median eyes, PMS = posterior median spinnerets, rl = retrolateral, STC = superior tarsal claw, Ta = tarsus, Ti = tibia, v = ventral. Abbreviations and measurements of male palpal organ and other meristic features follow Coyle (1995) and are as follows: BD = bulbus width, CDR = retrolateral apophysis, from apex of prolateral cymbial lobe to tip of male cymbium (including apophysis) in prolateral view, MAD = distance along line of male metatarsus I length from proximal end of metatarsus to intersection with perpendicular line passing through the apex of tallest part of metatarsal apophysis in retrolateral view, PL = length of male palpal organ, SL = sternum length, SW = sternum width, TAL = distance from distodorsal angle of male tibia I mating apophysis to base of apophysis in retrolateral view. Acronyms of museums and collections national d Histoire naturelle, Paris; MRAC: Musée royal Museum, Wien. Examined type material: Only the male holotype and female paratype of (see data in section below), due to the revision by Coyle (1995) and the obvious differences between and the congeners. Type material: Lathrothele grabensis Benoit, 1965, male holotype from Katondi, Territory Lubero, Kivu, Congo and female allotype from source of the Talia River, Lubero, Kivu, Congo, in MRAC (92.267, 73.862). Lathrothele marmoratus Benoit, 1965, female holotype and female paratype Lathrothele cavernicola Benoit, 1965, male holotype and female allotype from Kele, grottos near Thysville, Congo, in MRAC (127.109, 127.110). Lathrothele jezequeli Benoit, 1965, male holotype and female allotype from station Pa 88, Ischnothele catamita (9086)., male holotype and female paratype from Mitone River, between the cities of Data for type localities follow respective original description, i.e. Simon (1907) and Benoit (1965). For Lathrothele grabensis, Lathrothele cavernicola and Lathrothele jezequeli, where numerous of paratypes were designated, only the holotype and the female allotype are given. For a complete list, see Benoit (1965) and Coyle (1995). Lathrothele Benoit, 1965 Lathrothele Benoit, 1964: 417 (nomen nudum). Lathrothele Benoit, 1965: 113 (type species by original designation Lathrothele grabensis Benoit). Raven, 1983: 552; 1985: 78. Platnick, 1989: 80; 1993: 90. Coyle, 1995: 95. Latrothele [sic] Brignoli, 1983: 126. Included taxa: Lathrothele catamita (Simon, 1907), Lathrothele cavernicola Benoit, 1965, Lathrothele grabensis Benoit, 1965, Lathrothele jezequeli Benoit, 1965, Lathrothele mitonae sp. nov. Diagnosis: Males of Lathrothele are distinguished from those of the other Old World genera Indothele Coyle, 1995 and Thelechoris Karsch, 1881 by the shape of the palpal organ, with the embolus being less abruptly tapering from 321, 322), the large size and subterminal position of the tibia the presence of an apophysis on metatarsus I (Fig. 3; Coyle Thelechoris), and the position and shape of the metatarsus I apophysis (Fig. Indothele). Females are distinguished from those of other Old World genera by having a relatively large number of retrolateral cheliceral denticles (CDR(100)/CL = 476 1576 v. 14 332). For a more extensive diagnosis, and distinction of the genus from other ischnotheline genera, see Coyle (1995). Segment Leg I Leg II Leg III Leg IV Pd Ta 1.13 1.30 1.55 1.61 0.95 Mt 1.54 1.83 2.20 2.63 Ti 1.33 1.58 1.83 2.03 0.75 Pa 1.00 1.05 0.93 1.13 0.59 Fe 1.87 1.95 2.08 2.00 1.15 Total 6.87 7.71 8.59 9.40 3.44 Table 1: Measurements of leg and pedipalp segments of male holotype of Segment Leg I Leg II Leg III Leg IV Pd Ta 0.90 0.78 0.78 1.03 0.70 Mt 1.05 0.93 1.53 1.95 Ti 1.08 1.20 1.30 1.83 0.50 Pa 0.63 0.48 0.48 0.84 0.38 Fe 1.58 1.68 1.70 1.93 1.10 Total 5.24 5.07 5.79 7.58 2.68 Table 2: Measurements of leg and pedipalp segments of female paratype of
70 Lathrothele from Gabon 1 2 3 4 5 6 Figs. 1 6: 1 5: Holotype male. 6: Paratype female. 1 Right palp, retrolateral view; 2 Right palp, prolateral view; 3 Distal Ti and proximal Mt I, retrolateral view; 4 Sternum, labium and maxillae, ventral view; 5 Carapace, dorsal view; 6 Vulva, dorsal view. Scale bars 1 5: 1 mm. 6: 0.5 mm. Description. Mostly following Coyle (1995). Body size small to medium (males and females CL = 2.02 4.77 and CL = 1.80 6.31, respectively). Carapace with moderately dense covering of thin recumbent to semirecumbent setae; usually 2 (rarely 1, 3 or 4) foveal bristles; semierect setae on lateral edges of carapace long and strong. Pars cephalica slightly to moderately elevated above pars thoracica (Coyle 321) semicylindrical or slightly swollen ventrally and proximally; erect ventral bristles vary in length and posi- 312, 321) with 3 6 spines; tip without bristles. Palpal organ elongate; embolus long, gradually tapering and upcurved Male tarsi pseudosegmented; tarsus I with 0 2 (males) or 0 5 (females) spines. Male tibia I approximately cylindrical or considerably swollen dorsally, with spineless pointed mating apophysis ventrally at distal end (Fig. 3; Coyle 1995, apophysis ventrally or small and angular simple or double- 281, 309, 310, 320). One or two receptacula seminis on each Type material a few metres beside a bridge in a secondary rainforest
C. M. Bäckstam, B. Drolshagen & M. Seiter 71 February 2011. Etymology singular, refers to the Mitone River, where the type material was collected. Diagnosis: Males and females of Lathrothele mitonae differ from the other species by the smaller body size (male CL = 2.02 v. CL = 2.54 4.77 and female CL = 1.80 v. 2.16 6.31). Males of Lathrothele mitonae are distinguished from those of other species by a smaller mating apophysis on Ti I (TAL(100)/CL = 7.4) (Fig. 3). Males are distinguished from those of Lathrothele grabensis and Lathrothele cavernicola by the unswollen Ti I, upcurved shape of the mating apophysis on Ti I, and a smaller apophysis on ventral Mt I (Fig. 3). Males are distinguished from those of Lathrothele cavernicola and Lathrothele jezequeli by a shorter and more slender palpal organ (PL(100)/BD = 296), and from Lathrothele jezequeli by a shorter cymbial apophysis Mt I being double-keeled. Females differ from those of other species by the broader sternum (SW(100)/SL = 97). Females are distinguished from those of other species by the shape of the receptacula seminis being coiled instead of straight (Fig. 6). Description of holotype male: Colour in alcohol: carapace (length 2.02, width 2.10) light yellow with dark pattern; sternum (length 1.10, width 1.13), chelicerae and labium as carapace, but without pattern; legs as carapace, but with dark brown band pattern distally and proximally on tibiae, medially on patellae and distally on femora; opisthosoma (length 2.60, width 1.70) without dorsal pattern, with many long, strong setae and interspersed short, soft setae. Carapace covered by many setae, fringed by light, long setae; striae distinct; fovea pitlike; one pair of foveal bristles; clypeus (length 0.05) present and prominent. Eyes: AME largest, ALE slightly smaller, PME and PLE smallest; ALE oval (Fig. 5). Sternum with three pairs of sigillae: anterior pair at height of rl coxa I; medial pair at height of rl coxa II; posterior pair at height of rl coxa III, largest; all marginal. Chelicera dorsally and retrolaterally with band of setae, ventrally with two rows of teeth on margin. Labium rectangular, wider than long, without cuspules. Maxilla ventrally with numerous cuspules on proximoventral anterior corner in approximately 45 degrees to base (Fig. 4); serrula present. distally with slightly upcurved, tapering embolus (Figs. 1 2); BD = 0.23, PL = 0.68; spination: Cy v2pl2, Ti and Pa prolaterally and dorsally with numerous, strong macrosetae. Legs: all tarsi pseudosegmented along complete segment, aspinose, without scopula, with ventral rows of setae; three claws, paired STC with one row of teeth, ITC without teeth; measurements as in Table 1; Mt I ventrally with ventrally double-keeled apophysis at 0.3 away from base (MAD = 0.38); Ti I ventrally with subterminal mating apophysis (length 0.28, TAL = 0.15); spination: I: Mt v2, Ti v2rl2d3, Pa d3; II: Mt v2d4, Ti v3pl2d4, Pa d1; III: Mt v3rl3d2, Ti v3pl2rl1d1, Pa d5; IV: Mt v1pl1rl3d3, Ti v3pl1rl2d4, Pa rl2d4; femora with macrosetae. Four spinnerets: PMS consisting of a single segment (length 0.55); PLS consisting of three segments: proximal (length 0.93); medial (length 0.88) shortest; distal (length 2.23) longest, Description of paratype female: As for male, but carapace (length 1.80, width 1.68), sternum (length 0.98, width 0.95) smaller, opisthosoma (length 3.40, width 2.55) light grey with indistinct dorsal white pattern and clypeus (length 0.08) slightly larger. Pedipalps: left pedipalp damaged; right palpal tarsus with single claw, 1 row of teeth; spination: Ta v4, Ti v2pl1, Pa d2. Legs: left legs III and IV missing; all segments ascopulate; tarsi ventrally with rows of setae; patellae with retrolateral protuberance; measurements as in Table 2; spination: I: Mt v3pl1, Ti v4pl2d1, Fe rl2; II: Mt v4pl3, Ti v3pl2d1, Fe rl1; III: Mt v4pl4d2, Ti v2pl3d3; IV: Mt v4pl3d2, Ti v5pl3d3, Pa rl2d3. Spinnerets damaged, proximal third of distal segment still present, consisting of three segments: proximal (length 0.75), medial (length 0.63), distal broken. Vulva consisting of four receptacula seminis, each medially coiled and with apical lobe; strongly sclerotized apically (Fig. 6). Distribution: Only known from the type locality. Ecology: The known specimens were collected from a secondary rainforest in central Gabon. The area is close to a small river, next to the road and, according to our information, this part of the forest was clear cut approximately eight years ago. The canopy is not completely closed and sunlight ~80% but, nevertheless, it is very dry on the ground. During the day the temperature reaches 28 C. At a height of approximately 90 cm from the ground, the spiders build their webs where the plants are branching. The web is loosely woven and attached to leaves, roots, debris, and similar. The tubular retreat is around 15 cm long and the retreat opens directly into the capture web, where the spider sits. Adult web size range is very small, 15 20 cm² in total. It appears that the mating period is at the beginning of the dry season. In the laboratory, three egg sacs were produced by two females between March and May. The brood sizes of the egg sacs ranged from 39 to 45. Acknowledgements We thank Christoph Hörweg for depositing the type specimen of in the collection comments on the manuscript. References Orthognatha) I. Genres Euagrus Ausserer et Thelechoris Karsch. Revue de Zoologie et Botanique africaines 70: 417 426. Orthognatha) II. Genres Lathrothele nov. et Macrothele Ausserer. Revue de Zoologie et Botanique africaines 71: 113 128. A catalogue of the Araneae described between 1940 and 1981. Manchester: Manchester University Press. subfamily Ischnothelinae (Araneae, Dipluridae). Bulletin of the American Museum of Natural History 226: 1 133.
72 Lathrothele from Gabon Advances in spider taxonomy 1981 1987: A supplement to Brignoli s A catalogue of the Araneae described between 1940 and 1981. Manchester: Manchester University Press. Advances in spider taxonomy 1988 1991: With synonymies and transfers 1940 1980 Musée Royal de l Afrique Centrale (Dipluridae, Hexathelidae, Ctenizidae: Araneae). Revue de Zoologie africaine 97: 549 562. cladistics and systematics. Bulletin of the American Museum of Natural History 182: 1 180. d Afrique. 1re partie. Annali del Museo civico di storia naturale di Genova 3: 218 323.