A Revision of the Afrotropical Species of Festucula Simon, 1901 (Araneae: Salticidae)

ABSTRACT The Afrotropical species of the jumping spider genus Festucula Simon, 1901 are revised. The genus now contains eight species. Three new species, F. haddadi sp. n. (♂♀ from South Africa), F. leroyae sp. n. (♂♀ from South Africa and Namibia) and F. robustus sp. n. (♂♀ from South Africa) are described. F. australis Lawrence, 1927 is removed from its synonymy with F. festuculaeformis (Lessert, 1925). F. lineata Simon, 1901, previously treated as nomen dubium, is revalidated and redescribed. Three further species, F. australis Lessert, 1933, F. festuculaeformis Lessert, 1933 and F. lawrencei Lessert, 1933, are redescribed.


INTRODUCTION
The genus Festucula has an Afrotropical distribution, except for F. vermiformis Simon, 1901, which has been recorded from Egypt, Sudan and Israel (Proszynski 2003). The genus has a strong association with grasses and displays several co-evolved, adaptive characteristics such as a very elongate abdomen, a flat carapace, and light-to darkbrown longitudinal bands along the carapace and abdomen, all of which aid crypsis in grasses. It seems that evolutionary selection for these adaptive traits has been strong in grasslands as they have independently evolved in several other unrelated spider genera typically found in habitats dominated by graminoids, including Runcinia (Thomisidae), Tibellus (Philodromidae) and Poachelas (Trachelidae).
The taxonomic history of Festucula starts with E. Simon, who erected the genus in 1901 to accommodate F. vermiformis (female, from Egypt) and F. lineata (female, from Senegal). The period between 1923 and 1941 mainly relates to the work by R. de Lessert, who described Pseudicius festuculaeformis (male only) in 1924 and later transferred it to Festucula (Lessert 1933). He also described the male of F. lawrencei in 1933. Lawrence (1927) described F. australis from Namibia while Berland and Millot (1941) described F. monticola from Guinea and provided a short bibliography for the six known species of the genus.
Currently, only three valid species are included in the genus: F festuculaeformis, F. lawrencei and F. vermiformis (Platnick 2014). The synonymy of F. australis with F. festuculaeformis seems to be erroneous, in spite of Lessert identifying the male from Congo as Pseudicius festuculaeformis instead of F. australis. Moreover, the records of F. lawrencei from Tanzania, which almost completely correspond with the type locality of F. festuculaeformis, are also erroneous. This study therefore aims to (1) diagnose and (re)describe seven Afrotropical species of the genus Festucula on the basis of the (re) examination of types and all available material, (2) map species distributions, and (3) describe three new species from South Africa and Botswana.

MATERIAL AND METHODS
This work is based on material deposited in museums in South Africa and Europe. Specimens for this study were borrowed from the following museums ( A total of 287 specimens were examined. Specimens were studied in ethanol and their coloration refers to that of preserved specimens. All drawings were made with the aid of a reticular eyepiece attached to an MBS-10 stereomicroscope. Digital images were taken with an Olympus SZX16 with attached Olympus E-520 camera and Zeiss Stemi 2000. Images were stacked using the CombineZP and Helicon Focus software. Microphotographs were taken with a Hitachi TM-1000 scanning electron microscope: material was mounted using adhesive and dried for two days. The drawings were edited in Adobe Photoshop. Left palps were illustrated except for Figures 29-31, 33-34 and 77-81, where the right palps were mirrored. If locality co ordinates were not provided on data labels or were not available in the institutional databases, they were traced using the Geographical Names list (http://www.geographic.org) and old topographic maps, and are presented in square brackets.
The following abbreviations are used in this paper: AG -accessory glands PME -posterior median eyes ALEanterior lateral eyes PLE -posterior lateral eyes AMEanterior median eyes Pt -patella Fm -femur Tb -tibia LTA -Mt -lateral tibial apophysis metatarsus VTA -ventral tibial apophysis The sequence of leg segments in measurement data is as follows: femur + patella + tibia + metatarsus + tarsus. All measurements are in millimetres. Leg spination follows Ono (1988). TAXONOMY Genus Festucula Simon, 1901 Type species: Festucula vermiformes Simon, 1901, by original designation.
Description: Medium-sized spiders, total length 4.7 to 9.2 mm. Sexes alike in general body shape and coloration, sometimes with sexual dimorphism in size. Carapace very low, height is only 25-30 % of its length. Eyes: AME largest, PME about midway between ALE and PLE, slightly closer to PLE, ocular quadrangle between 42 % and 47 % of carapace length. Clypeus very low. Chelicerae small, unidentate, with two promarginal teeth and one retromarginal tooth. Maxillae long, slightly curved, convergent. Labium rectangular, longer than wide. Pedicel medium, usually visible in dorsal view. Abdomen very long and narrow, slightly bent downwards at its rear end (Fig. 1). Width is between 19 % and 30 % of its length. Legs: leg I very long and robust, all legs and palps with very long bristles. Leg formula: males and females I, IV, II, III or I, IV, III, II. Leg spination: uniform in both sexes, pattern: leg I -Tb v 0-1-1-1 or 0-1-1-1-0; Mt v 0-2-2ap; leg II -Mt v 1-2ap; leg III -Mt v 0-1ap; leg IV -Mt v 0-1ap. Some species and sexes without spines on legs II, III, IV (i.e. spination only on leg I, e.g. F. lawrencei; or spination on leg I and III/IV, e.g. both sexes of F. festuculaeformis, females of F haddadi and F robustus).  Stridulatory organs (sensu Maddison 1987): present in both sexes and represent a legcarapace stridulatory mechanism, with narrow band of 7 -9 seta-bearing tubercles on carapace below lateral eyes and 4 -6 seta-bearing tubercles on prolateral surface of femora of leg I (Figs 5-7, arrowed). Number of tubercles on carapace and femora varies within species and sexes. Male palp: femur with a small bulge on its inner lateral surface (Fig. 2,arrowed); tibia short, with curved ventral tibial apophysis (VTA) and relatively straight retrolateral tibial apophysis (LTA) (Fig. 3,arrowed); cymbium oval; embolus short, slightly curved, originating prolaterally distally on tegulum; tegulum with prolateral basal lobe. Female genitalia: simple, epigyne a flat plate, with a pair of copulatory pores situated in two depressions in the lower part of epigyne; insemination ducts short, broad at entrances, with long accessory glands (AG) often located near entrances (Fig. 4,arrowed). Composition: Festucula Simon, 1901 includes the following eight species: F. australis Lawrence, 1927 F. festuculaeformis (Lessert, 1925) F. haddadi sp. n. F. lawrencei Lessert, 1933 F. leroyae sp. n. F. lineata Simon, 1901F. robustus sp. n. F. vermiformis Simon, 1901 Distribution: Throughout Africa and the Levant (Fig. 26).  (Lessert, 1925) -Angle between embolus and apical end of tegulum less than 45° (Fig. 17, arrowed) .   (Lessert, 1925) Festucula australis Lawrence, 1927 Figs 14, 22, 27-44 Festucula australis Lawrence, 1927 Diagnosis: The male of this species is most similar to that of F. lineata, but can be distinguished by the shape of the ventral tibial apophysis that is not bifurcated and has a big apical swelling (Figs 30-31). The female of F. australis resembles that of F. vermiformis and can be distinguished by the length of the middle part of the insemination ducts-long in F australis (Fig. 22) and short in F vermiformis (Fig. 23)-and the position of the thin and long accessory glands of spermathecae, which are situated in the middle part of the insemination ducts in F vermiformis (Fig. 23), while posteriorly in F. australis (Fig. 35,arrowed    Distribution: DR Congo, Angola and Namibia (Fig. 26).

Key to species of Festucula
Comments: Specimens from Angola are smaller in body size than those from DR Congo, but their palp sizes are the same. All exemplars from the west coast of Africa belong to F. australis. These were previously identified by Wesolowska as F festuculaeformis on the basis of Lessert's erroneous identification of a male from Faradje (DR Congo) as Pseudicius festuculaeformis and the suggestion that Lessert's drawings are not fully comparable (see Wesolowska 1992: 50). The shape of the tibial apophysis and the number of teeth on the inner edge of the LTA are species-specific (contra Wesolowska 1992).
Festucula festuculaeformis (Lessert, 1925)  Diagnosis: F. festuculaeformis resembles F. haddadi sp. n. The male can be distinguished by the shape of its tibial apophysis: VTA is swollen distally (Fig. 48) and the LTA is dorsally concave (Fig. 49, arrowed), compared to the less swollen VTA (Fig. 64) and dorsally straight LTA in F. haddadi sp. n. (Fig. 64, arrowed). The embolus sits at c. 45° to the distal margin of the tegulum in F. festuculaeformis (Fig. 45), while the angle is much more acute in F. haddadi sp. n. The female can be distinguished by the structure of the spermathecae, characterised by the long, thin middle part of the insemination ducts (Fig. 52).
Diagnosis: F haddadi sp. n. resembles F festuculaeformis. The male can be distinguished by the shape of tibial apophysis, with its broad VTA, almost without any swelling distally (Fig. 65) and with a dorsally straight LTA (Fig. 64), instead of the more swollen distal part of the VTA (Fig. 48) and dorsally concave LTA in F festuculaeformis (Fig. 49). The female can be distinguished by the structure of spermathecae, with the short, broad middle part of the insemination ducts (Fig. 68).
Coloration (Figs 84-87): Carapace low, flat, brown with median yellow bands, laterally with two longitudinal light-brown bands covered with white adpressed hairs. Clypeus brown, very low, covered with white hairs (Fig. 87). Chelicerae brown. Clypeus and sternum yellow-brown. Abdomen yellow (Fig. 85), dorsum with two longitudinal brown stripes (Fig. 84 Etymology: This species is named after Astri Leroy, the chairperson of the non-profit organisation "The Spider Club of Southern Africa" and veteran spider collector. Diagnosis: This species resembles F. robustus sp. n. in body coloration and the structure of the epigyne and spermathecae . The female differs in the relatively short and compact spermathecal ducts (Fig. 96). The male palp is close to that of F. lawrencei, but differs in the shape of ventral tibial apophyses-LTA dorsally straight and relatively broad (Figs 89, 92). See also comments under the 'Diagnosis' of F. lawrencei. Coloration (Figs 97-100): Carapace low, flat, brown with two lateral yellow bands, covered with white adpressed hairs, with dark-brown ocular area. Ocular area with thin brown longitudinal stripe and yellow patch behind AME. Clypeus brown, very low, covered with white hairs (Fig. 100). Chelicerae yellow-brown. Sternum yellow. Abdomen grey-yellow, ventrally with caudal part (approx. %) brown (Figs 98-99). Dorsum with broad longitudinal brown band (Fig. 97). Booklungs yellow. Spinnerets brown. Legs I long and robust, brown. The rest of legs yellow. Palps brown-yellow. All legs and palps covered with long thin bristles. Palpal structure as in Figs 88-92.
Female. Coloration (Figs 101-103): Carapace low, brown, with black eye field, with small dark patch behind AME and two lateral yellow bands covered with white adpressed hairs. Clypeus very low, brown, covered with white hairs. Chelicerae brown. Sternum brownish-yellow. Abdomen grey-yellow, ventrally caudal part (approx. %) brown . Dorsum with broad brown longitudinal band (Fig. 101). Booklungs yellow. Spinnerets brown. Legs I long and robust, yellow-brown. Femora I yellow ventrally, yellow-brown dorsally, dark brown pro-and retrolaterally. Tibiae I dark brown distally. Metatarsi and tarsi dark brown. The rest of legs and palps yellow. All legs and palps covered with long thin bristles. Structure of epigyne and spermathecae as in Figs  Distribution: Western Africa from Senegal to Nigeria (Fig. 26).
Comments: F. lineata was described by  based on a single female from Dakar, Senegal. Later, Fage (1923) described the male from Guinea. Wesolowska (1992) treated this species name as nomen dubium, pointing out that 'In the MNHN collection there are only two immature specimens. The brief and cursory original description is inadequate for certain identification of this species. Similarly the drawing of the syntype's epigyne in Lessert (1933) is too schematic to be helpful in the species identification, Diagnosis: This species resembles F. leroyae sp. n. The male differs in the shape of the ventral tibial apophysis-broad and bent laterally at 90° (Fig. 113). The female differs in the longer and less compact spermathecal ducts (Fig. 119).  Coloration (Figs 121-124): Carapace low, dark brown, with black eye field, narrow median light-brown stripe and small patch behind AME, with two lateral yellow bands covered with white adpressed hairs. Clypeus very low, brown, covered with white hairs (Fig. 124). Chelicerae dark brown. Sternum brown. Abdomen yellow-grey, with ventral medial brown stripe, ventrally, caudal part (approx. %) brown . Dorsum with broad brown longitudinal band (Fig. 121). Booklungs yellow. Spinnerets brownishyellow. Legs I long and robust, brown. The rest of legs brownish-yellow. Palps brown. All legs and palps covered with long thin bristles. Palpal structure as in Figs 113-117.