A revision of the genus Pochytoides Berland & Millot, 1941 (Araneae: Salticidae), with descriptions of six new species

The concept of the jumping spider genus Pochytoides Berland & Millot, 1941 is reviewed, based on the examination of described and undescribed species. Pochytoides is elevated from the subgeneric to the generic rank and a short diagnosis and description of the genus are presented. Redescriptions or descriptions of all species are provided together with a key to the species. Two new combinations are proposed: Pochytoides perezi (Berland & Millot, 1941) comb. nov. and P. poissoni (Berland & Millot, 1941) comb. nov. (both from Pochyta). Pochyta remyi Berland & Millot, 1941 originally placed in the subgenus Pochytoides is excluded; new combination Thiratoscirtus remyi (Berland & Millot, 1941) comb. nov. is proposed for it (but its generic status is uncertain). Six new species are described: Pochytoides monticola sp. nov., P. obstipa sp. nov., P. lamottei sp. nov., P. patellaris sp. nov., P. securis sp. nov. and P. spiniger sp. nov. The genus has a West African distribution.


Introduction
pattern of the genitalic structure in Pochytoides is unique and clearly separates the genus from the other thiratoscirtine genera (see diagnosis of the genus below).

Material and methods
All spiders considered here have been collected in Guinea. Three species, P. perezi comb. nov., P. poissoni comb. nov. and P. remyi, were described by Berland & Millot (1941) and were collected by J. Millot in 1937 in the vicinity of Macenta (Guinea). Types of these species are kept in the collection of MNHN.
The specimens from the Nimba Mountains were collected during the expeditions led by M. Lamotte (with collaborators) in the years 1942, 1951, 1956 and in 1961. A substantial part of this collection is kept in MNHN and has already been examined by Rollard & Wesołowska (2002). Another part of the material, used in the present study, is deposited in the NHM and has not been studied so far. Unfortunately, the majority of labels do not contain precise data on localities and dates, referring only to the 'Nimba Mts'. Additional abundant material was collected by Arnaud Henrard (with associates) during expeditions to the Nimba Mountains in 2011 and 2012. These newly collected specimens were deposited in the MRAC.
Six new species described in this article come from the latter two collections and their type specimens are deposited in NHM and MRAC.
Male-female matching was based on the co-occurrence of specimens, but in some cases more than one species was found in a single vial. Comparison of the embolus length to the length of the epigynal copulatory ducts was helpful in these cases, but it is still possible, that the matched sexes actually do not belong to the same species.
The specimens are preserved in 70% ethanol and were examined in ethanol. Some of the studied specimens are heavily bleached and the colours given in the descriptions may differ from those in the living spiders. The drawings were made with the aid of a reticular eyepiece attached to a stereo microscope. The epigynes and the male pedipalps were removed for study. The epigynes were macerated in cold 5% KOH for 24 hours, dehydrated with 100 ethanol, cleared in xylene and put in eugenol in temporary mounts. After examination, the genitalia were placed in micro-vials with ethanol and stored in the vials containing the specimens from which they had been removed. Terminology is standard for Araneae. The term 'spine' is used for a stout, rigid, pointed seta. Specimens were measured as in Metzner (1999), dimensions are given in millimetres. A Nikon Coolpix 8400 mounted on the stereo microscope was used to take digital photos, which were stacked using Helicon Focus image stacking software to increase the depth of fi eld.

Differential diagnosis
The male palp is similar to that of P. spiniger sp. nov. in having a sinusoid anterior lobe of the bulb, but may be recognized by the strongly sclerotized keel on the prolateral edge of this lobe and the absence of a spine at the base (compare Fig. 1A-C with Fig. 13A-C). The female slightly resembles those of P. securis sp. nov. and P. spiniger sp. nov. They share an epigyne in which the distance between the lateral edges of the atria is smaller than the distance between the lateral edges of the spermathecae. However, P. lamottei sp. nov. may be distinguished by the atria, which are cup-shaped (narrower in the other species,

Etymology
The specifi c name is Latin, meaning a dweller among the mountains, it refers to the occurrence of the species in montane habitats.

Differential diagnosis
The male differs from the other males of Pochytoides in having a uniquely shaped of the embolic division that is serrated at the tip (Fig. 3A). The female may be distinguished by the form of the epigyne, similar to that of P. perezi comb. nov. and P. obstipa sp. nov., all of which have a wide fi eld occupied by atria. However, P. monticola sp. nov. can be distinguished from P. perezi comb. nov. by the shape of the epigynal depression, which is a narrow horizontal gap (V-shaped in P. perezi comb. nov., compare  GENITALIA. Epigyne with wide but low depression anteriorly and posterior plate with two separated pockets . Atria deep, strongly sclerotized, copulatory canals relatively long (Fig. 4C).

Remarks
Matching of sexes uncertain.

Etymology
The specifi c epithet is Latin for shrunken and refers to the short bulb.

Differential diagnosis
The male of P. obstipa sp. nov. is similar to that of P. monticola sp. nov., but can be distinguished by the shape of the embolic division, which is ribbon-like in the former species (Fig.5A) and serrated in the latter (Fig. 3A). The female is similar to that of P. poissoni comb. nov., sharing the epigyne with paired pockets placed at the level of the spermathecae, but can be distinguished from it by the shape of the shallow anterior depression which does not have a clearly marked anterior edge (Fig. 6A-D) as opposed to a distinct two-arched edge in P. poissoni comb. nov. (Fig. 10A-F). COLOUR AND BODY. Very small spider. Carapace light brown, eyes encircled by dark rings, some dark scales above anterior median eyes. Abdomen ovoid, bleached, beige greyish with traces of white chevrons. Body clothed in delicate colourless hairs, some white hairs on slopes of carapace. Legs dark yellow, bases and tips of their segments slightly darker, femora of fi rst pair of legs brown.

Differential diagnosis
The male is similar to that of P. poissoni comb. nov. in having an embolus with accompanying membrane, but may be distinguished by the presence of a small patellar apophysis (Fig. 7A, C, F-G).  COLOUR AND BODY. Carapace brownish with slopes slightly darker but covered by light hairs. Anterior eyes encircled by fawn scales. Abdomen greyish with large light patch in anterior half and chevrons posteriorly, clothed in fi ne hairs, among them some longer bristles. Legs yellow with darker rings.

Differential diagnosis
The female has an epigyne similar to that of P. spiniger sp. nov., sharing the V-shaped anterior epigynal depression and the absence of pockets, but may be distinguished by having a broader area occupied by the atria than that of P. spiniger sp. nov. in comparison to the area surrounding the spermathecae (compare Fig. 8B-C with Fig. 15A-C).

Male
Unknown.

Differential diagnosis
The male is similar to that of P. patellaris sp. nov. in having an embolus with accompanying membrane, but may be distinguished by the orientation of the embolar tip (retrolateral in P. poissoni comb. nov., prolateral in P. patellaris sp. nov.) and by the absence of a patellar apophysis. The female is slightly similar to that of P. obstipa sp. nov.; both species have an epigyne with paired pockets placed near the epigastric furrow at the level of the spermathecae, but P. poissoni comb. nov. can be separated by the clearly smaller atria and characteristic wavy edge of the atrial area (compare Fig. 10A-F with Fig. 6A-D).  COLOUR AND BODY. General appearance as in Fig. 9A. Carapace abruptly sloping posteriorly (Fig. 9B), covered with delicate colourless hairs, some white hairs on slopes. Anterior medians lack black rings, long bristles near eyes. Fovea visible. Clypeus low, with white hairs. Chelicerae dark yellow, fang short, dentition as in Fig. 9C. Labium, endites and sternum dark yellowish. Abdomen smaller than cephalothorax, oval, yellowish grey (probably bleached) with traces of lighter chevrons in posterior half, some brown bristles on abdominal dorsum, denser at anterior edge. Spinnerets yellow. Legs long, light brown. Ventral spines of tibia and metatarsus extremely long (Fig. 9D). Short, stiff and sharp hairs on ventral surface of fi rst femur.

Redescription
GENITALIA. Pedipalps yellow with white hairs on cymbium, tibia short with short broad retrolateral and prolateral apophyses (Fig. 9F, J) and thin horizontal apophysis on dorsum (Fig. 9H). Embolus nearly straight, only the tip curved to retrolateral side, with large accompanying membrane (Fig. 9E-G, J-K).  COLOUR AND BODY. Shape of body as in male, only leg I shorter. Some white hairs on slopes of carapace. Chelicerae as in male, only retromarginal tooth slightly smaller. Abdominal pattern with more contrast than in male, two parallel light bands on greyish background in anterior part and a few chevrons posteriorly. Legs yellow, darker rings on bases and ends of segments. Retrolateral spine on palpal tarsus (Fig. 10A).
GENITALIA. Epigyne strongly sclerotized, especially in the anterior part, with pair of pockets in front of the epigastric fold (Fig. 10A-F; fi gures show intraspecifi c variation). Internal structure as in Fig. 10G-H, copulatory openings placed in deep atria, small accessory glands connected to spermathecae.

Remark
One male was found together with the holotype in the same vial, but this specimen is not mentioned in the original description.

Etymology
The specifi c name is Latin for axe and refers to the shape of the anterior lobe of the bulb.

Differential diagnosis
The male differs from that of other species in having an unique anterior lobe of the bulb, broadening distally, with a small triangular process on the prolateral edge at mid-length (Fig. 11E). The female is easily recognized from congeners by the unique structure of the epigyne with relatively weakly sclerotized atria and long seminal ducts (Fig. 12A-B). COLOUR AND BODY. General appearance as in Fig. 11A. Carapace dark brown, black line along edges of carapace, white hairs on slopes and on foveal area. Anterior median eyes lack black rings but encircled by fawn scales, fawn hairs on eye fi eld (Fig. 11B). Clypeus brown. Chelicera with an unusually large promarginal tooth (Fig. 11C). Mouthparts brownish, sternum yellow. Abdomen greyish beige to dark brown, with yellow serrated band medially (Fig. 11A), venter dark with four lines formed by white dots. Spinnerets dark. First pair of legs dark brown, metatarsus and tarsus lighter. Other legs brownish with darker femora. Coxae and trochanters of all legs pale.
GENITALIA. Pedipalps brown, cymbium clothed in dense pale hairs. Palpal organ as in Fig. 11D-H, bulb with characteristic wide anterior lobe. Dorsal apophysis slightly broader than in other species. COLOUR AND BODY. Similar to male, slightly lighter coloured. Anterior median eyes encircled by grey scales, grey hairs on eye fi eld. Abdomen yellowish.

Etymology
The specifi c name is Latin, meaning prickly and refers to the presence of spikes at the base of anterior lobe of the bulb.   the epigyne with a V-shaped anterior depression, but may be distinguished by the atrial area narrower than the area occupied by spermathecae (Fig. 15A), quite the opposite to that of P. perezi comb. nov. (Fig. 8A-C).
GENITALIA. Pedipalps clothed in dense whitish hairs. Palpal organ as in Figs 13A-G, 14 C-F. Retrolateral tibial apophysis blunt and wide, dorsal apophysis narrow perpendicular to retrolateral. Bulb triangular with narrowing anterior lobe. Sharp spike on prolateral side of this lobe at its base ( Fig. 13A, C, F), retrolateral margin of the lobe strongly sclerotized basally (Fig. 13B, E). COLOUR AND BODY. Similar to male, abdomen slightly clearer, pattern with less contrast. Legs yellow with brownish rings at bases and ends of segments.
GENITALIA. Epigyne rounded with strongly sclerotized anterior part (Fig. 15A-C). Internal structure as in Fig. 15D, distinctly sclerotized edge around atria, spermathecae relatively large, accessory glands connected visible. (Berland & Millot, 1941) comb. nov. The specimen was examined by Tamás Szűts (pers. com.). It is not a member of Pochytoides and the generic status of the species remains uncertain, requiring further study. The form of the epigyne (Fig. 16) is similar to that of some members of the genus Thiratoscirtus Simon, 1886.

Discussion
Pochytoides is a small genus, currently containing eight species, which are known only from Guinea. Almost all of them are restricted to the Nimba Mountains. The species from the Nimba Mts are probably syntopic, in some cases specimens of 2-3 species were placed in the same vials, so they were possibly collected together. The members of this genus are very similar in body shape, size and colouration. The differences in structure of their genitalia are nonetheless clear, although following the same general pattern. Because these species are closely related and well separated from the other groups, their generic status is postulated based on morphological dissimilarity.
Such a large a number of related species from the Nimba Mts fully supports recognition of this mountain range as an area of exceptional biological richness. The mountains are situated within the Guinean Forests of West Africa biodiversity hotspot, which harbours an especially rich fl ora and fauna with a high level of endemism (UNESCO World Heritage Centre 2016). In recognition of its unique value, the Nimba Range (jointly 180 km 2 ) was declared a Strict Nature Reserve, after Guinea and Côte d'Ivoire became independent. UNESCO proclaimed Mount Nimba a biosphere reserve in 1980, and a World Heritage Site shortly thereafter. This paper is a contribution to the knowledge of the spider diversity of the Nimba Mts and shows a high species diversity of this poorly known genus of jumping spiders.