A juvenile of Depreissia decipiens (with labels “Kinabalu NP, My 6°5'N 116°33'E Poring Hot Springs, A. lagenocarpa 13 A. Floren. 16.9.2006. B 14”, and “WPM DNA voucher d470”) was supplied by Christa Deeleman-Reinhold. Data for 28S from this specimen was added to data from 72 taxa included in the analysis of Maddison et al. (2014), selected to cover the breadth of salticid diversity, and because their 28S sequences were fairly long. Information on those specimens and sequences can be found in Maddison et al. (2014) by following the voucher codes in brackets in the taxon names of Fig. 1.

Figure 1. 

Maximum likelihood phylogenetic tree from 28S sequences, constrained as described in text. Branches labelled by bootstrap percentages from 500 replicates, with selected branches also showing (after “/”) bootstrap percentages for analysis with Eupoa and Agorius removed. Branch length of Agorius abridged to 50% of its actual length. Voucher specimen codes appended in brackets. Cocalodine, spartaeine and lapsiine lineages are colored as in Maddison et al. (2014). Stars mark clades constrained except for the freedom of Depreissia and Agorius.

DNA was extracted from the entire body of a single immature male using a Qiagen DNeasy Blood and Tissue Kit. The specimen was not ground, but several holes were torn into the body wall to allow better penetration of buffers and enzymes. The fragment of 28S was amplified using the Polymerase Chain Reaction on an Eppendorf Mastercycler Thermal Cycler ProS, using TaKaRa Ex Taq and the basic protocols recommended by the manufacturer. Two PCR reactions were conducted, one with primers LS58F and LS998R, the other with primers NLF184/21 and LS1041R (Maddison 2012), both using cycling reaction CI in Maddison (2012: 573). The amplified products were then cleaned, quantified, and sequenced at the University of Arizona’s Genomic and Technology Core Facility using a 3730 XL Applied Biosystems automatic sequencer. Initial base calls and assembly of the four chromatograms into one fragment were made with Phred (Green and Ewing 2002) and Phrap (Green 1999) as orchestrated by Mesquite’s Chromaseq package (Maddison and Maddison 2014, 2015) with subsequent modifications by Chromaseq and manual inspection.

Automatic multiple sequence alignment was performed by MAFFT (Katoh et al. 2002, 2005), run via the align package of Mesquite (Maddison and Maddison 2015). Alignment used the L-INS-i option (--localpair --maxiterate 1000).

Phylogenetic analyses using maximum likelihood were run using RAxML version 7.2.8alpha (Stamatakis 2006a, b). RAxML runs assuming the GTRGAMMAI model were performed with 100 search replicates, to seek maximum likelihood trees. In addition, likelihood bootstrap analysis was performed with 500 bootstrap replicates, each involving a single search replicate. We performed both constrained and unconstrained analyses. The unconstrained analyses used only the data at hand: the 28S gene in the 73 taxa. This unconstrained analysis has the flaw that it fails to consider data from other genes and other taxa, which have convincingly demonstrated the monophyly of many major clades of salticids. Because the gene 28S does not properly resolve some of the deeper relationships of the family (Maddison et al. 2014), this analysis places Depreissia on a faulty background. We therefore also performed analyses that constrained the tree to enforce monophyly of some groups, thus placing Depreissia on a well-supported salticid phylogeny. The full constraints analysis holds the following groups monophyletic as they are well supported by multigene analyses (Maddison et al. 2014): Salticidae, Lyssomanes + Chinoscopus, Asemonea + Goleba + Pandisus, spartaeines + cocalodines + lapsiines, Hisponinae, Salticinae, Amycoida, Salticoida, Bavia + Stagetilus, Astioida, Marpissoida, and Saltafresia. Relationships within those groups were free to vary, and the placements of Depreissia and Agorius Thorell, 1877 were free to move throughout the tree, including within the otherwise constrained clades. Thus, even though these clades were constrained, they could have had bootstrap percentages less than 100% if Depreissia or Agorius had wandered inside or outside them. Another less constrained analysis enforced the monophyly of only the Salticidae. Because Eupoa Żabka, 1985 and Agorius have unusual 28S genes and are unstable in analyses (Maddison et al. 2014), they were excluded in some variant analyses.

Structures of Depreissia myrmex were studied from a specimen deposited in the HNHM (Hungarian Natural History Museum, curator Dr. László Dányi, label data: Araneae-4515: Depreissia myrmex Lessert, 1942: Republic of Congo, Kindamba, Meya, Bangu forest, 1963., leg: J. Balogh & A. Zicsi, det.: Wanda Wesolowska („HNHM Nr. 325”) 3 50'S, 14 30'E). The specimen was examined with an Olympus SZ60 microscope; images were taken with Leica DM2700 M, Nikon Eclipse and Zeiss JENAVAL microscopes. For examination of internal structures, the palp was immersed in absolute ethanol then temporarily cleared with a solution of methyl salicylate (synthetic version of wintergreen oil), fixed with a modified version of Coddington’s temporary mount (Coddington 1983), and photographed with an attached Nikon D300S camera using Helicon Remote®. Multiple stacked images were montaged using the program Helicon Focus®.

Specimens illustrated in the figures are listed in the Appendix. Abbreviations for collections are UBC-SEM (University of British Columbia, Spencer Entomological Collection), HNHM (Hungarian Natural History Museum), CAS (California Academy of Sciences) and ZMUC (Zoological Museum, University of Copenhagen).

The data underpinning the analyses reported in this paper, and the resulting trees, are deposited in the Dryad Data Repository at https://doi.org/10.5061/dryad.gd501.

The embolus of Depreissia wraps around the round bulb, appearing merely as a peripheral black edge (Wesołowska 1997, Deeleman-Reinhold and Floren 2003, Szűts and Wesołowska 2003). In D. myrmex (Figs 2–6, 9–10), the embolus originates at about 6 o’clock (Figs 4, 5e’), then loops three times around the bulb to end near the origin (Fig. 5e’’). The spermophore is fairly narrow throughout (Fig. 5s).

Figures 2–7. 

Male palp of Depreissia myrmex 2 Cleared palp, ventral view. 3 Retrolateral view 4 Dorsal view 5 Ventral view, highlighting the path of spermaphore (yellow) and embolus (black) 6 Left palp, prolateral view 7 Right palp, prolateral view. Abbreviations: e’ = origin of embolus; e’’ = end of embolus; ma = median apophysis; s = spermophore; t = tegulum. Triangle marks base of median apophysis.

Figures 8–13. 

Male palps to show absence (8–10) or presence (11–13) of the cymbial apical groove (a depression in the cymbium that cradles the tip of the embolus, marked with an arrow) 8 Lyssomanes taczanowskii Galiano, 1980 9 Cocalodes papuanus Simon, 1900 10 Depreissia myrmex Lessert, 1942 11 Tomocyrba ubicki Szűts & Scharff, 2009 12 Hispo sulcata Wanless, 1981 13 Phidippus audax (Hentz, 1845). Triangle marks base of median apophysis (ma).

Many salticids outside of the Salticinae have a median apophysis on the palp, the loss of which is a synapomorphy of the Salticinae (Maddison and Needham 2006, Maddison et al. 2007, Maddison 2009, Maddison in press). The median apophysis arises from the tegulum, and is usually separated from it by a membrane (e.g., Maddison and Needham 2006, Maddison et al. 2007, Maddison 2009). On the tegulum of Depreissia is a large complex apophysis (Wesołowska 1997: fig. 3, Deeleman-Reinhold and Floren 2003: fig. 3), referred to as a tegular projection by Deeleman-Reinhold and Floren (2003). It arises from the middle of the face of the tegulum, expands to a bulbous projection, then narrows and twists at its heavily sclerotized tip (Figs 2–7, 10, ma). This projection is quite distinct from the tegulum, separated from it by a narrow waist (Figs 3, 6, 10, triangle), and is apparently surrounded by a membranous area (Figs 6, 7, 10, triangle). No tegular apophysis with these qualities is seen in salticids except the median apophysis of basal salticids. We therefore judge it to be a median apophysis, which places Depreissia outside the Salticinae.

Deeleman-Reinhold et al. (2016) also conclude that a median apophysis is present, but they interpret it to be a smaller sclerite. While we interpret the entire “tegular projection” to be the median apophysis, Deeleman-Reinhold et al. (2016) interpret the projection to be a lobe of the tegulum, and only the dark tip of the projection to be the median apophysis (“tip-only”). Our interpretation is based on the fact that the tegular projection is separated by a narrow and membranous neck from the rest of the tegulum, matching the quality of the tegulum-median apophysis boundary as seen in other salticids. We judge the “tip-only” interpretation as less parsimonious, because it implies a new distinct feature not seen in other salticids (an isolated ventral lobe of the tegulum) as well as a loss of the membrane at the base of the median apophysis.

Our interpretation suggests that the median apophysis is unusually large, but cocalodines have remarkably large median apophyses (Maddison 2009), which may indeed be a synapomorphy uniting Depreissia with the cocalodines. Except for Cucudeta gahavisuka Maddison, 2009, cocalodines have a median apophysis whose length is as great as or greater than half the diameter of the bulb (see figures in Maddison 2009). Lapsiines, spartaeines, and hisponines have smaller median apophyses, with the exception of Thrandina Maddison, 2006 (Maddison 2012); the size in lyssomanines is variable (see e.g. Logunov 2014).

Another character that clearly supports the non-salticine status of Depreissia is the lack of a depression in the cymbium cradling the tip of the embolus (see Figs 8–13). In hisponines and salticines, the tip of the embolus falls in a consistent place over the tip of the cymbium, resting in a shallow, elongated groove in the tegulum (Figs 11–13, arrow). Among salticids outside the hisponines and salticines, the groove is absent (Figs 8–9). It is also lacking in Depreissia (Figs 2–4, 7, 10). Outside the salticids it is lacking in the apparently closely-related crab spiders (Ramírez 2003, 2014), but it is present in anyphaenids (Ramírez 2003) and castianieirines (Ramírez 2014). This groove, which occasionally extends to the dorsal side, was called the cymbial groove by Szűts and Scharff (2005), and is one of several cymbial grooves of Ramírez (2014), the cymbial apical groove. The presence of a cymbial apical groove cradling the embolus is concordant with molecular evidence that supports the clade consisting of hisponines plus salticines (Maddison et al. 2014). Its absence is therefore evidence that Depreissia is a non-salticine.

While the morphological data support Depreissia as a non-salticine, the morphological data neither rule out its being a cocalodine, nor give good support for its placement with the cocalodines in particular. This is not surprising, as there are no known unambiguous morphological synapomorphies either for the cocalodines (Maddison 2009) or for the larger group including lapsiines and spartaeines.