Phylogenetic analysis and revision of the linyphiid spider genus Solenysa (Araneae: Linyphiidae: Erigoninae) Author Tu, Lihong Author Hormiga, Gustavo text Zoological Journal of the Linnean Society 2011 2011-02-24 161 3 484 530 http://dx.doi.org/10.1111/j.1096-3642.2010.00640.x journal article 10.1111/j.1096-3642.2010.00640.x 0024-4082 5494095 SOLENYSA SIMON, 1894 Solenysa Simon, 1894: 677 . Type species: Solenysa melloteei Simon, 1894 . Composition: Twelve species, including five new species described here: Solenysa akihisai Tu sp. nov. , Solenysa geumoensis Seo, 1996 , Solenysa lanyuensis Tu sp. nov. , Solenysa longqiensis Li & Song, 1992 , Solenysa melloteei Simon, 1894 , Solenysa partibilis Tu et al ., 2007 , Solenysa protrudens Gao et al ., 1993 , Solenysa reflexilis Tu et al ., 2007 , Solenysa retractilis Tu sp. nov. , Solenysa tianmushana Tu sp. nov. , Solenysa wulingensis Li & Song, 1992 , and Solenysa yangmingshana Tu sp. nov. Diagnosis: Solenysa species can be distinguished from all other linyphiids by the four lateral lobes on each side of the carapace and by the tubular-shaped petiole ( Fig. 16A–C ). Males are also diagnosed by the palpal cymbium, which has a large probasal process and a small retrolateral process that is articulated with the paracymbium ( Fig. 12A ). Females are also diagnosed by the long membranous solenoid, which connects the epigynum to the abdomen, twists and lifts the epigynum up in nonfunctional stage ( Figs 8H , 13A ; see also Tu & Li, 2006b : figs 28–30). Description: Small spiders, male total length 1.11– 1.61, female 1.27–1.90. Both sexes similar in general appearance with little interspecies variation ( Fig. 16A–C ): cephalic region of both sexes turret-like, raised bearing AMEs in front, PMEs on top, ALEs and PLEs on its sides; AMEs black and very small, AMEd about half of other eyes, rest of eyes subequal; AER recurved, AME-AME less than AMEd, AME-ALE longer, PER straight, PME-PME equal to PMEd, PME-PLE shorter, ALE and PLE juxtaposed. Many impressed, round pits scattered on carapace and anterolateral surface of chelicerae ( Fig. 18B ). Posterior part of carapace elongated into a tubular-shaped petiole. Sternum continuous with carapace laterally, leaving four openings at each side through which coxae are articulated. In dorsal view four lobes can be distinguished around the leg coxae ( Fig. 16A–C ), but not conspicuous in S. longqiensis ( Fig. 14A ) and S. yangmingshana sp. nov. Legs long and slender, without macrosetae. Patella I–IV with one distal short spine ( Fig. 16B ). Tm I 0.17–0.26. Tm IV absent. Female palpal claw absent ( Figs 14E , 16D ). Book lung cover almost smooth ( Fig. 12G ). Epiandrous fusules absent in males (studied in S. partibilis , Fig. 12H; S . longqiensis, Fig. 15H; S . protrudens, Fig. 17E; S . retractilis and S. wulingensis , Fig. 20E ). Tracheal system consisting of unbranched median and lateral trunks; median pair slightly wider in diameter than lateral pair, extending into prosoma through petiole (studied in S. partibilis ; S. akihisai ; S. longqiensis ; S. protrudens , Fig. 16A; S . retractilis, Fig. 18C; S . wulingensis, Fig. 20A ). Spinnerets (studied in S. partibilis ; S. longqiensis ; S. protrudens ; S. retractilis ; and S. wulingensis ): ALS with one major ampullate gland spigot and one nubbin, as well as about 12 piriform gland spigots ( Fig. 16E ); PMS with one minor ampullate gland spigot ( Fig. 16G ), cylindrical gland spigot present ( Fig. 20G ) or not ( Fig. 16G ); PLS with four aciniform gland spigots between the two cylindrical gland spigots ( Fig. 16F ); basal part of mesal cylindrical gland spigot slightly larger than distal one ( Fig. 16F ); flagelliform and aggregate gland spigots (‘araneoid triplet’) well developed in females ( Fig. 16F ), reduced to nubbins in adult males ( Fig. 16H ), but present in adult males of S. retractilis ( Fig. 18F ) and S. wulingensis ( Fig. 20F ). Male palpal tibia with one prolateral, two retrolateral trichobothria ( Fig. 21A ). Proximal part of cymbium extending posteriorly and then turning retrolaterally, forming a large excavation and probasal process, protruding out ( Fig. 15A–C ), or hidden ( Fig. 21A ). Small retrolateral process anterior to proximal part of paracymbium ( Fig. 12A ). Paracymbium U-shaped, curved almost horizontally ( Fig. 15B ) or torsion-shaped turning in the middle ( Fig. 21A ) with additional curve at proximal part that articulates with cymbial retrolateral process ( Fig. 21A ). Tegulum with a chitinized triangular structure in retrolateral view, termed here as ‘S olenysa tegular triangle’ ( Fig. 16A ). Distal suprategular apophysis large, extending ventrally in retrolateral view ( Fig. 19A ). Radix usually small, combined with other elements of embolic division ( Fig. 15D ) or even embedded in a large membranous area that connects the basal part of terminal apophysis and lamella characteristica ( Figs 10D , 19E ). Terminal apophysis with three free ends, normally the median one larger ( Fig. 7 ). Lamella characteristica deeply divided into three well-developed branches, at least one of them, usually the median branch, ribbon like ( Fig. 7 ). Embolus short, sclerotized ( Fig. 12F ), translucent (less sclerotized) or totally membranous ( Fig. 19E, F ), without pointed embolus proper. No embolic membrane arising from column, but sometimes embolus with membranous projection, the distal embolar membrane (‘M’, see Figs 15F , 17D ). Epigynum well sclerotized, encapsulated, hanging at distal end of a long, transversally wrinkled, membranous solenoid ( Fig. 13A ). Solenoid arising from abdomen tegument, twisting and lifting epigynum up in nonfunctional stage ( Figs 8H , 13A ; see also Tu & Li, 2006b : figs 28–30). A pair of seams on epigynal dorsal surface; curved ( Fig. 13B ) or straight ( Fig. 14H ), transversal ( Fig. 17G ) or longitudinal ( Fig. 14H ); distal ends served as copulatory openings, proximal ends as fertilization openings. Fertilization ducts directed mesally ( Fig. 8I ). Remarks: The somatic morphology of Solenysa is quite uniform across species and shows little sexual dimorphism, although some of these features can be found in other linyphiids. For example, various types of cephalic lobes can be found in the males of other erigonine lineages (see Hormiga, 2000 : figs 32–35), whereas in Solenysa the cephalic lobe is found in both sexes. The round pits on the carapace and chelicerae of Solenysa are also present in several not closely related taxa [e.g. in Lophomma punctatum (Blackwall) , see Hormiga, 2000 : plate 47], but those of Solenysa have a flat bottom, and no seta arises from it ( Fig. 18B ). The tubular-shaped carapace petiole Figure 7. Morphology of the embolic division of Solenysa species. A –E, left, ventral; F, right, dorsal. A, Solenysa longqiensis ; B, Solenysa melloteei ; C, Solenysa lanyuensis sp. nov. ; D, Solenysa tianmushana sp. nov. ; E, Solenysa wulingensis ; F, Solenysa geumoensis . Abbreviations: ARP, anterior radical process; ATA, anterior terminal apophysis; DSA, distal suprategular apophysis; E, embolus; LC 1 , anterior branch of lamella characteristica; LC 2 , median branch of lamella characteristica; LC 3 , posterior branch of lamella characteristica; MTA, median terminal apophysis; PTA, posterior terminal apophysis; R, radix. Scale bars = 0.1 mm. · also can be found in Cresmatoneta mutinensis (Canestrini, 1868) . The simultaneous presence of these and other somatic characters is unique to Solenysa , which makes this genus easily distinguishable from all other linyphiids. In contrast to other erigonines, the radix in Solenysa is very reduced, to the extent that often it is not easy to distinguish it, and it is either combined with the terminal apophysis ( Fig. 15D ), or it becomes embedded in the membranous area which connects the basal part of the well-developed terminal apophysis and lamella characteristica ( Fig. 19E ). In the latter case, observed under the compound microscope, the radix is only a small, chitinized structure in the translucent area between the terminal apophysis and the lamella characteristica ( Fig. 10D ). Although this is not discernable in SEM images, it can be dissected out for examination. In fact, in one of our previous studies ( Tu & Li, 2006b ), we had totally missed the radix and incorrectly homologized the forward extending anterior branch of the lamella characteristica as the radix ( Tu & Li, 2006b : figs 8, 27, 46). Here we have corrected this mistake and have relabelled each structure with its correct morphological term ( Fig. 7 ). Consequently, the structure labelled as ‘R’ in Tu & Li (2006b : fig. 8, 18, 27, 46) is relabelled here as LC 1 ; ‘ LC 1 ’ and ‘ LC 3 ’ in Tu & Li (2006b : figs 8, 18, 27, 46) are relabelled here as LC 3 and posterior terminal apophysis, respectively. We document the presence of internal abdominal structures that we have interpreted to be of glandular nature (‘special glands’; see Fig. 20A, E ). These structures, visible after enzymatic digestion of abdominal tissues, can be found in a pair of clusters at or near the base of the PLS. We found these structures in females of S. longqiensis and in males of S. wulingensis . Phylogenetics: Solenysa falls within the ‘distal erigonines’ clade and its monophyly is unambiguously supported by numerous putative synapomorphies (see Discussion). The 12 Solenysa species are grouped into four clades ( Figs 5 , 6 ): the S. melloteei , S. longqiensis , S. protrudens , and S. wulingensis groups, each with a distinct genitalic pattern. Natural history: Solenysa species build small webs at base of grasses, above ground. They also can be found in leaf-litter by sifting. Distribution: The distribution of Solenysa species shows conspicuous regionality ( Fig. 22 ). To date, all Solenysa species have been recorded from 22.70°– 37.74°N , 102.70°– 139.30°E . The S. wulingensis clade includes four species distributed in the south-east of the mainland of China and Korea Peninsula; the S. melloteei clade includes four species only found in Japan ; the S. longqiensis clade and the S. protrudens clade, each including two species, are distributed on both sides of the Taiwan Channel. Every species is limited to its type locality and the adjacent area; none of them is widely distributed, but this could very well be the result of insufficient sampling.