Chrysilla Thorell, 1887

Deeleman-Reinhold, Christa L., Addink, Wouter & Miller, Jeremy A., 2024, The genera Chrysilla and Phintelloides revisited with the description of a new species (Araneae, Salticidae) using digital specimen DOIs and nanopublications, Biodiversity Data Journal 12, pp. e 129438-e 129438 : e129438-

Chrysilla Thorell, 1887

World Spider Catalog: urn:lsid:nmbe.ch:spidergen:02890

Chrysilla Thorell, 1887 - Thorell 1887

Chrysilla lauta Thorell, 1887 Thorell 1887: 378.

Description

Middle-sized (body length 3.2–7.2 mm) unidentate, sexually dimorphic spiders. Carapace profile sloping down directly behind the eyes in a straight line. Chelicerae in males simple, elongated and sometimes divergent, in females parallel. In males, leg I dark and longer than the others, other legs pale, in females all legs pale and leg I proportional; both sexes with some black rings on leg IV. Spination of legs: femur I-IV with 1-1 - 1 d, tibia I and II with 2-2 - 2 v or 2–2 - 2 - 1 v, metatarsus I and II with 2-2 v in both sexes; in C. lauta ventral spines on tibia I and II very strong, in other Chrysilla species front legs usually not so strongly armed. Abdomen in males about 1 ½ – 2 times longer than carapace, in female shorter and more rounded. The dorsal pattern is variable between species.

Diagnosis

Chrysilla can be distinguished from other chrysillines by the following set of characters: 1) – body colour: live specimens are conspicuously coloured in patterns of white, black, red, iridescent blue or green; in specimens kept in alcohol, the red colour rapidly disappears. Similar colours are also found in Siler Simon, 1889 ; 2) – clypeus: Chrysilla lauta Thorell, 1887 , C. volupe ( Karsch, 1879) , C. deelemani Prószyński & Deeleman-Reinhold, 2010 , and Proszynskia Kanesharatnam & Benjamin, 2019 lack a bunch of long white setae and have only dark metallic scales on the clypeus (in life), whereas a white bunch on the clypeus is characteristic for Phintelloides . However, the description of Chrysilla acerosa Wang & Zhang, 2012 is provided with numerous colour photos, one of which clearly shows bundles of white flattened setae in front of the AME; 3) – thorax margins: in Chrysill a and Siler semiglaucus , both sexes have the thorax sides lined by a narrow strip of iridescent scales ( Kanesharatnam and Benjamin 2019, fig. 21 A; Yamasaki et al. 2018, fig. 11), whereas Phintelloides and Phintella have a wide band of white flattened setae along the margin of the thorax in both sexes; 4) – abdomen: in all known Chrysilla species, males have a long, cylindrical abdomen, about three times longer than wide and clearly narrower than the carapace, sometimes with a dorsal scutum covered with colourful iridescent scales. In the field, the species can be recognized by their colour pattern. In females, the abdomen is notably shorter. By contrast, the male abdomen in Phintella and Phintelloides is shorter and more rounded, occasionally with something like a scutum; 5) – cymbium length: in Chrysilla and Phintelloides the slender palp has a long cymbium cap (cc) with parallel sides, measuring more than half the bulbus length. This contrasts with Phintella , which has a cc of less than half the bulbus length, and Siler , which has a short cc that protrudes only barely beyond the tip of the embolus; 6) – embolus: in Chrysilla the embolus proper (ep) is thin and filiform as in Phintelloides ; in Phintella and Proszynskia the ep is short and sclerotized, rigid and conical or acuminate, never filiform; in Siler the embolus is conical; 7) – embolar tegular branch (etb) is present in males of Chrysilla and in Phintelloides scandens and most probably also in the Phintelloides species from India and Sri Lanka; it is long, slender and flexible; the tegulum is like a fingerless glove with movable thumb; in Phintella , Proszynskia and Siler , the etb is absent, the embolus-bearing part not separate, the tegulum is rigid like a trowel 8) – tegular lobe (pl) and tegular bump: in Chrysilla and Phintelloides the lobe is broad and rounded (Fig. 1), or shallow as in P. scandens (Fig. 14 a , b , c , d , e ); in Phintella and Siler it is triangular / funnel-shaped; in Proszynkia it is expanded and broadly rounded; all species have a bump on the tegulum, traditionally present in all chrysillines, usually in the middle or in the proximal half of the tegulum; 9) – palpal colour: in Chrysilla , palp segments are contrasting, with different segments exhibiting different combinations of dark and white. The dark segments look iridescent blue or black in photos of live specimens; this seems to be a reliable character for species identification. In Phintella and Phintelloide s, palps are uniformly coloured, or all pale with dark cymbium; in Siler semiglaucus specimens, the femur, patella and tibia have various shades of buff or grey (in life probably blue or green), the cymbium is pure white as in Chrysilla ; 10) – epigynal structure: Chrysilla and Phintelloides have a similar structure, deviating from all related genera: the lateral copulatory opening is vaguely defined (except in C. deelemani ), the entrance section to the copulatory ducts is a large atrium, usually funnel-shaped like an opened birds beak, leading through a conspicuous, U-turn section with swollen parietal walls (bnc) (not swollen in C. deelemani and C. scandens ) in transition to the vertical section of the copulatory ducts (cd) which are tubular and rigid. In Phintella , the copulatory opening is normally marked with a rigid ring, usually but not always positioned anteriorly ( Kanesharatnam and Benjamin 2019: figs 33 F, 36 C). In Chrysilla , the middle, U-shaped section is often described as a birds’ neck (bnc), with a beak (atrium); spermathecae are situated near the posterior edge of the epigyne, they are round or reniform as in Phintella and relatively small; in Phintella the ducts are straight or curved and of various lengths; in Siler the copulatory opening is hidden in an anterior hood, the copulatory ducts are very short. The posterior epigynal margin is chitinized and provided with a pair of shallow pockets in most chrysilline genera.

Distribution

Seven Chrysilla species have been recorded from South and Southeast Asia with specimen records from the following countries: Sri Lanka, India, Pakistan, Nepal, Bhutan, Myanmar, Thailand, Vietnam, Malaysia, Singapore, Taiwan, Indonesia and southwest China. In addition, two species are recorded from tropical Africa, and one from Australia.

Taxon discussion

Chrysilla species are sexually dimorphic, and preserved specimens appear substantially different compared to living animals. This led to much confusion about the identity of the genus. It was more than a century after the first description of Chrysilla that males and females were associated ( Caleb et al. 2018, Wang and Zhang 2012). Live animals of the different sexes exhibit different patterns and colours in both carapace and abdomen (Fig. 2; Caleb et al. 2018, Koh et al. 2022, Wang and Zhang 2012). Ten species are currently catalogued ( World Spider Catalog 2024); with the description herein of the previously unknown female of C. deelemani Prószyński & Deeleman-Reinhold, 2010 , five Chrysilla species are known from only one sex. Chrysilla doriae Thorell, 1890 (male, Sumatra), has a palp which is typical for Phintella species and the species probably is a synonym (CDR personal observation of holotype). The holotype of Chrysilla delicata Thorell 1892 (female, Sumatra; not Myanmar, contra World Spider Catalog 2024) was very recognisably illustrated ( Prószyński 1984: 69), together with the palp of a syntopic male " Icius glaucochira Thorell, 1890 . " Later, the male Phintella conradi Prószyński and Deeleman-Reinhold 2012 was described from another (but likely conspecific) male specimen from Sumatra. Recently, Kanesharatnam and Benjamin (2019) established Chrysilla jesudasi Caleb & Mathai, 2014 as the type species of the new genus Phintelloides .

Chrysilla in many ways resembles and has been repeatedly confused with Phintella Strand, 1906 ( Żabka 1985). A series of phylogenetic analyses of chrysilline salticids found Phintella and Phintelloides to be closely related, possibly in a clade with Proszynskia and Icius ; Chrysilla is somewhat distantly related from these genera, and more closely related to Siler ( Kanesharatnam and Benjamin 2019) . Conflict within the Kanesharatnam and Benjamin (2019) study derives from analytical permutations of morphological and DNA sequence data under parsimony and likelihood optimality criteria. The absence of conspicuous bright colours makes species of Phintelloides look superficially like Phintella species. Nevertheless, the morphological and functional copulatory characters are substantially similar in Chrysilla and Phintelloides , and distinct from those in genera such as Phintella and Proszynskia .

Our diagnosis can be expressed in simple words: genus Chrysilla and Phintelloides share their reproductive engine (copulatory organs) but are enveloped in a different coat; black, white and yellow setae in Phintelloides , red body colour in life and iridescent scales with black and white in Chrysilla . Involving more chrysilline genera: the “ Chrysilla coat ” is more widespread and also is characteristic for other chrysilline genera, such as Siler , Cosmophasis and Orsima , whereas the specialised “ Chrysilla engine ” is shared between Chrysilla and Phintelloides , but remarkably is also present in the genus Bristowia , a genus Maddison (2015) provisionally placed in the Hasariini.

Figures

Figure 14 a. Phintelloides scandens sp. nov., male holotype, pedipalp, ventral view, RMNH. ARA. 18251, scale bar 0.2 mm

Figure 14 b. Phintelloides scandens sp. nov., male holotype, pedipalp, retrolateral view, RMNH. ARA. 18251, scale bar 0.2 mm

Figure 14 c. Phintelloides scandens sp. nov., male pedipalp, ventral view, illustration, scale bar 0.2 mm

Figure 14 d. Phintelloides scandens sp. nov., male pedipalp, retrolateral view, illustration, scale bar 0.2 mm

Figure 14 e. Phintelloides scandens sp. nov., male pedipalp, prolateral view, illustration, scale bar 0.2 mm