Tetragnatha renatoi, Castanheira & Baptista, 2020

Castanheira, Pedro De Souza & Baptista, Renner Luiz Cerqueira, 2020, Notes on slender species of the long-jawed spider genus Tetragnatha (Araneae Tetragnathidae) with description of three new species, Zootaxa 4768 (1), pp. 43-75 : 51-56

Tetragnatha renatoi new species

( Figs 4–6 ; Map 1)

Type-material. Holotype ♂. BRAZIL, Rio Grande do Sul: Viamão : 24.III.1995, A. A. Lise et al. leg. ( MCTP 43329 ex 5944) . Paratypes: ARGENTINA, Misiones: Parque Nacional Iguazú , 23–26.X.1995, M. Ramírez leg., 1 ♂, 1 ♀ ( MACN 24546 ) ; BRAZIL, Paraná: Rio Negro : Franciscanos leg., 1 ♂ ( MNRJ 14148 ) ; Rio Grande do Sul: Viamão: Est. Exp. Fitotécnica , 12.VIII.1994, A. A. Lise et al. leg., 1 ♂ ( MCTP 5261 ); 24.III.1995, A. A. Lise et al. leg., 1 ♂ ( MCTP 43330 ex 5944); 10.X.1995, A. A. Lise et al. leg., 1 ♂ ( MCTP 6816 ); 17.X.1995, A. A. Lise et al. leg., 1 ♂ ( MCTP 8090 ); 07.XI.1995, A. A. Lise et al. leg., 1 ♂, 1 ♀ ( MCTP 43331 ex 7807); 15.XII.1995, 1 ♂ ( MCTP 8802 ) ; Rondônia: Porto Velho : 15.IV.1996, Equipe IBSP leg., 1 ♂ ( IBSP 16123 ) ; São Paulo: São Paulo: Parque Ilha dos Eucaliptos, Jardim Ângela, Reservatório de Guarapiranga , 09–15.IX.1999, pitfall traps, R. P. Indicatti et al. leg., 1 ♂ ( IBSP 132295 ); 07–13.X.2003, I. Cizauskas & C. R. M. Garcia leg., 2 ♂ ( IBSP 61387 ); VEN- EZUELA, Lara: Parque Nacional Yacambú, XII.2002, A. P. González & A. Giupponi leg., 1 ♂ ( MNRJ 60020 ) .

Additional material examined. BRAZIL, Paraná: Pinhais: Serra da Farinha Seca , 15–20.XI.1995, A. A. Lise et al. leg., 1 ♂ ( MCTP 7602 ) ; Pernambuco: Araçoiba: Centro de Instrução Marechal Newton Cavalcanti , 24.II.2011, C. A. Rheims & A. A. Costa Silva Filho leg., 1 ♂ ( IBSP 170200 ) ; Rio Grande do Sul: Campo Bom: 19.X.1987, C. J. Becker leg., 1 ♂ ( MCTP 43326 ex 0124); Novos Cabrais: Parque Witeck , 09.X.2008, R. G. Buss leg., 1 ♂ ( MCTP 28044 ); Santa Maria : 18.II.1999, C. B. Kotzian & L. Indrusiak leg., 1 ♂ ( MCTP 43328 ex 40657) ; Santa Catarina: Rio Uruguai , IX.2010, J. Cabra leg., 1 ♂ ( MCTP 43327 ex 34356) .

Etymology. The specific epithet is a noun given in honor to Renato A. Teixeira, curator of MCTP, where most of the specimens are deposited, and who graciously loaned countless material for the present and other research projects.

Diagnosis. Regarding to body morphology, males of Tetragnatha renatoi new species are similar to all species herein described (see diagnosis T. megalocera new species above). Unlike them, T. renatoi new species lacks the lateral black patches on the abdomen ( Fig. 4A ). Male chelicerae are more similar to T. gertschi Chickering, 1957 , insofar as both species have small sized chelicerae, similar row of upper teeth, where U2 and U3 are the most elongated teeth and have similar size, and fang with small inner cusp ( Figs 4A, B , 6A ; Chickering 1957c, fig. 42; Okuma 1992, fig. 8A, B). The two species’ chelicerae are set apart by the following differences in T. renatoi new species: carved ‘a’, placed nearest to the outer border, Gu very reduced, as a small nub near the basis of fang, presence of very reduced AXu (only visible at SEM photo), U2 clearly displaced upwards from the row itself, AXl reduced to a small tubercle (only visible in SEM photos), thick Gl apart from L2 by a moderate gap, L2 thick and slightly basalward projected and small L3 slightly displaced downwards from the row itself ( Figs 4 C–F, 6A, B; Chickering 1957c, fig. 42; Okuma 1992, fig. 8A, B)

On the other hand, females of T. renatoi new species have a more similar morphology to T. laboriosa Hentz, 1850 and T. vermiformis . The three species have a bulkier, not very elongated and slender body, usually with a wrinkled abdominal lateral border, chelicerae with a short paturon, without AXu or AXl and with moderate gaps between Gu–U2 and Gl–L2, and short genital folds ( Fig. 5 A–F, H; Levi 1981, figs 120, 121, 123; Okuma 1983, fig. 5D, E, J, K; Zhu & Zhang 2011, fig. 133C–G; Castanheira et al. 2019, figs 18A–H, 19B). However, T. renatoi new species can be set apart by the following set of characters: upper row of chelicerae with much bigger gap between U2 and U3, L2 shorter than Gl and slightly displaced from the lower row itself, genital fold with pointed posterior rim and internal genitalia bearing two massive spermathecae and a perfectly rounded central membranous sac ( Figs 5 D–F, H, I).

Description. Male (Holotype MCTP 43329): Carapace light yellowish brown, lighter on edges, elongated, flat, with no patches or lines, tapering toward the slightly elevated anterior rim ( Fig. 4A ). Fovea small with same colour of carapace ( Fig. 4A ). Labium brown and subquadrate ( Fig. 4B ). Sternum light brown with darker contour, concave near labium ( Fig. 4B ). Posterior eyes evenly separate, AME centrally placed and apart, ALE the smallest and located on the edge of carapace, PME and PLE with a moderate gap, PME and PLE almost touching ( Fig. 4A ). Legs light yellowish brown with spines on femur ( Fig. 4A, B ). Paturon approximately 2.5x longer than wide and about 70% as long as carapace, slightly curved outwards, around 50° from median line of the body, rounded with a straight apex ( Figs 4C, E ; 6A, B ). ‘a’ thin, slanted, with a distalward projected excavated tip ( Figs 4C, E , 6A, B ). AXu very reduced ( Fig. 6A ). Upper row with seven teeth ( Figs 4C, D , 6A ): Gu reduced to a thick nub near the basis of fang; ‘sl’ absent; U2 thick, sclerotized, slightly pointed distal- and upward and apart from Gu by a significant gap located on a bulge; U3–U7 pointed, straight and decreasing in size, with U7 reduced.AXl reduced to a small tubercle ( Fig. 6B ). Lower row with five normal teeth and another two seemingly vestigial ( Figs 4D, E , 6B ): Gl thick, conical, pointed, with large basis and distalward projected, L2 thick, with its tip slightly pointed and basalward projected, connected to the basis of fang by a small keel, L3 straight, small and pointed, basally apart from the row, L4 straight, pointed and longer than other teeth of the lower row, L5 with almost the same size as L3 but thinner and more pointed, L6–L7 vestigial. Cheliceral fang with almost the same width throughout, bearing an inner cusp on its first third and closing between rows of teeth ( Figs 4 C–E, 6A, B). Abdomen long, cylindrical and slender, around 2.3x longer than carapace ( Fig. 4A, B ). Dorsum pale beige, completely covered by guanine spots ( Fig. 4A ). Venter a little darker than dorsum, with some guanine spots placed in line near the border, starting below the lungs ( Fig. 4B ). Epiandrous wide with a large keel-shaped division midway, with nine fusules on the right side and five fusules on the left side ( Fig. 6G ). Palps with median sized tibia and cymbium, with almost the same size ( Figs 4 G–I, 6C); tegulum roundish, approximately 25% wider than high, bearing two parallel lines, forming a darker area in the middle ( Figs 4G , 6C ); conductor twisted, with thick edges enfolding over the embolus as a wide and projected pouch on its last portion ( Figs 4 G–I, 6C–E); embolus thick, slanted and filiform, originating at the middle portion of the bulb, with a small and slightly bending tip, hidden by the conductor all the way ( Figs 4 G–I, 6C–E); paracymbium subquadrate, with a bulky notch, translucid lobe very wide, occupying 2/3 of the paracymbium area ending near the notch and knob small, slightly bulging and basalward projected ( Figs 4I , 6F ).

Total length 7.25. Carapace 2.19 long, 1.29 wide. Abdomen 5.02 long, 0.89 wide. Left chelicera 1.53 long, 0.60 wide. Leg formula I–II–IV–III. Leg I: femur 6.92, patella 0.96, tibia 7.91, metatarsus 6.91 and tarsus 1.56. Leg II: patella + tibia 4.95. Leg III: patella + tibia 1.75. Leg IV: patella + tibia 4.40.

Female (paratype MCTP 43331): Carapace dark yellowish brown ( Fig. 5A ). Fovea rounded and pronounced, a little darker than carapace ( Fig. 5A ). Labium brown and elongated ( Fig. 5C ). Sternum with same colour as carapace, basally with two guanine spots ( Fig. 5A ). Eyes as in male ( Fig. 5A ). Legs light yellow with just few setae ( Fig. 5 A–C). Paturon approximately 2.9x longer than wide and about 75% as long as the carapace, retrolaterally straight, and around 55° from median line of the body ( Fig. 5 D–G). AXu absent ( Fig. 5D, E ). Upper row with eight teeth ( Fig. 5D, E ): Gu bulky, elongated, pointed, very sclerotized and distalward projected; U2 small, triangular and straight, located exactly midway between Gu and U3, which is elongated, pointed but not as bulky as Gu; U4–U8 pointed and decreasing in size. AXl absent ( Fig. 5E, F ). lower row with eight teeth ( Fig. 5E, F ): Gl similar to Gu, also bulky, elongated, pointed, very sclerotized and distalward projected; L2 pointed and slightly distalward projected, displaced from the row itself and located near the base of L3 after a deep furrow from Gl; L3 pointed, longer than L2, and with a distalward projected tip; L4 wide, pointed and a bit longer than Gl or any other teeth; L5–L8 pointed and decreasing in size. Cheliceral fang without projections, uniformly tapering and closing between both rows of teeth ( Fig. 5 D–F). Abdomen beige, not as elongated as in male, laterally wrinkled, around 2x longer than the carapace and dorsally covered by guanine spots ( Fig. 5 A–C). Genital fold elevated, approximately 3.5x wider than long, with a rounded and pointed tip on posterior rim ( Fig. 5H ). Internal genitalia composed of two massive, large and wide spermathecae and a perfectly rounded central membranous sac, located atop of a short neck ( Fig. 5I ).

Total length 6.51. Carapace 2.38 long, 1.14 wide. Abdomen 4.39 long, 1.36 wide. Left chelicera 1.24 long, 0.40 wide. Leg formula I–II–IV–III. Leg I: femur 5.95, patella 0.93, tibia 6.40, metatarsus 6.60 and tarsus 1.56. Leg II: patella + tibia 3.90. Leg III: patella + tibia 1.60. Leg IV: patella + tibia 3.83.

Variation. Males (n = 7): total length, 6.63 – 7.99. The lower row of teeth of the chelicerae of males can bear eight teeth instead of seven, with L7–L8 small but not vestigial, as observed on the SEM figure ( Fig. 6B ).

Notes. We considered the second tooth of the upper row as U2 on males, following Castanheira et al. ’s (2019) system. However, it could also be considered as a tooth similar to the “T” of T. tenuissima and the other two new species herein described, but just a little more robust than U3. Unfortunately, the homology between the cheliceral teeth is still debatable and will only be truly assessed in a phylogenetical analysis (see the “Structures of chelicerae” section above).

Natural History. Unknown.

Distribution. From Venezuela to Argentina. In Brazil, most specimens are so far known from Southeast and South regions, with one record for the Northeast (Pernambuco) and one for North (Rondônia) regions (Map 1).

MAP 1. Distribution of T. renatoi new species.

Figures

FIGURE 4. Tetragnatha renatoi new species male holotype: A, dorsal habitus. B, ventral habitus. C–F, left chelicera; C, upper view. D, inner view. E, lower view. F, outer view. G–I, left palp; G, mesal view. H, dorsal view. I, ventral view (paracymbium). Scale bars, A, B, 2 mm; C, D, E, F, 0.5 mm; G, H, I, 0.2 mm.

FIGURE 5. Tetragnatha renatoi new species female paratype (MCTP 43331): A, dorsal habitus. B, lateral habitus. C, ventral habitus. D–G, left chelicera; D, upper view. E, inner view. F, lower view. G, outer view. H–I, female genitalia; H, genital fold, ventral view. I, internal genitalia, dorsal view. Scale bars, A, B, C, 2 mm; D, E, F, G, H, 0.2 mm; I, 0.1 mm.

FIGURE 6. Tetragnatha renatoi new species SEM photos: A–B, male left chelicerae; A, upper view (MCTP 28044). B, lower view (MACN 24546). C–F, left male palp; C, mesal view (MCTP 28044). D, embolus detail, dorsal view (MCTP 43328 ex 40657). E, embolus detail, ventral view (MCTP 28044). F, paracymbium detail, ventral view (MCTP 28044). G, epiandrous detail, ventral view (MCTP 28044). Scale bars, A, B, 0.2 mm; C, D, F, 0.1 mm; E, 0.05 mm; G, 0.02 mm.