Tetragnatha guatemalensis O. Pickard-Cambridge, 1889

de Souza Castanheira, Pedro & Baptista, Renner Luiz Cerqueira, 2021, Redescription of Tetragnatha guatemalensis, T. laboriosa and T. jaculator, with new synonymies of genus Tetragnatha (Araneae: Tetragnathidae) in the Neotropical Region, Journal of Natural History 54 (47 - 48), pp. 3031-3057 : 3033-3040

Tetragnatha guatemalensis O. Pickard-Cambridge, 1889

( Figures 1–28 , 82 )

Type data

Tetragnatha guatemalensis O. Pickard-Cambridge, 1889: 8 , pl. 2, figs 6, 7 [1 male lectotype and 1 female paralectotype from Laguna de los Coheteros (near Coban), Cahabon, Guatemala, in NHM, Sarg & Champion leg., not examined] . F. O. Pickard-Cambridge 1903: 431, figs 12a–f, 13 (lectotype designation).

Tetragnatha parva Badcock, 1932: 14 (female holotype from Campo Grande , Paraguayan Chaco, Paraguay, in NHM, 02.IX.1926, examined) syn. nov.

Diagnosis

Males and females of T. guatemalensis are similar to T. ceylonica O. Pickard-Cambridge, 1869 and T. gracilis (Bryant, 1923) . Males share the following characters: ‘a’ median-sized and located in the middle line of paturon, presence of pointed ‘t’, small ‘T’, Gu absent; ‘sl’ short, placed away from the fang groove, not aligned to other teeth of the upper row but displaced to a position just below the fang; palps of both species with tibias with approximately same length, very long paracymbium, with slanted and pointed notch, extending well beyond the tip of the paracymbium proper, conductor with its apical third slanted in an almost right angle and its tip curved ( Figures 4–6, 8, 11 21, 22, 25, 27 ; Zhu et al. 2003, fig. 58A–C, E; Dimitrov et al. 2008, fig. 3B, D, E). Tetragnatha guatemalensis is set apart by ‘sl’ basalward projected (shared with T. ceylonica ), smaller ‘T’, rsu with 5–7 teeth (only two in T. gracilis ), conductor only wrapping around the embolus at the apical third (shared with T. ceylonica ), larger paracymbium with more elongated and finger-like notch ( Figures 4–6, 8, 11 , 21, 22, 25, 27 ; Zhu et al. 2003, fig. 58A–C, E; Dimitrov et al. 2008, fig. 3B, D, E). Females of T. guatemalensis share with T. ceylonica and T. gracilis small chelicerae, very short genital fold, two small ovoid or rounded spermathecae and one rounded CS ( Figures 12–19 ; Zhu et al. 2003, fig. 57C–E, G; Dimitrov et al. 2008, fig. 4A–C). However, T. guatemalensis can be easily distinguished by the absence of a swallow on the paturon (in comparison to T. ceylonica ), a smaller gap between Gl and L2, presence of OC on fang, ovoid spermathecae (rounded in T. gracilis ), and CS placed at the same level of the spermathecae (anteriorly placed at T. ceylonica ) ( Figures 16, 17, 20 , 23, 24 ; Zhu et al. 2003, fig. 57C–E, G; Dimitrov et al. 2008, fig. 4A–C).

Description

Male: Carapace yellowish brown and elongated, with a slightly elevated anterior part ( Figures 1, 2 ). Labium light brown and longer than wide ( Figure 3 ). Sternum oval, light brown, with dusky contour ( Figure 3 ). Eyes parallel and procurved, ringed in black and spaced apart, ALE and PLE almost touching ( Figure 1 ). Legs yellowish brown and very elongated, legs I and II slightly darker ( Figures 1–3 ). Chelicerae paturon yellowish brown, thick, approximately 3.8x longer than wide and almost as long as the carapace, moderately curved outwards, around 30° from the median line of the body ( Figures 1, 4–7 , 21, 22 ). ‘a’ short, thick, tubular, bending up and distalward, with a strong notch on its tip, and slightly displaced innerwards from the middle width of paturon ( Figures 4, 5 , 21 ). AXu absent ( Figures 4, 5 , 21 ). ‘t’ pointed and distalward projected ( Figures 4, 5 , 21 ). Upper row with eight uneven teeth ( Figures 4, 5 , 21 ): Gu absent; ‘sl’ thick, triangular and pointed, basalward projected, slightly displaced innerwards from the teeth row and placed just below the fang; ‘T’ thin, pointed, and very elongated, displaced outwards from the row of teeth itself; ‘rsu’ composed of six pointed teeth decreasing in size and apart by regular gaps. AXl reduced to a rounded nub ( Figures 5, 6 , 22 ). Lower row with nine teeth distalward projected, decreasing in size and apart by regular gaps, with Gl thicker and longer than others ( Figures 5, 6 , 22 ). Cheliceral fang as wide as its base, thick and uniformly tapering to its tip, closing on Gu, then curving to the middle line of both rows of teeth, a tiny hard to see outer cusp near fang basis ( Figures 4–6 , 21, 22 ). Abdomen cylindrical, slender, approximately 1.9x longer than the carapace, entirely pale beige, and covered by guanine crystals, with no lateral lines ( Figures 1–3 ). Epiandrous plate small, wider than long, with a thick median division and composed of six spigots on each portion ( Figure 28 ). Palps with an elongated cymbium, around 2x longer than the conical and not very elongated tibia ( Figures 8–10 , 25 ); tegulum spherical and slightly slanted, inflated and 1.9x wider than high ( Figures 8, 9 , 25 ); conductor elongated, double pleated, slanted and abruptly projected distalward on its last third, where it completely encloses the embolus and ends in a curved and rounded tip ( Figures 8–10 , 25, 26 ); embolus thick, filiform and slanted, ending in curved tip, its apical third completely enfolded by conductor ( Figures 8–10 , 25, 26 ); paracymbium extremely elongated, approximately 6.5 longer than wide, with reduced thin transparent lobe at median region of its outer border, a long knob dorsally curved and ending in a mesally constricted curved, finger-like, undivided notch ( Figures 11 , 27 ).

Total length 6.90. Carapace 2.36 long, 1.33 wide. Abdomen 4.48 long, 0.97 wide. Left chelicera 1.90 long, 0.56 wide. Leg formula I–II–IV–III. Leg I: femur 6.29, patella 0.72, tibia 6.19, metatarsus 7.12 and tarsus 1.49. Leg II: patella + tibia 4.29. Leg III: patella + tibia 1.75. Leg IV: patella + tibia 3.89.

Female: Carapace colour, endites, fovea, eyes, labium, sternum and legs as in male ( Figures 12–14 ). Chelicerae paturon with the same colour as male, around 3x longer than wide, 2x shorter than the carapace, and placed around 35° from the median line of the body. Paturon slightly bulges at the middle portion of the upper region ( Figures 12 15–18 , 23, 24 ). AXu absent ( Figures 15, 16 , 23 ). Upper row with seven teeth distalward projected ( Figures 15, 16 , 23 ): Gu finger-like, thick with a quite large basis, located near the fang groove and apart from U2 by a moderate gap; U2 sclerotised, pointed and distalward projected, with almost the same size as U3 and located midway between Gu and U3; U3– U7 decreasing in size and apart by small gaps. AXl extremely reduced to a small nub ( Figures 16, 17 , 24 ). Lower row with eight teeth distalward projected ( Figures 16, 17 , 24 ): Gl, L2 and L3 thicker and more sclerotised than L4–L8. Gl with a wider basis and apart from L2 by a moderate gap. L2–L8 apart by small gaps. Cheliceral fang short and very thick, closing between both rows of teeth, serrated from midway to its tip, and bearing a small, thick and not protruding outer cusp, slightly displaced to lower face of fang ( Figures 15–17 , 23, 24 ). Abdomen as in male, but much higher and wider, around 3x longer than the carapace, with a clear hump at the anterior third and ending in a small and wide rounded tip reaching further than the spinnerets ( Figures 12–14 ). Genital fold brown, not elongated, 5x wider than long, with a straight posterior rim ( Figure 19 ). Internal genitalia composed of two pairs of large oval spermathecae, the posterior one larger than the anterior, both connected midway to a wide uterus externus, and a sclerotised reddish central membranous sac atop of a small stalk ( Figure 20 ).

Total length 8.31. Carapace 2.15 long, 1.59 wide. Abdomen 6.34 long, 2.30 wide. Left chelicera 1.37 long, 0.48 wide. Leg formula I–IV–II–III. Leg I: femur 4.77, patella 0.94, tibia 4.73, metatarsus 5.30 and tarsus 1.92. Leg II: patella + tibia 3.35. Leg III: patella + tibia 1.45. Leg IV: patella + tibia 2.91.

Variation

Males (n = 6): total length, 6.23–8.44; females (n = 9): total length, 7.40–8.87. There is a small variation on the position and size of ‘a’. It may be placed almost at the middle line of the paturon or variably displaced innerwards. Also, its tip may be clearly carved or just with a small incision. ‘t’ may be small and triangular ( Figures 4, 5 ) or elongated and almost digitiform ( Figure 21 ). The position of ‘T’ varies moderately, from closer to ‘a’ and ‘sl’ ( Figure 4 ) to closer to ‘rsu’ ( Figure 21 ). The number of lower teeth after L2 varies from six to eight (eight to ten considering the entire row). In specimens with lower number of teeth, a large gap may appear between L2 and remaining teeth ( Figure 22 ). The OC in the male fang may be larger and quite perceptible, or almost disappears. The finger-like paracymbium notch may vary in length and sometimes have its tip clearly curved.

Synonymy and notes

Tetragnatha guatemalensis was described based on males and females from Cahabon, Guatemala, without illustrations and it was not available during our visit to NHM collections. Fortunately, we could be guided by the redescription of this species by F. O. Pickard- Cambridge (1903, p. 431, fig. 12a–, 13), which was accompanied by good and comprehensive illustrations of male and female chelicerae and male palp of the syntypes. He also designated one male as the lectotype (calling it ‘type’ and the female ‘gynetype’), against Levi (1981, p. 296) who probably overlooked Cambridge’s previous designation. The species was later redescribed or described anew (as a synonym) many times (e.g. Seeley, 1928; Gertsch and Mulaik 1936; Chickering 1957c, 1959, 1962), but the specimens used in Levi (1981) and Okuma (1992), under their redescriptions of T. guatemalensis , appear to be different from previous redescriptions and from our South American specimens, at least if we only consider the males. The palps seem very similar, with its conductor and embolus projecting upward and a finger-like notch on paracymbium. However, the chelicerae of male specimens illustrated in Levi (1981, fig. 52) and Okuma (1992, figs 9A, B) (and also from one specimen from Dominican Republic we examined) differ a lot from typical T. guatemalensis : ‘t’ is absent; ‘T’ is also absent, as there is no tooth much larger than the others, and the corresponding tooth (possibly U2) is close to Gu; and Gl and L2 have their bases overlapping. The examination of a large series of additional North and Central American specimens and also the types of the five previous synonyms of T. guatemalensis is needed in order to ascertain if those specimens belong to a different species or not.

Tetragnatha parva Badcock, 1932 was described based on a female specimen from Campo Grande, Paraguayan Chaco. Comparing the holotype ( NHM, examined) to T . guatemalensis specimens from the state of Mato Grosso do Sul, near Brazilian / Paraguayan border, we realised that both species perfectly match, as their chelicerae bear the same Gu, U 2 and U3, and also Gl, L 2 and L3, besides having the same short and flattened genital fold . Therefore , we consider T . parva to be a junior synonym of T. guatemalensis syn. nov.

Regarding cheliceral morphology, we consider the first teeth on the upper row of T. guatemalensis , T. ceylonica and T. gracilis as a ‘sl’, and not a Gu ( Figures 4, 5 , 21 ; Zhu et al. 2003, fig. 58A–C; Dimitrov et al. 2008, fig. 3D, E). Gu is a guide tooth, usually placed just aside the fang and directed forward. In these three species, the first upper tooth, called ‘sl’ here, is displaced away from the fang groove and towards the lower side, being placed under the fang and sometimes not visible in inner view ( Figure 5 ). Also, it is usually curved and downwards projected (except in T. gracilis ) and placed at a level similar to ‘a’. A similar position and shape of ‘sl’ may be found in other species with Gu and ‘T’, as in T. elongata , T. jaculator and T. laboriosa ( Figures 32, 33 , 48 , 59, 60 , 74 ; Castanheira et al. 2019, figs 5D, E, 7A). In T. jaculator , the ‘sl’ is also displaced and located under the fang ( Figures 59, 60 , 74 ), but not in T. elongata and T. laboriosa . It is more parcimonious to consider Gu as absent in T. guatemalensis , T. ceylonica and T. gracilis than a parallel evolution of ‘sl’ characteristics in all those species ( Figures 4, 5 , 21 , 32,33 , 48 , 59, 60 , 74 ; Zhu et al. 2003, fig. 58A–C; Dimitrov et al. 2008, fig. 3D,E).

Distribution

Besides the previous records for North America, Mexico, Guatemala, Cuba and Jamaica (see World Spider Catalog 2020), we now record this species from South America, with specimens from Paraguay and Brazil ( Figure 82 ).

Material examined

BRAZIL. Rondônia: Candeias do Jamari, Usina Hidrelétrica de Samuel, Rio Jamari (−8.809722, −63.695556), ♂, XII .1988, Eq . Butantan leg . ( IBSP 6691 ) ; Tocantins: Palmas (−10.184444, −48.333611), ♀, I .2002, D . M . Cândido & M . Costa leg . ( IBSP 240814 ex 40486); Serra do Lajeado (−10.2563882, −48.1022318), ♂, ♀, III .2003, G . Puorto leg . ( IBSP 224613 ) ; Mato Grosso do Sul: Jaraguari, Furnas de Dionísio (−20.141944, −54.398889), ♀, 14 . XI .2015, D . Araújo leg . ( IBSP 167046 ); Santa Rita do Rio Pardo (−21.302778, −52.830833), ♀, 27 .IV .2001, R . Bertani & E . K. Kashimata leg . ( IBSP 235086 ex 39482); Anaurilândia (−22.187778, −52.717778), ♂, 05–11 .III .2001, F . S . Cunha & J . P. L. Guadanucci leg . ( IBSP 240809 ex 39358); Usina Hidrelétrica Engenheiro Sérgio Motta (−22.4783686, −52.9625009), 4♀, 12–19 .III .2001, F . S . Cunha & C . A. R. Souza leg . ( IBSP 239868 ex 39500); Parque Nacional de Ilha Grande (−23.6912697, −53.9901574), ♀, 12 .VIII .1963, M . P . Bueno leg . ( IBSP 240807 ex 2685) ; São Paulo: São Paulo, Reservatório Guarapiranga, Parque Ilha dos Eucaliptos (−23.550278, −46.633889), ♀, 07–13 .X .2003, I . Cizauskas & C . R. M. Garcia leg . ( IBSP 61343 ); Mogi das Cruzes, Manoel Ferreira , Biritiba- UÇu (−23.522778, −46.187778), 8♂, 12♀, V .2001, E . K . Kashimata & R . Martins leg . ( IBSP 235083 ex 56320) ; Santa Catarina: Florianópolis, Parque Municipal Lagoa do Peri (−27.596944, −48.548889), ♂, ♀, 29 .VIII .2014, R . P . Indicatti, R. Y. Lemos, J. L. Chavari leg . ( IBSP 214202 ) ; Rio Grande do Sul: Tapes (−30.672778, −51.395833), ♂, 1992, R . L . Oliveira Júnior leg . ( MCTP 6267 ) .

Figures

Figure 82. New records of T. guatemalensis, T. laboriosa and T. jaculator in the Neotropical Region.

Figures 1–11. Tetragnatha guatemalensis male: 1, dorsal habitus (IBSP 224613); 2, lateral habitus (IBSP 224613); 3, ventral habitus (IBSP 224613); 4, left chelicera, upper view (IBSP 224613); 5, left chelicera, inner view (IBSP 224,613); 6, left chelicera, lower view (IBSP 224613); 7, left chelicera, outer view (IBSP 224613); 8, left palp, mesal view (MCTP 6267); 9, left palp, mesal view (bulb detail); 10, left palp, dorsal view (MCTP 6267); 11, left palp, ventral view (paracymbium) (MCTP 6267). Scale bars: Figures 1–3, 2 mm; Figures 4–8, 0.5 mm; Figures 9–11, 0.2 mm.

Figures 12–20. Tetragnatha guatemalensis female: 12, dorsal habitus (IBSP 224613); 13, lateral habitus (IBSP 224613); 14, ventral habitus (IBSP 224613); 15, left chelicera, upper view (IBSP 224613); 16, left chelicera,inner view (IBSP 224613); 17, left chelicera, lower view (IBSP 224613);18, left chelicera, outer view (IBSP 224613); 19, genital fold, ventral view (IBSP 224613); 20, internal genitalia, ventral view (IBSP 235083 ex 56320). Scale bars: Figures 12–14, 2 mm; Figures 15–19, 0.5 mm; Figure 20, 0.2 mm.

Figures 21–28. Tetragnatha guatemalensis SEM photos (IBSP 235083 ex 56320), male: 21, left chelicera, upper view; 22, left chelicera lower view; 25, left palp, mesal view; 26, conductor and embolus opening, dorsal view; 27, paracymbium, ventral view; 28, epiandrous, ventral view. Female: 23, left chelicera, upper view; 24, left chelicera, lower view. Scale bars: Figures 21–24, 0.5 mm; Figure 25, 0.2 mm; Figures 26, 28, 0.02 mm; Figure 27, 0.1 mm.

Figures 29–38. Tetragnatha laboriosa male (MACN 24651): 29, dorsal habitus; 30, lateral habitus; 31, ventral habitus; 32, left chelicera, upper view; 33, left chelicera, inner view; 34, left chelicera, lower view; 35, left chelicera, outer view; 36, left palp, mesal view; 37, left palp, dorsal view; 38, left palp, ventral view (paracymbium). Scale bars: Figures 29–31, 2 mm; Figures 32–38, 0.5 mm.

Figures 48–55. Tetragnatha laboriosa SEM photos, male: 48, left chelicera, upper view (MACN 24651); 49, left chelicera lower view (MACN 1184); 52, left palp, mesal view (MACN 24651); 53, conductor and embolus opening, mesal view (MACN 24651); 54, paracymbium, ventral view (MACN 24651); 55, epiandrous, ventral view (MACN 1184). Female: 50, left chelicera, upper view (MACN 24651); 51, left chelicera, lower view (MACN 1184). Scale bars: Figures 48–51, 0.2 mm; Figure 52, 0.1 mm; Figures 53, 55, 0.02 mm; Figure 54, 0.05 mm.

Figures 56–65. Tetragnatha jaculator male (UFRJ 1621): 56, dorsal habitus; 57, lateral habitus; 58, ventral habitus; 59, left chelicera, upper view; 60, left chelicera, inner view; 61, left chelicera, lower view; 62, left chelicera, outer view; 63, left palp, mesal view; 64, left palp, dorsal view; 65, left palp, ventral view (paracymbium). Scale bars: Figures 56–58, 2 mm; Figures 59–65, 0.5 mm.

Figures 74–81. Tetragnatha jaculator SEM photos, male: 74, left chelicera, upper view (MCTP 43314 ex 5987); 75, left chelicera lower view (MCTP 7887); 78, left palp, mesal view (MCTP 7887); 79, conductor detail, mesal view (MCTP 7887); 80, paracymbium, ventral view (MCTP 7887); 81, epiandrous, ventral view (MCTP 7887). Female (MCTP 7887): 76, left chelicera, upper view; 77, left chelicera, lower view. Scale bars: Figures 74–77, 79, 80, 0.2 mm; Figure 78, 0.5 mm; Figure 81, 0.05 mm.