Tetragnatha chauliodus ( Thorell, 1890 ),

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: 59-65

publication ID

http://doi.org/ 10.11646/zootaxa.4768.1.4

publication LSID

lsid:zoobank.org:pub:urn:lsid:zoobank.org:pub:7D766650-C568-433F-B087-D7EF7BEB1523

DOI

http://doi.org/10.5281/zenodo.3795480

persistent identifier

http://treatment.plazi.org/id/390B87EA-FF98-FF90-FF5A-AB35FC4BFD21

treatment provided by

Plazi

scientific name

Tetragnatha chauliodus ( Thorell, 1890 )
status

 

Tetragnatha chauliodus ( Thorell, 1890) 

( Figs 9–11View FIGURE 9View FIGURE 10View FIGURE 11; Map 2)

Limoxera chauliodus Thorell, 1890: 292  (♂, ♀).

Tetragnatha chauliodus: Gravely, 1921: 425  .

T. chauliodus: Okuma, 1987: 62  , fig. 15A–E (♀)

T. chauliodus: Okuma, 1988b: 196  , fig. 11A–L (♂, ♀, misidentified, = T. chiyokoae  new species)

T. chauliodus: Tanikawa, 1990: 9  , figs. 1–9 (♂, ♀, misidentified, = T. chiyokoae  new species)

T. chauliodus: Okuma et al., 1993: 44  , fig. 40A–G (♂, ♀, misidentified, = T. chiyokoae  new species)

T. chauliodus: Song et al., 1999: 221  , figs. 126A, G, W, X, 127A, B (♂, ♀, misidentified, = T. chiyokoae  new species) T. chauliodus: Zhu et al., 2003: 128  , figs. 59A–G, 60A–G (♀, but ♂ misidentified, = T. chiyokoae  new species)

Tetragnatha zhangfu Zhu et al., 2003: 197  , fig. 107A–H (♂) new synonymy

T. chauliodus: Tanikawa, 2007: 108  , figs. 401, 402, 865–867 (misidentified, = T. chiyokoae  new species)

T. chauliodus: Tanikawa, 2009: 416  , figs. 107–109 (misidentified, = T. chiyokoae  new species)

T. chauliodus: Basu & Raychaudhuri, 2016: 219  , fig. 6–10, 40–44 (♀, misidentified, = T. bogotensis Keyserling, 1865  )

Type material. Tetragnatha chauliodus  : SINGAPORE: ♂ lectotype and ♀ paralectotype herein designated (Coll. Cel. Workman) ( NHRS: GULI000070711), examined (photos)  ; MALAYSIA: ♀ paralectotype, Penang [Pinang] (Coll. Cel. Workman), not examined. Tetragnatha zhangfu    : CHINA: ♂ holotype, 1♂ and 2 immatures paratypes, Menglun [or Menglong] county (21°054’N, 101°12’E), Yunnan Province (Coll. Zhang Chao, 24.VI.2001), examined (photos)GoogleMaps  .

Material examined. BRAZIL, Rio de Janeiro: Cachoeiras de Macacu: Reserva Ecológica de Guapiaçu, 08.VIII.2016, R. Baptista leg., 1 ♂, 1 ♀, 2 juveniles [ MNRJ 7518 (lost), UFRJ 1313, UFRJ 1566].

Diagnosis. Male chelicerae of T. chauliodus  are similar to those of T. keyserlingi  , as both species lack ‘sl’ and share the same position and similar shape of ‘t’, Gu and ‘rsu’ ( Fig. 9D, EView FIGURE 9; Castanheira et al. 2019, figs 8D, E, 10A). However, T. chauliodus  has smaller chelicerae, with more pronounced ‘t’, more elongated and basalward projected Gu, longer and straighter ‘T’, much longer ‘Gl’ and only five additional teeth in ventral row ( Fig. 9View FIGURE 9 D–F). Palps of T. chauliodus  are similar to T. chiyokoae  new species, sharing thin transparent conductor covering the very sclerotized embolus as a thin pouch with large terminal cap, paracymbium with undivided notch, with very wide translucent lobe and large knob ( Figs 7View FIGURE 7 E–G, 9H–J). T. chauliodus  can be distinguished by small tibia, wider terminal cap of the conductor, embolus without straight tip, bearing a terminal curvature and paracymbium with straight distally projected notch, translucent lobe lighter and far from reaching up the notch and knob in a more basal position ( Fig. 8View FIGURE 8 H–J).

Female chelicerae of T. chauliodus  are more alike to those of T. chiyokoae  new species and T. tenuissima  sharing similar elongated upper crests (CRu) and Gu similar in shape and size ( Figs 8AView FIGURE 8, 10D, EView FIGURE 10, 13C, DView FIGURE 13, 14CView FIGURE 14; Okuma 1988b, fig. 40B; Tanikawa 1990, fig. 4). T. chauliodus  and T. chiyokoae  new species are set apart by chelicerae having only Gu on CRu and apart from U2 by large gap, larger Gl, longer L2, and by the fang bearing a basal cusp (BC), besides having longer genital fold ( Fig. 8A, BView FIGURE 8, 10View FIGURE 10 E–G; Okuma 1988b, fig. 40B, F; Tanikawa 1990, figs 3–5). Finally, T. chauliodus  differs from T. chiyokoae  new species by the presence of an extremely elongated median cusp (MC), which is very reduced or absent in the new species ( Fig. 10View FIGURE 10 E–G).

Description. Male: Carapace yellow, elongated, much narrower anteriorly and with two darker thin parallel lines from the cephalic furrow, passing through the fovea, reaching the posterior rim ( Fig. 9AView FIGURE 9). Labium brown and very elongated ( Fig. 9CView FIGURE 9). Sternum light yellow contoured in brown ( Fig. 9CView FIGURE 9). Posterior eyes evenly separate with almost same diameter, AME centrally placed, with moderate gap apart from PME, ALE and PME almost touching. Legs yellow and very elongated ( Fig. 9View FIGURE 9 A–C). Paturon more than 3x longer than wide and little over 60% as long as the carapace, moderately curved outwards, around 45° from the median line of the body ( Fig. 9A, D, FView FIGURE 9), thick, and well carved near the apex, after the insertion of the excavated ‘a’, which is protruding, moderately thick, projected distal- and a little outward, and clearly bent from the middle to the apex ( Fig. 9View FIGURE 9 D–G). ‘t’ small, blunt, upward projected, and located close to ‘a’ ( Fig. 9D, EView FIGURE 9). AXu absent ( Fig. 9D, EView FIGURE 9). Upper row with five uneven teeth ( Fig. 9D, EView FIGURE 9): Gu large, bent basal- and slightly downward, 40% shorter than ‘T’ and apart from it by a significant gap; ‘sl’ absent; ‘T’ thorn-like, long, thin, and almost straight, a little bent downward and ‘rsu’ with three teeth decreasing in size. AXl extremely reduced ( Fig. 9E, FView FIGURE 9). Lower row with six teeth ( Fig. 9E, FView FIGURE 9): Gl long, thin and slightly pointed distalward, adjoined to the basis of the fang alongside L2, both on a soft crest and apart by a small gap; L2–L5 slightly pointing upward, L2 bulkier than L3–L5 which have approximately the same size and L6 much smaller than the others. Cheliceral fang as wide as its base, bent inward and thinner from its proximal end ( Fig. 9View FIGURE 9 D–F). Abdomen cylindrical, slender, around 2.4x longer than the carapace, with six grey patches on each side of its dorsum (the first two lighter) ( Fig. 9View FIGURE 9 A–C). Palps with a very elongated cymbium, bearing thin basis, a slight constriction at the middle, and the distal third thin and slightly curved prolaterally, ending in a roundish point ( Fig. 9View FIGURE 9 H–J); cymbial tarsal organ vey wide, strongly developed ( Fig. 9HView FIGURE 9); tegulum spherical and inflated, more than two times wider than high ( Fig. 9HView FIGURE 9); conductor twisted near mid-way, with thin edges enfolding over the embolus as a thin pouch on its median portion and projected as a small transparent cap near the apex ( Fig. 9H, IView FIGURE 9); embolus thick, originating at the middle portion of the bulb, near the cymbium, with a long leveled curve at the initial portion, followed by a strong upward curve, then a long almost straight median portion and a ‘S’-shaped terminal portion up to the apex, which is hidden by the conductor ( Fig. 9H, IView FIGURE 9); paracymbium wide and elongated, not slanted, tapering toward a finger-like projected notch; translucid lobe wide and long, occupying almost all the ventral side and extending medially for most of the width of the paracymbium; ectal side contoured by a darker line medially and with a large knob, wider than long, with a round tip ( Fig. 9JView FIGURE 9).

Total length 5.93. Carapace 1.74 long, 0.83 wide. Abdomen 4.19 long, 0.60 wide. Left chelicera 1.11 long, 0.34 wide. Leg formula I–IV–II–III. Leg I: femur 5.71, patella 0.64, tibia 5.84, metatarsus 5.94 and tarsus 1.50. Leg II: patella + tibia 3.72. Leg III: patella + tibia 1.40. Leg IV: patella + tibia 3.97.

Female: Carapace color, endites, fovea, eyes, labium and legs as in male ( Fig. 10View FIGURE 10 A–C). Paturon yellow, around 2,7x longer than wide, less than half as long the carapace and gently curved outwards, around 30° from median line of the body, slightly carved near the apex on its upper and outer sides, bearing well projected and distalward teeth on both rows, with CRu facing near the basis of Gu ( Fig. 10View FIGURE 10 D–G). AXu and AXl absent. Upper row with seven teeth ( Fig. 10D, EView FIGURE 10): Gu next to the base of fang and on the distal end of CRu, placed on the top of a deep furrow, apart from U2 by a very large gap, U2–U7 decreasing in size, except by U4 which is smaller and thinner than the others, sharing the same basis with U3. Lower row with eleven teeth ( Fig. 10E, FView FIGURE 10): Gl thicker, less pointed and clearly projected downward than other teeth, apart from L2 by a small gap, L3–L5 decreasing in size, L6–L8 also decreasing in size but longer than L5, L9 smaller than all teeth and followed by L10 and L11 with about the same size of L5. Cheliceral fang straight and wide at the basis, abruptly tapering and basalward slanting from its mid-way on, closing between both rows and bearing a small pyramidal basal cusp (BC) and am elongated thumb-like median cusp (MC) at the final of the basal fourth, projected both basal- and downward ( Fig. 10View FIGURE 10 D–G). Abdomen with same shape as in male but nude, around 3x longer than the carapace ( Fig. 10View FIGURE 10 A–C), dorsally pale beige, covered by guanine spots, scantier at the middle line, with a pale patch on folium ( Fig. 10A, BView FIGURE 10). Venter pale brown, flattened and nude, with neither drawings nor patches ( Figs. 10CView FIGURE 10). Genital fold approximately 1.6x wider than long, large, elongated and laterally compressed in half of its length, with a blunt and straight tip ( Fig. 10HView FIGURE 10). As this female is one of a kind, the vulva was not dissected, but it can be easily observed in Zhu et al. (2003, fig. 59G) and bears two small rounded spermathecae connected to a large subquadrate uterus externus and a slender cylindrical centrally placed central membranous sac.

Total length 8.21. Carapace 2.09 long, 0.87 wide. Abdomen 6.11 long, 0.64 wide. Left chelicera 0.97 long, 0.36 wide. Leg formula I–IV–II–III. Leg I: femur 5.15, patella 0.77, tibia 5.87, metatarsus 5.92 and tarsus 1.53. Leg II: patella + tibia 3.87. Leg III: patella + tibia 1.50. Leg IV: patella + tibia 4.08.

Synonymic notes and variation. In the original description of Tetragnatha chauliodus, Thorell (1890: 292)  cited many somatic characters, but included no illustrations. He based the species on a couple from Singapore and an additional female from Malaysia. He clearly cited the presence of a long MC in the fang of the females he exam- ined ( Thorell, 1890: 295). Afterwards, many authors redescribed T. chauliodus  , based on specimens from different countries, with comprehensive illustrations of chelicerae and genitalia of both sexes (e.g. Okuma, 1987, 1988b; Okuma et al., 1993; Tanikawa, 1990; Song et al., 1999; Zhu et al., 2003). However, there are at least two different species identified and illustrated as T. chauliodus  , sometimes with males and females not well-matched.

The male and female syntypes of T. chauliodus  from Singapore ( Fig. 11View FIGURE 11 A–C) belong to just one species. We herein formally designate the male from Singapore as lectotype. Both the female from Singapore (examined through photos) and the one from Malaysia (not examined) are then regarded as paralectotypes. Our choice is based on the order of description and measurements on Thorell (1890). Typical males of T. chauliodus  , characterized, for example, by Gu very pointed, curved basalward, large ‘t’ and thin and pointed Gl, have been associated with females bearing long MC and robust, straight Gl, as in the Singapore syntypes or our Brazilian specimens ( Figs. 9View FIGURE 9 D–F, 10C).

In his paper on spiders from India, Gravely (1921) cited T. chauliodus  in a section on previously described oriental species of Tetragnatha  that could possibly occur in that country. He gave a brief redescription of it, directly based on Thorell’s original description, without any mention to Indian specimens. Okuma (1987, fig. 15) was the first author to illustrate true females of T. chauliodus  , adding Papua New Guinea to the species distribution. Following Roewer (1942), she also cited T. chauliodus  for Burma [currently Myanmar]. Other doubtful record was given by Okuma (1988b) for Thailand. As all three authors have failed to cite any specimens or previous citations for those countries and we have not also been able to found any actual specimen from them, we do not include India, Myanmar or Thailand in the species distribution, in contrast to the World Spider Catalog (2020).

Okuma (1988b) also misidentified part of the specimens she used on her redescription of T. chauliodus  , illustrating typical male and female of T. chiyokoae  new species from Taiwan as this species. She associated those males with females from several countries from Australasia, differing in the presence and size of the median cusp, considering this character as variable within the species. She mentioned that females from Southern countries, as Singapore and Papua New Guinea, had long MC, Philippine specimens had intermediate MC, while specimens from Northern countries, as Taiwan, had small or absent MC. We have not been able to examine female specimens cited by Okuma, but we do not believe that all her females belong to one and the same species, as we pointed above in the diagnosis and notes section of T. chiyokoae  new species.

Our studies reveal that females from China, Taiwan and Japan have usually been collected associated with typical T. chiyokoae  new species males (e.g, Okuma, 1988b, fig. 40A–G, Tanikawa 1990, figs 1–9). On the other hand, female specimens from southern countries, as the Singapore paralectotype or our specimen from Brazil, were found at the same localities as typical T. chauliodus  males.

Actual females of T. chauliodus  have paturon shorter and bulkier, Gu not quite sclerotized, with large basis connected to the CRu, Gl medium-sized, transversally placed pointing midway from the inner side, L2 longer and thin, fangs almost straight from the middle third on, without concavity or keel at its inner margin, with long and clearly visible MC ( Fig. 10View FIGURE 10 D–G), contrasting to the same structures in T. chiyokoae  new species ( Fig. 8A, BView FIGURE 8). We have not examined any intermediate specimen between the two kinds of females, but we cannot rule out that there may be variation on the cited characters, as in the Philippine specimen cited by Okuma (1988b). However, only a thorough examination of many specimens from Australasia in a future work will settle this question. For now, we prefer to follow the data we have and associate the two kinds of females examined to the males collected at the same areas.

Another important bit of information on this question was given by Zhu et al., 2003. They redescribed females (fig. 59A–G) and males (fig. 60A–G) of “ T. chauliodus  ” and gave a handful of records from Yunnan and Hainan provinces, China, besides describing a new species, T. zhangfu Zhu et al. 2003  (fig. 107A–I), also from Yunnan, China. They misidentified the male of T. chiyokoae  new species as T. chauliodus  , probably following Okuma (1988b) and Tanikawa (1990), describing the actual T. chauliodus  male as T. zhangfu  . After examining photos of T. zhangfu  holotype ( Fig. 11View FIGURE 11 D–G), we concluded that it has small differences on chelicerae and genitalia, but it clearly belongs to the real T. chauliodus  , matching well with photos of the male lectotype of this species ( Fig. 11A, BView FIGURE 11). Therefore, we herein synonymize T. zhangfu Zhu et al. 2003  with T. chauliodus Thorell, 1890  new synonymy.

MAP 2. Distribution of T. megalocera  new species and the first record of T. chauliodus  for the Neotropics.

The female Zhang et al. (2003) associated to the male of T. chiyokoae  new species actually belongs to T. chauliodus  . The female of T. chauliodus  , the male of T. chiyokoae  new species (considered as T. chauliodus  ) and the actual male of T. chauliodus  (holotype of T. zhangfu  ) have all been collected at the same locality: Meilun (or Meilong) county, Yunnan province (21°54’N, 101°12’E). For the best of our knowledge, this is the only area where both species have been collected together.

Finally, it is important to highlight that due to the terrible fire that destroyed MNRJ collection, the one and only male specimen of T. chauliodus  we collected was destroyed. Because photos were previously taken (except the detailed SEM photos), it was possible to proceed with its redescription above. Furthermore, despite the strong collecting effort at the type-locality throughout the last three years during a yet unpublished taxonomic survey in Reserva Ecológica de Guapiaçu, Rio de Janeiro state, Brazil, we were not able to collect any other specimens of T. chauliodus  .

Distribution. This species is originally recorded from Asia, ranging from China in the North to Malaysia and Singapore in the Southeast, and also Papua New Guinea in Oceania, after Okuma (1987). In the Neotropical region, the first and only record of this species is from Reserva Ecológica de Guapiaçu, Cachoeiras de Macacu, Rio de Janeiro state, Brazil (Map 2). Additionally, the record given by Okuma (1988b) for Philippines may be correct, but we have not been able to examine specimens from this country. The collection of this species in Brazil may indicate that is has a larger but still undocumented distribution throughout the world.

NHRS

Swedish Museum of Natural History, Entomology Collections

R

Departamento de Geologia, Universidad de Chile

MNRJ

Museu Nacional/Universidade Federal de Rio de Janeiro

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Tetragnathidae

Genus

Tetragnatha

Loc

Tetragnatha chauliodus ( Thorell, 1890 )

Castanheira, Pedro De Souza & Baptista, Renner Luiz Cerqueira 2020
2020
Loc

T. chauliodus: Basu & Raychaudhuri, 2016: 219

Basu, D. & Raychaudhuri, D. 2016: 219
2016
Loc

T. chauliodus: Tanikawa, 2009: 416

Tanikawa, A. 2009: 416
2009
Loc

T. chauliodus: Tanikawa, 2007: 108

Tanikawa, A. 2007: 108
2007
Loc

Tetragnatha zhangfu

Zhu, M. S. & Song, D. X. & Zhang, J. X. 2003: 197
2003
Loc

T. chauliodus:

Zhu, M. S. & Song, D. X. & Zhang, J. X. 2003: 128
Song, D. X. & Zhu, M. S. & Chen, J. 1999: 221
1999
Loc

T. chauliodus:

Okuma, C. & Kamal, N. Q. & Hirashima, Y. & Alam, M. Z. & Ogata, K. 1993: 44
1993
Loc

T. chauliodus: Tanikawa, 1990: 9

Tanikawa, A. 1990: 9
1990
Loc

T. chauliodus: Okuma, 1988b: 196

Okuma, C. 1988: 196
1988
Loc

T. chauliodus:

Okuma, C. 1987: 62
1987
Loc

Tetragnatha chauliodus:

Gravely, F. H. 1921: 425
1921
Loc

Limoxera chauliodus

Thorell, T. 1890: 292
1890