Tetragnatha nitens (Audouin, 1826)

Castanheira, Pedro de Souza, Baptista, Renner Luiz Cerqueira & Oliveira, Francisca Samia Martins, 2022, Five new species of the long-jawed orb-weaving spider genus Tetragnatha (Araneae, Tetragnathidae) in South America, with a key to the species from Argentina and Brazil, Evolutionary Systematics 6 (2), pp. 175-210 : 175

Tetragnatha nitens (Audouin, 1826)

Figs 12 , 13

Tetragnatha extensa (Linnaeus, 1758): Nicolet, 1849: 516, plate 4, figs 5, 5a-d (female, misidentified).

Eugnatha nitens Audouin 1826: 118, plate 2, fig. 2 (female).

Tetragnatha nitens : Walckenaer 1841: 209.

Tetragnatha labialis Nicolet 1849: 520 (female). New Synonymy.

Tetragnatha labialis : Keyserling 1865: 851, plate 21, figs 11-13 (male and female misidentified).

Tetragnatha americana Simon, 1896: CV-CVI (sex?), New Synonymy.

Tetragnatha labialis Simon, 1896: CVII (sex?); 1902: 25; 1904: 94.

Tetragnatha americana : Simon, 1905: 10 (male, female, misidentified).

Type-material.

Tetragnatha americana : Unspecified number of syntypes from Peñaflor, Santiago, Chile, Lataste Coll., MNHN?, MHNS?, presumed lost. Tetragnatha labialis : Unspecified number of adult female syntypes from Santiago, Chile, Nicolet Coll. (female MNHN 4209, herein designated as lectotype), examined.

Additional Record.

Chile - • 1 male from Punta Arenas ( T. americana : Simon det., MNHN 22312), examined.

Notes.

Tetragnatha americana was a new name Simon (1896, p. CV-CVI) applied to a species he considered as the same one misidentified as T. extensa and redescribed by Nicolet (1849, p. 516). He only added the following expression in a list of spiders from Chile assembled by F. Lataste: " Tetragnatha americana E. Sim. (= Tetragnatha extensa Nicolet)". Those specimens were collected in Peñaflor, Santiago, Chile, and deposited at the "Museo Zoolojico de la Escuela de Medicina", currently the Museo Nacional de Historia Natural, Chile (MHNS, see Díaz (2019) for additional information). Simon (1905, p. 10) applied again without any justification the name T. americana to the species he considered as T. extensa sensu Nicolet, citing three females from Santa Cruz, Argentina. He listed T. extensa sensu Nicolet under the title of Tetragnatha americana , and included the bibliographical reference to the book, again without mentioning the examination of Nicolet’s specimens or any morphological character. Simon (1905) added that the specimens he had from Santa Cruz "were not different from T. americana of Chile, where the species is very common".

Despite Simon (1896, 1905) not clearly stating that he intended to add a new replacement name for T. extensa sensu Nicolet, no previous citation to T. americana was found after an analysis of Simon’s papers dealing with spiders from Chile. Following Bonnet (1959, sub " T. americana Simon, 1897", p. 4317) and against Roewer (1942, p. 988) and the World Spider Catalog (2022), we consider 1896 and not 1905 as the year of the proposition of the new name T. americana . The citation by Simon (1896, p. CV) was apparently the first appearance of the name and it is available under the International Code of Zoological Nomenclature (ICZN 1999), following its article 12, which establishes that an unambiguous reference to a species’ description suffices to make available a name published before 1931.

The type-series of T. americana Simon, 1896 is therefore composed of the specimens from Peñaflor examined by Simon (1896) when proposing the new name and also the specimens from Valdivia province studied and illustrated by Nicolet (1849), but not by the specimens from Santa Cruz, Argentina (Fig. 11 ) and unspecified localities of Chile cited by Simon (1905). According to the article 72.4.1.1 and its example, all the specimens studied by the species’ author or referred unambiguously to in the original description constitute the type series. As stated by Levi (1967, 2001), Nicolet probably returned to Paris in 1846 and brought with him a large part of the types of Chilean species he described. Levi was able to find at MNHN types of many species of Theridiidae , but he considered most Araneidae types as lost. We also have not been able to find most Tetragnathidae types of species described by Nicolet in MNHN, excepting T. labialis . We requested information about Tetragnatha specimens from the MHNS but did not receive an answer and there is no evidence that any of Nicolet or Simon’s specimens are still available in this institution. Because T. labialis was found in MNHN, we consider that this was probably the same depository institution for the other species described by Nicolet (1849) and the specimens from Valdivia province described as T. extensa . However, except for T. labialis , no other original specimen from Nicolet (1849) was found at MNHN. Likewise, T. americana specimens identified by Simon from Peñaflor and Santiago were also not found in the general collection of the MNHN. Therefore, we consider the syntypes of T. americana presumed lost.

Nicolet’s description focused on the shape and size of structures such as carapace, eyes, abdomen, chelicerae and pedipalps, but did not include precise details on chelicerae and genital morphology to allow species identification. Fortunately, he also provided relatively good drawings ( Nicolet 1849, plate 4, fig. 5), which clearly depict a female specimen of T. nitens , based for example on the sinuous cheliceral fang, Gu and U2 large and of similar size and well-spaced, and AXl large but not overreaching the fang basis. So, the description and illustrations by Nicolet (1849) are the only reliable information on the type series we recovered.

We were able to analyse all the specimens currently present in the MNHN collection and identified as T. americana by Simon. Some of these are specimens of T. laboriosa , represented by several specimens from Chile (MNHN 12628) and just one of the three females from Santa Cruz, Argentina (MNHN 3140, Fig. 11 ) cited by Simon (1905). On the other hand, there is a male from Punta Arenas, Chile, that is clearly T. nitens (MNHN 22312, Fig. 12 ). Although these specimens are just additional material examined, they were identified by Simon himself, thus helping to establish his concept of T. americana . Although some specimens Simon identified as T. americana are in fact T. laboriosa , the original drawings of a female syntype of " T. extensa " from Nicolet and secondarily the male from Punta Arenas (MNHN 22312, Fig. 12 ) identified by Simon allow us to indicate that Tetragnatha americana Simon, 1896 is Tetragnatha nitens (Audouin, 1826) syn. nov.

As mentioned above, the only species dealt with by Nicolet (1849) that we were able to locate at MNHN was T. labialis , described based on an unspecified number of female syntypes from Santiago, Chile. A female specimen (MNHN 4209), labelled as " Tetragnatha labialis Nicol. Gay Saint Iago" (Fig. 13 ) was examined. This female clearly belongs to the syntype series examined by Nicolet and is herein designated as lectotype. Following Castanheira et al. (2019), this specimen is clearly T. nitens , as shown for example by the following diagnostic cheliceral characters: Gl distalward followed by smaller L2 and L3, AXl reduced and point distalward, Gu elongated and not contiguous to U2 and robust basal cusp placed at the lower side of fang (Fig. 13A-C ). Therefore, we propose Tetragnatha labialis Nicolet 1849 = Tetragnatha nitens (Audouin, 1826) syn. nov. Additionally, the male and female specimens from Nova Granada (probably Colombia) named T. labialis by Keyserling (1865) are misidentified. The original drawings of the chelicerae resemble T. argentinensis ( Keyserling 1865, fig. 11-13) or perhaps some related, undescribed species from Colombia. Furthermore, the original locality (Nova Granada) is too far north of the currently known T. argentinensis distribution range ( Cargnelutti et al. 2022). The Chilean specimens of T. labialis cited by Simon (1902, 1904) from Valdivia and Punta Arenas, respectively, were not found at MNHN. Only a male from T. americana from Punta Arenas was located as we explained above (Fig. 12 ).

Figures

Figure 11. Tetragnatha laboriosa under T. americana, female (MNHN 3140). A. Dorsal habitus; B. Original label citing Santa Cruz, Argentina; C. Ventral habitus; D. Left chelicera, inner view; E. Chelicerae, apical view.

Figure 12. Tetragnatha nitens under T. americana, male. A. Left chelicera, inner view; B. Chelicerae, slanted lower view.

Figure 13. Tetragnatha nitens under T. labialis, female lectotype (MNHN 4209). A. Left chelicera, upper view; B. Left chelicera, inner view; C. Left chelicera, lower view; D. Original label.