Alpaida atomaria
Creators: name: Baptista, Renner Luiz Cerqueira
name: Castanheira, Pedro De Souza
name: Prado, André Wanderley Do
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Araneidae
Alpaida
Alpaida atomaria

description: Alpaida atomaria (Simon, 1895)
(Figs. 9–10, Map 2)
Salassina atomaria Simon, 1895: 781
Edricus atomarius: Petrunkevitch, 1911: 337
Alpaida atomaria: Levi, 1988: 458, fig. 479–482 Alpaida lanei Levi, 1988: 412, fig. 170–171. New synonymy
Type material. Alpaida atomaria: BRAZIL: 2♀, syntypes, Rio de Janeiro, Rio de Janeiro, Parque Nacional da Tijuca (MNHN 8515), not examined.
Alpaida lanei: BRAZIL: ♂, holotype, São Paulo, São Paulo, Horto Florestal (coll. F. Lane, MZUSP 4547), not examined; ARGENTINA: ♂, paratype, Misiones, General Manuel Belgrano (coll. M. E. Galiano, MACN 8449), examined.
Synonymy justification. Simon (1895) first described Alpaida atomaria based on two female syntypes from Tijuca, Rio de Janeiro city, Brazil (MNHN 8515, not examined). Levi (1988) redescribed the species, recording it also from Represa Rio Grande, a small dam at Parque Estadual da Pedra Branca, a locality nearby Tijuca. In the same paper, Levi described the male of A. atomaria under the name of Alpaida lanei (see Levi, 1988, p. 412, fig. 170–171), based on a male holotype from Horto Florestal, São Paulo (MZSP 4547, not examined) and a paratype from General Manuel Belgrano department, province of Misiones, Argentina (MACN 8449, examined). The only other citations of Alpaida atomaria and A. lanei in the literature are the records of both species for Cotia, São Paulo state, Brazil (Nogueira et al. 2006) and Nova Lima, Minas Gerais state (Azevedo et al. 2014). An analysis of the data contained in the Specieslink database (CRIA, 2017) shows additional specimens of both species from Parque Estadual da Cantareira, São Paulo state (MZSP), and of only Alpaida lanei from Pariquera-Açu (UBTU 1216), São Paulo state, Florianópolis, Santa Catarina state (MCTP 4037, 4985, 5369, 7528) and Santa Maria, Rio Grande do Sul state (MCTP 40872), all in Brazil.
The synonymy of A. lanei with A. atomaria is based on the many examples of co-occurrence of both species throughout their geographic range and on similarities on colour pattern and abdominal shape. Males of A. lanei and females of A. atomaria were both collected in many localities (sometimes together at the same web), for example, at Parque Nacional da Tijuca, Parque Estadual da Pedra Branca and Parque Natural Municipal do Marapendi, all three in Rio de Janeiro city, and Macaé, Rio de Janeiro state. Furthermore, there are records of co-occurrence of both species in Serra da Cantareira, São Paulo city, São Paulo state, and Nova Lima, Minas Gerais state (both in the Specieslink), besides Cotia, also in São Paulo state (Nogueira et al. 2006). The colour pattern of both male and female are very similar, with carapace usually bearing a median dorsal black V-shaped mark (filled anteriorly with black and brown pigment on most females) (Fig. 9A, 10A), sternum uniformly yellow (Fig. 9C, 10C), abdomen with dorsum bearing two irregular, interrupted longitudinal black stripes on the sides, a pair of large black spots at sides of the anterior third portion, adjoined to the longitudinal stripes (covering the inner side of the humps, when present) and one or two transverse irregular black stripes at the posterior third (Fig. 9A–B, 10A–B), venter with a large median interrupted black stripe and two irregular sets of black stripes on the sides over a pale yellow background, and black spinnerets (Fig. 9C, 10C). The legs have also a similar colour pattern, with black coxa and trochanter and the other articles yellow, with black or dark brown spots throughout, especially on the dorsum of the femur (Fig. 9A–C, 10A–C). The elongated, roundish abdomen has also similar features in both sexes, with an acute posterior tip, placed over a white spot and two humps at the sides of anterior third (small or even absent on males) (Fig. 9A–B, 10A–B).
It is understandable why Levi (1988) had not paired males and females in his revision paper on Alpaida. The males of A. lanei were collected in São Paulo state, Brazil, and Misiones province, Argentina, both localities south from Rio de Janeiro city, the type-locality of A. atomaria. The males of A. lanei Levi examined lacked the black Vshaped marks on the dorsum of the carapace and lacked the dorsal humps and acute posterior tip of the abdomen (Fig. 9D–E, Levi 1988, fig. 170). On the other hand, the female syntypes of A. atomaria had a pointed median hump at the anterior border and additional humps on the median portion of the dorsum (Levi 1988, fig. 481 and 482). Several female specimens we examined have much smaller humps (Fig. 10A–B) or even lack them at all. However, the dimorphism in abdominal shape in Alpaida species with humps is well-known, with males bearing attenuate and more roundish abdomen, for example, in Alpaida chickeringi Levi, 1988 or Alpaida lubinae Levi, 1988.
The colour and shape of the abdomen are largely variable in this species. Sometimes, the dorsum of the abdomen lacks most of the black pigment in males (Fig. 9D) and may even be uniform black in females. One female specimen (MNRJ 1564) had even burgundy hues over the carapace, sternum and the venter and sides of the abdomen when alive.
Natural History. Most specimens were collected in small orbicular webs (10–12 cm wide) in shaded places usually more than 1 m above ground, among shrubs or near tree trunks or rock walls. The spider remains in the hub of the horizontal or little tilted web during day and night. “Looking up” and “beating” techniques yielded almost all the collected spiders.
New records. BRAZIL, Espírito Santo: Anchieta: CSV (Urubu), 18.VIII.2008, looking up, R. Baptista coll., 1 ♂ (UFRJ 1394); Rio de Janeiro: Cachoeiras de Macacu: Reserva Ecológica de Guapiaçu, 8–12.xi.2001, A. Giupponi, A. P. González, D. R. Pedroso & D. Frota coll., 1 ♂ (MNRJ 1636); Casimiro de Abreu: BR-101 (station 4— Túlio), 11.VIII.2010, D. Castro coll., 1 ♂ (UFRJ 1413); Macaé: Terminal Cabiúnas (Mata da Fazenda), 29.III.2010, beating, R. Baptista coll., 1 ♀ (UFRJ 1461); idem, Terminal Cabiúnas (Mata da Odebei), 18.III.2011, beating, R. Baptista coll., 1 ♂, 1 immature (UFRJ 1462); 22.V.2013, beating, D. Pedroso coll., 1 ♀ (UFRJ 1396); 23.V.2013, beating, G. Miranda coll., 1 ♀ (UFRJ 1397); 21.XI.2013, beating, G. Miranda coll., 1 ♀ (UFRJ 1398); 20.II.2014, beating, O. Villareal coll., 1 ♂ (UFRJ 1399); 20.II.2014, looking up, O. Villareal coll., 1 ♂ (UFRJ 1400); 20.XI.2014, looking up, D. Pedroso coll., 1 ♂ (UFRJ 1401); idem Terminal Cabiúnas (Mata do Gasoduto), 22.XI.2016, beating, D. Pedroso coll., 1 ♂ (UFRJ 1402); Magé: Andorinhas, 19.IV.1987, R. Baptista coll., 1 ♀ (MNRJ 1564); Mendes: Fazenda Arvoredo (Encruzilhada) 22° 30’ 16.8” S, 043° 45’ 34.6” W, 510 m, 31.VIII.2014, beating, R. Baptista coll., 1 ♀ (UFRJ 1403); 0 3.III.2015, looking up, R. Baptista, 1 ♀ (UFRJ 1 404); idem Centro Marista São José das Paineiras (Sede) 22 ° 30’ 35.1” S, 043° 45’ 16.5” W, 551 m, 25.II.2015, looking up, A. do Prado, 1 ♀ (UFRJ 1405); Rio de Janeiro: Parque Municipal Natural do Marapendi, 06.XII.2008, cryptic, R. Baptista et. al. coll., 1 ♀ (UFRJ 1471); 06.XII.2008, beating, R. Baptista et. al. coll., 1 ♂ (UFRJ 1472); idem, Parque Estadual da Pedra Branca, Camorim (Sede) 22° 58’ 12.0” S, 043° 26’ 16.4” W, 160 m, 02.VI.2013, beating, R. Baptista coll., 1 ♂, 1 ♀ (UFRJ 1406); 02.VI.2013, looking up, R. Baptista coll., 3 ♀, 1 immature (UFRJ 1407); 15.IX.2013, looking up, R. Baptista coll., 1 ♂ (UFRJ 1408); 16.XII.2013, beating, P. Castanheira coll., 1 ♂ (UFRJ 1409); idem, Camorim (Açude trail) 22° 58’ 08.3” S, 043° 26’ 38.5” W, 342 m, 02.VI.2013, beating, R. Baptista coll., 1 ♂, 1 immature (UFRJ 1395); idem, Pau-da-Fome (Figueira trail) 22° 55’ 57.0” S, 043° 26’ 32.3” W, 138 m, 23.IX.2013, looking up, R. Baptista coll., 1 ♀ (UFRJ 1410); 09.XII.2013, looking up, P. Castanheira coll., 1 ♀ (UFRJ 1463); 15.III.2014; looking up, R. Baptista coll., 1 ♀ (UFRJ 1411); idem, Pau-da-Fome (Padaria trail) 22° 56’ 12.8” S, 043° 26’ 29.1” W, 133 m, 13.VI.2013, R. Baptista coll., 1 ♀ (UFRJ 1412); idem, Parque Nacional da Tijuca, 28.IX.1985, R. Baptista coll., 1 ♀ (MNRJ 07439); 16.VI.1994, R. Baptista coll., 1 ♂, 1 ♀ (MNRJ 07437); idem, Parque Nacional da Tijuca (Trilha do Archer), 16.VI.1994, R. Baptista coll., 1 ♀ (MNRJ 07440); Silva Jardim: BR-101 (station 3—Daniel), 05.VIII.2010, looking up, P. Castanheira coll., 1 ♂ (UFRJ 1393); 04– 11.VIII.2010, P. Castanheira coll., 1 ♂ (UFRJ 1414); São Paulo: Ubatuba: Parque Estadual da Serra do Mar, Núcleo Picinguaba, VII.2006, R. Baptista coll., 1 ♀ (UFRJ 1464).
Distribution. From central Minas Gerais State, Brazil, to northern Misiones Provincia, Argentina and central Rio Grande do Sul state, Brazil (Map 2).
description: Published as part of Baptista, Renner Luiz Cerqueira, Castanheira, Pedro De Souza & Prado, André Wanderley Do, 2018, Notes on the orb-weaving spider genus Alpaida (Araneae, Araneidae) with description of four new species from Rio de Janeiro, Brazil, pp. 321-345 in Zootaxa 4407 (3) on pages 335-338, DOI: 10.11646/zootaxa.4407.3.2, http://zenodo.org/record/1216546