Primer registro de un regalo nupcial en Trechalea amazonica (Araneae, Lycosoidea, Trechaleidae)

Estevam Luís Cruz da Silva¹ ; Arno Antonio Lise¹

¹ Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Museu de Ciências e Tecnologia (MCTP), Laboratório de Aracnologia, Prédio 40, sala 167, Av. Ipiranga, 6681, 90619-900, Porto Alegre, Rio Grande do Sul, Brasil.
E-mail Estevam Cruz: estevamsilva@gmail.com ; Arno Lise lisearno@pucrs.br

ABSTRACT

The first record of a nuptial gift in Trechalea amazonica F.O.P.-Cambridge, 1903, is herein presented. The observations were made in the Oriximiná, Pará, northern Brazil. Two males were found on tree trunks near the water, each holding in the chelicerae a small prey wrapped in silk. This is the second confirmed observation of the nuptial gift behavior in the family Trechaleidae, first in the genus Trechalea Thorell, 1869, and later in Paratrechalea Carico, 2005 from southern Brazil. This new observation could be used in phylogenetic and evolutionary studies for this poorly studied spider family.

Keywords: Araneae, nuptial gift, Neotropical region.

RESUMEN

Se presenta el primer registro de un regalo nupcial en Trechalea amazonica F.O.P - Cambridge, 1903. Las observaciones se hicieron en el pantanal de Oriximiná, Pará, Brasil. Se encontraron dos machos en troncos de árboles cerca del agua, cada uno cargando en los quelíceros una presa pequeña envuelta en seda. Ésta es la segunda observación confirmada del comportamiento nuptial del regalo en la familia Trechaleidae, primero en el género Trechalea Thorell, 1869, y más adelante adentro Paratrechalea Carico, 2005 del Brasil meridional. Esta nueva observación se podría utilizar en estudios filogeneticos y evolutivos para esta familia.

Palabras clave: Araneae, regalo nupcial, region Neotropical.

Introduction

The use of nuptial gifts in spiders was first observed in males of Pisaura mirabilis (Clerck, 1757) (Bristowe & Locket 1926). This behavior, previously known only for pisaurid spiders, has been recently reported for a few trechaleid species (Costa-Schmidt et al. 2008).

In the Neotropical region, the first record of a nuptial gift for a non-pisaurid specimen was reported by Silva (2005) for Trechalea bucculenta (Simon 1898), a member of the family Trechaleidae. Later, this behavior was described in detail after field observations made by Costa-Schmidt et al. (2008), for Paratrechalea azul Carico, 2005 and P. ornata (Mello-Leitão 1943), in Maquiné, Southern Brazil. Recently, Albo et al. (2009) have observed the same behavior of nuptial gift construction in populations of Paratrechalea ornata (Mello-Leitão, 1943) from Uruguay.

In the city of Oriximiná, northern Brasil (01°45'S, 55°50'W), two males were observed on tree trunks near the water, each holding in the chelicerae a small, wrapped prey, consisting of an immature Ctenidae spider for one of them and an immature Lycosidae spider for another one (Figs. 1, 2). The males holding the eggsacs is certainly an indication of nuptial gift behavior, since all the representatives of Trechaleidae usually eat their preys without making any wrapping, observed by Silva et al. (2005) for the predatory behavior of Trechaleidae. Also, some females were observed carrying eggsacs in tree trunks (Fig. 3) The presence of females with eggsacs indicates the activity of mature males in the area, thus it can explain the presence of many males with nuptial gifts (field observations).

The specimens were collected manually and deposited in the collection of Arachnida and Myriapoda of Museu de Ciências e Tecnologia (MCTP) of Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS). The area was sampled from January 17^th to February 7^th in 2009 in Iripixi Lake, in the city of Oriximiná, state of Pará, Northern Brazil (Fig. 4).

Acknowledgments

We want to thank Francisco de Aguiar Picanço for help with the field work and Dr. James E. Carico (Lynchburg College) for comments on the manuscript. This study was supported by "Conselho Nacional de Desenvolvimento Científico e Tecnológico" (CNPq N° 140282/2008-4 for ELCS).

Literature cited

Albo, M. J., L. E. Costa-Schmidt & Costa, F. G. 2009. To feed or to wrap? Female silk cues elicit male nuptial gift construction in the spider Paratrechalea ornata (Trechaleidae). Journal of Zoology, 2009: 1-7.

Bristowe, W. S. & Locket, G. H. 1926. The courtship of British lycosid spiders, and its probable significance. Proceedings of the Zoological Society 22:317_347.

Costa-Schmidt, L. E.; J. E. Carico & A. M. Araújo. 2008. Nuptial gifts and sexual behavior in two species of spider (Araneae, Trechaleidae, Paratrechalea). Naturwissenschaften 95:731_739.

Silva, E. L. C. 2005. New data on the distribution of Trechalea cezariana Mello-Leitão, 1931 in Southern Brazil. Acta Biologica Leopoldensia 27(2):127_128.

Silva, E. L. C.; Picanço, J. B. & A. A. Lise. Notes on the predatory behavior and habitat of Trechalea biocellata (Araneae, Lycosoidea, Trechaleidae). Biociências 13(1):85_88.

Presentado: 05/03/2009
Aceptado: 05/06/2009
Publicado online: 28/08/2009