Leptodrassus albidus and Setaphis carmeli are reported for the first time for the Canary Islands, on the islands of Tenerife and Gran Canaria, respectively. Also, another 13 species representing first records for some of the individual Canarian major islands are reported. Habitats of collected specimens are described and global distribution of the species is provided.
The Canary Islands are an archipelago of volcanic origin located off northwest Africa, comprising seven major islands: El Hierro, La Palma, La Gomera, Tenerife, Gran Canaria, Fuerteventura and Lanzarote. Their contrasting topography and large temperature and humidity gradients provide major opportunities for speciation in spiders (Carvalho & Cardoso 2010), thus compensating their relatively low richness compared to the African and European continents for a very high level of endemism (Cardoso et al. 2010). To date there are 513 spider species recorded, most of them endemisms (65%) and only 17 introduced (3%) (Gobierno de Tenerife 2017). The highest richness is reached on the island of Tenerife (278 species) while Lanzarote, with 98 species, harbours the lowest number of spider species (Fig. 1). Some of the factors that influence spider biodiversity on each island are habitat heterogeneity, geological age, distance to the continent, area and elevation (Cardoso et al. 2010, Real et al. 1999).
Several studies have focused on the spider biodiversity from the Canary Islands, both at taxonomic (e.g., Dimitrov & Ribera 2007, Lissner 2017, Planas & Ribera 2015, Wunderlich 1987,1992,2011), faunistic (e.g., Hepner & Paulus 2009, Hernández-Teixidor et al. 2011, Macías-Hernández et al. 2016) and genetic levels (e.g., Dimitrov et al. 2008, Macías-Hernández et al. 2010,2013, Opatova & Arnedo 2014). Most of them have been carried out within the families Dysderidae and Pholcidae, which had experienced a huge adaptive radiation leading to several endemic species (Arnedo et al. 2001, Dimitrov et al. 2008). However, the real distribution of many species is underestimated, especially in islands and habitats that have been poorly sampled. In this article the known distribution of fifteen species is extended, reporting nine first records for Gran Canaria, four for Tenerife, and three for Fuerteventura (one of them also shared with Gran Canaria). Moreover, Leptodrassus albidus Simon, 1914 and Setaphis carmeli (O. Pickard-Cambridge, 1872) are reported for the first time for the Canary Islands.
Material and methods
All specimens were collected by direct sampling and identified by the author from December 2016 to August 2017, except when another collector is specified, and all are stored in absolu te ethanol in the author's personal collection. Murphy (2007), Nentwig et al. (2017), Platnick & Murphy (1996) and Wunderlich (1992) were used as resources to identify the species. Global distribution data were taken from the World Spider Catalog (2017) while current distribution data in the Canary Islands were taken from the Canary Biodiversity DataBase (Gobierno de Canarias 2017). The latter was also consulted to obtain information about insular and local (50 × 50 m squares) spider biodiversity. This tool is the most updated information since the last published check-list (Arechavaleta et al. 2010).
Results
Family Araneidae
Agalenatea redii (Scopoli, 1763)
Determination. Nentwig et al. (2017).
Gran Canaria: Tenteniguada (Valsequillo), 27.975834°N/ -15.528912°W, 1010 m, 28.XII.2016, 1 ♀; Inagua (Tejeda), 27.932508°N/-15.672725°W, 1060 m, 30.XII.2016, 1 ♀; Montaña de Tara (Telde), 28.003147°N/-15.431478°W, 250 m, 10.III.2017, 1 ♀; Valsendero (Valleseco), 28.031515°N/ -15.600947°W, 1220 m, 11.IV.2017, 1 ♀ Camino de Las Retamillas (Moya), 28.039958°N/-15.606447°W, 1375 m, 11.IV.2017,1 ♀; Montaña Las Palmas (Telde), 27.998172°N/ -15.454362W, 530 m, 10.IV.2017,1 ♀.
Fuerteventura: Corral de Esquey (Betancuria), 28.449499°N/ -14.031692°W, 290 m, 28.V.2017,2 ♀♀, Ruymán Cedrés leg. Individuals were found on dry grass and shrubs.
Distribution. Europe, Turkey, Central Asia to China. New to Gran Canaria and Fuerteventura.
Argiope lobata (Pallas, 1772)
Determination. Nentwig et al. (2017).
Gran Canaria: Inagua (Tejeda), 27.932508°N/-15.672725°W, 1060 m, 30.XII.2016,1 ♀.
The collected specimen was found in a web on dry grass.
Distribution. Southern Europe to Central Asia and China, northern Africa, South Africa, Israel, India, from Myanmar to New Caledonia and northern Australia. New to Gran Canaria.
Argiope trifasciata (Forsskål, 1775)
Determination. Nentwig et al. (2017).
Fuerteventura: Puerto Lajas (Puerto del Rosario), 28.538297°N/-13.841662°W, 15 m, 27.V.2017, 1 ♀, R. Cedrés leg.; Antigua, 28.423899°N/-14.023818°W, 580 m, 11.VIII.2017, 1 ♀.
Individuals were found in webs on Launaea arborescens.
Distribution. North, Central and South America. Introduced to Africa, Portugal, Israel, China, Japan, Australia (Tasmania) and Pacific islands. New to Fuerteventura.
Fig. 1 :
Map showing the different islands in the Canary archipelago and the number of spider species harboured by each one (GRAFCAN 2017)
Gnaphosidae
Leptodrassus albidus Simon, 1914 (Fig. 2)
Determination. Murphy (2007).
Tenerife: San Roque (San Cristóbal de La Laguna), 28.487826°N/-16.308622°W, 610 m, 1.V.2017,1 ♀.
The specimen was collected under a rock in a Pinus radiata plantation. It can be easily distinguished from Leptodrassex hylaestomachi Berland, 1934 in having the median cavity of the epigyne covered by a long hood that is lacking in the genus Leptodrassex. This species is the first report of the genus Leptodrassus for the Canary Islands.
Global distribution. Spain to Crete, Turkey, Israel, Azores. New to the Canary Islands.
Setaphis carmeli (O. Pickard-Cambridge, 1872) (Fig. 3)
Determination. Platnick & Murphy (1996).
Gran Canaria: Caldera de los Marteles (Valsequillo), 27.958469°N/-15.535192°W, 1460 m, 8.IV.2017, 2 ♀♀; 21.V.2017,2 ♀♀.
This species was found under rocks in an abandoned crop field. Several juveniles were also observed. Its dark colouration and bicoloured legs makes this species easy to distinguish from the Canary endemisms of the genus Setaphis, which are usually light brown.
Global distribution. Mediterranean. New to the Canary Islands.
Setaphis wunderlichi Platnick & Murphy, 1996
Determination. Platnick & Murphy (1996).
Tenerife: Tam aide (San Miguel de Abona), 28.094245°N/ -16.626681°W, 595 m, 3.IV.2017,1 ♂, Yudith García leg.
The specimen was collected inside a house.
Global distribution. Canary Islands. New to Tenerife.
Trachyzelotes lyonneti (Audouin, 1826)
Determination. Nentwig et al. (2017).
Gran Canaria: Caldera de los Marteles (Valsequillo), 27.958469°N/-15.535192°W, 1460 m, 21.V.2017, 3 ♀♀ 1 ♂ Tenteniguada (Valsequillo), 27.975834°N/-15.528912°W, 1010 m, 21.V.2017,1 ♀.
Specimens were collected under rocks in abandoned crop fields covered by grasses.
Global distribution. Macaronesia, Mediterranean to Central Asia. Introduced to USA, Mexico, Peru and Brazil. New to Gran Canaria.
Tab. 1:
Summary of the new records provided in this article. Previously known distributions are marked with an “X”, while new records are indicated with asterisks (*). H: El Hierro, P: La Palma, G: La Gomera, T: Tenerife, C: Gran Canaria, F: Fuerteventura, L: Lanzarote.
Mimetidae
Ero flammeola Simon, 1881
Determination. Nentwig et al. (2017).
Gran Canaria: Tenteniguada (Valsequillo), 27.975834°N/ -15.528912°W, 1010 m, 15.IV.2017,1 ♀.
The individual was collected on a wall of a rural house.
Global distribution. Portugal to Corfu, Turkey, Israel, Canary Islands. New to Gran Canaria.
Salticidae
Pellenes nigrociliatus (L. Koch, 1875)
Determination. Nentwig et al. (2017).
Gran Canaria: Tenteniguada (Valsequillo), 27.975834°N/ -15.528912°W, 1010 m, 15.IV.2017,1 ♂.
The specimen was found on a wall.
Global distribution. Canary Is., Europe, Turkey, Israel, Caucasus, Russia to Central Asia, China. New to Gran Canaria.
Phlegra bresnieri (Lucas, 1846)
Determination. Nentwig et al. (2017).
Tenerife: Los Rodeos (San Cristóbal de La Laguna), 28.471603°N/-16.347847°W, 680 m, 7.III.2017, 1 ♀, Javier García leg.
It was collected under a rock in a crop field.
Global distribution. Southern Europe, Northern Africa to Turkey, Azerbaijan, Iran. New to Tenerife.
Thyene imperialis (Rossi, 1846)
Determination. Nentwig et al. (2017).
Fuerteventura: Puerto de Morro Jable (Pájara), 28.049671°N/ -14.357968°W, 5 m, 14.VIII.2017,1 ♂, 1 ♀.
Both individuals were found on leaves of Euphorbia balsamifera.
Global distribution: Southern Europa, North and East Africa, Near East to Central Asia and China, India, Indonesia. New to Fuerteventura.
Tetragnathidae
Meta minima Denis, 1953
Determination. Wunderlich (1992).
Gran Canaria: Barranco Oscuro (Moya), 28.064128°N/ -15.594920AV, 830 m, 26.XII.2016, 1 ♀; Mina de Las Peñas (Valsequillo), 27.970742°N-15.529152°W, 1125 m, 29.VII.2017,2 ♀♀.
This species was found at the entrance of water mines.
Global distribution. Canary Islands. New to Gran Canaria.
Theridiidae
Simitidion lacuna Wunderlich, 1992
Determination. Nentwig et al. (2017).
Tenerife: Mesa Mota (Tegueste), 28.508157°N/-16.317333°W, 730 m, 21.I.2017, 1 juvenile; Camino de Jardina (San Cristóbal de La Laguna), 28.523834°N/ -16.284326°W, 22.IV.2017,1 ♀.
Two specimens were found beating Erica arborea.
Global distribution. Canary Islands, Spain, North Africa, Israel. New to Tenerife.
Steatoda latifasciata (Simon, 1873)
Determination. Nentwig et al. (2017).
Gran Canaria: Montaña de Tara (Telde), 28.003147°N/ -15.431478°W, 250 m, 27.XII.2016,2 ♀♀.
The collected specimens were found under rocks in a Euphorbia lamarckii scrub.
Global distribution. Canary Islands to Israel. New to Gran Canaria.
Theridion melanurum Hahn, 1831
Determination. Nentwig et al. (2017).
Gran Canaria: Tenteniguada (Valsequillo), 27.975834°N/ -15.528912°W, 980 m, 8.I.2017, 2 ♂♂; El Brezal (Santa María de Guía), 28.107158°N/-15.601551°W, 630 m, 07.IV.2017, 1♀.
Specimens in Tenteniguada were collected beating Pinus canariensis.
Global distribution. Europe to Siberia, Macaronesia, North Africa, Middle East. Introduced to USA. New to Gran Canaria.
A summary of the new records is provided in Table 1.
Discussion
Thirteen new island records as well as two new species records for the Canary arachnofauna have been detected, thus increasing the spider biodiversity of the archipelago to 515 species. Both Setaphis carmeli and Leptodrassus albidus are widely distributed along the Mediterranean basin. However, it is not possible for the author to conclude if these species were introduced, have colonized the Canary archipelago recently or have been overlooked in past surveys. A molecular phylogeographic study would be necessary to discern between those three main hypotheses. The spider assemblage in some habitats of the Canary Islands is still underestimated, it is the laurel forest areas where spider richness reaches its maximum; indeed, the two 50 × 50 m quadrats with higher richness are located in the laurel forests of Anaga in Tenerife (62 species) and Garajonay in La Gomera (70 species) (Gobierno de Canarias 2017). However, there are still many localities without any recorded species, especially in the eastern islands. Wunderlich (2011) claimed that the spider fauna of several unknown parts of the Canary Islands is not well studied and that an unknown number of species are still waiting for their discovery. Thus, arachnological studies should be developed in order to have a better knowledge of the real diversity and distribution of the Canary spider assemblage.
Acknowledgements
I would like to thank Javier García, Ruymán Cedrés and Yudith García for the material provided. I am very grateful to Dr. Pedro Oromí for his help during the elaboration of the manuscript. Also, I would like to thank Jørgen Lissner and an anonymous reviewer for their useful comments that improved the quality of the manuscript.
