Research Article |
Corresponding author: Lluc Garcia ( llucgarciaisopoda@gmail.com ) Academic editor: Stefano Taiti
© 2020 Lluc Garcia, Adrià Miralles-Núñez, Toni Pérez-Fernández.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Garcia L, Miralles-Núñez A, Pérez-Fernández T (2020) First record of the genus Graeconiscus Strouhal, 1940 (Isopoda, Oniscidea, Trichoniscidae) in the Iberian Peninsula with the description of a new troglobitic species. Subterranean Biology 36: 51-61. https://doi.org/10.3897/subtbiol.36.58272
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Graeconiscus gevi sp. nov., a new troglobitic terrestrial isopod (family Trichoniscidae, subfamily Haplophthalminae), is described. The specimens of the new species are found in the Cueva del Yeso III, in the province of Málaga (SE Spain). Graeconiscus gevi sp. nov. is closely related to Graeconiscus thermophilus (Çaglar, 1948), an oculate species from Turkey and some Eastern Mediterranean islands. The morphological differences between both species are discussed and illustrated by SEM images of specimens from Málaga and Cyprus. The studied material represents the first record of the genus Graeconiscus in the Iberian Peninsula.
Iberian Peninsula, cave biodiversity, terrestrial isopods, Haplophthalminae, new species
Within the family Trichoniscidae, the subfamily Haplophthalminae is characterized by presenting, among other characters, a complex tergal ornamentation that contrasts with a remarkable homogeneity in its sexual characters. For this reason its classification has been based generally on body ornamentation (see
So far, 14 species of Haplophthalminae belonging to the genera Balearonethes, Haplophthalmus, Iberoniscus and Moserius have been recorded in the Iberian Peninsula and the Balearic Islands (
In the framework of biospeleological studies which have been carried out in the south and southeast of the Iberian Peninsula, several specimens have been collected. Based on their morphological characters, we include them in the genus Graeconiscus Strouhal, 1940, known so far from the eastern Mediterranean islands, continental Greece, North Macedonia and western Turkey (
The specimens collected from a cave in the province of Málaga, due to their specific combination of morphological features, have been included in a new species, Graeconiscus gevi sp. nov., which is described and fully illustrated in this article. It is also proposed to include the specimens recorded in Morocco by
Several specimens have been dissected under a stereomicroscope (Euromex NZ). For its morphological study, appendages, mouthparts and tergites have been mounted in micropreparations using glycerin or Faure liquor as appropriate, after treatment in some cases with Amann’s lactophenol. The drawings have been made using a camera lucida attached to an optical microscope (Olympus CH30). The tergal structure of one specimen has been analyzed under a scanning electron microscope (Hitachi S-3400N). The final illustrations were prepared according to the method described by
The Cueva del Yeso III (Fig.
MNCN: National Museum of Natural Sciences-Museo Nacional de Ciencias Naturales, Madrid, Spain. MBCN: Balearic Museum of Natural Sciences-Museu Balear de Ciències Naturals, Sóller, Mallorca, Spain. CLLG: Lluc Garcia personal collection, Sóller, Mallorca, Spain.
Family Trichoniscidae Sars 1989
Subfamily Haplophthalminae Verhoeff, 1908
Graeconiscus thermophilus. –
Derived from G.E.V., the acronym in Spanish of the Villacarrillo Speleological Group, for its great contribution to the knowledge of the subterranean biodiversity of the Andalusian region.
Holotype. Spain • 1 male; Málaga, Antequera, Cueva del Yeso III; ETRS89 UTM 30S 345702 4094826, 441 m a.s.l.; 27 Apr. 2008; Toni Pérez-Fernández leg.; MNCN 20.04/12093. Paratypes. Spain • 3 males, same data as holotype; MNCN 20.04/12094, MNCN 20.04/12095, MNCN 20.04/12096. 4 females, same data as holotype; MNCN 20.04/12097, MNCN 20.04/12098, MNCN 20.04/12099, MNCN 20.04/12100. 1 male, 3 females, same data as holotype; CLLG 153. 1 male, 2 females, same locality as holotype, 26 Sep. 2009; Toni Pérez-Fernández leg.; CLLG 185. 1 male, 3 females, same locality as holotype; 28 Sep. 2008; Toni Pérez-Fernández leg.; CLLG 183. 1 male, 2 females, same locality as holotype; 29 Mar. 2008, Toni Pérez-Fernández leg.; CLLG 144.
Spain • 7 damaged specimens; same locality as holotype; 24 Oct 2009; Toni Pérez-Fernández leg.; MBCN 23370.
Graeconiscus thermophilus. Cyprus • 5 males, 3 females; Loutra Afroditis; 4 Feb. 2020; Spyros Sfenthourakis leg.; CLLG 582.
A blind and unpigmented species of Graeconiscus. Head with central anterior tubercle bilobed; posterior row of tubercles with the central ones almost fused. Pereon-tergites 1–6 with four individualized rounded, swollen, tubercles (2+2) not reaching the pereonites hind margin. Seventh pereonite with two large paramedian rounded, swollen, tubercles not reaching the hind margin. Pleonite 3 with a single, large and swollen, transversal tubercle.
Maximum size observed: 3.2 mm (female), 3 mm (male). Body unpigmented. Eyes absent. Contour regularly ovoid, without interruption between pereon and pleon (Figs
Male: Pereopod 1 (Fig.
This new species is included in the genus Graeconiscus Strouhal, 1940 due to its tergal ornamentation, which is characterized by two transversal rows of tubercles on the cephalon, 2+2 tubercles on the pereon-tergites 1–6, two paramedian tubercles on the seventh pereonite and a single central tubercle on the third pleonite (
Graeconiscus gevi sp. nov. is morphologically closely related to G. thermophilus, which was initially included in the genus Haplophthalmus (Çaglar, 1948), and redescribed by
The examined specimens of G. gevi sp. nov. are almost identical to those described, and fully illustrated, by
The genus Graeconiscus was so far unknown in the Iberian Peninsula. Its presence in localities of the western Mediterranean (north Morocco and southeast Spain), contrasts with its apparent cantonment in southeastern Europe, some eastern Mediterranean islands and the Marmara region of Turkey.
Graeconiscus gevi sp. nov., male paratype A dorsal view B cephalon, dorsal C last pereonite, pleon and pleotelson, dorsal D last pereonites, pleon and pleotelson, lateral view (arrow points the tubercle of third pleon-tergite) E–G Graeconiscus thermophilus, male specimen from Cyprus E dorsal view F last pereonites, pleon and pleotelson G last pereonite, pleon and pleotelson, lateral view (arrow points the tubercle of third pleon-tergite) H tegumentary basal structure (left G. gevi sp. nov.; right, G. thermophilus).
The authors thank Spyros Sfenthourakis for collecting and sending specimens of Graeconiscus thermophilus from Cyprus. They also thank Stefano Taiti for his comments and suggestions to the first version of this description. We also thanks Frederick Price and Guillermo García-Saúco the help in editing the final text. Thanks also to Ferran Hierro-Riu, (Scientific-technical services, University of Balearic Islands), for taking the photographs with the scanning electron microscope.