Corresponding author: Abdelhakim Mahi ( firstname.lastname@example.org )
Academic editor: Oana Moldovan
© 2017 Abdelhakim Mahi, Amina Taleb, Nouria Belaidi, Giuseppe Messana.
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: Mahi A, Taleb A, Belaidi N, Messana G (2017) Typhlocirolana longimera sp. n. (Crustacea, Isopoda, Cirolanidae) from north-western Algerian ground waters with notes on Algerian Typhlocirolana. Subterranean Biology 22: 27-41. https://doi.org/10.3897/subtbiol.22.11824
A new species of hypogean cirolanid isopod, Typhlocirolana longimera sp. n. is reported and described from a region located in north-western Algeria. Typhlocirolana longimera sp. n. can be distinguished from all other species of the genus especially by the peculiar shape of the merus of pereiopod I longer than in any other Typhlocirolana species, and for the presence of 6 molariform robust conical robust setae, the bottle shape of uropods and the aesthetasc formula of flagellum in antennulae. The presence in the same region of the two already known species T. fontis and T. gurneyi is also discussed.
Ground waters, Crustacea, Cirolanidae, Typhlocirolana, Algeria
The Cirolanidae is one of the most speciose isopod families, with more than 497 species belonging to 61 genera. Approximately 89 species in 26 genera are inhabiting subterranean waters (
One of the most interesting taxa of cirolanid isopods is the western Mediterranean stygobitic genus Typhlocirolana Racovitza, 1905. Widely spread in the area, it has colonized the continental groundwater of Sicily, Iberian Peninsula, Balearic Islands, Tunisia, Algeria and Morocco with several species (
During a survey of the subterranean waters of north-western Algeria, several specimens of the Typhlocirolana were collected from several wells of the region. Most of the specimens collected in one of the wells were attributed to the already described species T. fontis (Gurney 1902) and T. gurneyi Racovitza, 1912.
The aim of this paper is to describe a new species of the North African Typhlocirolana and comment on the presence of other Algerian species of the genus.
The specimens were collected (Fig.
Racovitza 1905: 74–76;
Holotype: 1♂, 9.8 mm wells in Ghazaouet, north–western Algeria, 35°04'34.53"N, 001°50'11.64"W; April 2011, A. Mahi legit, MZUF Coll. Crust. 4750. Paratypes: 3 ♂♂ and 4♀♀ (dissected and mounted on 40 slides), MZUF Coll. Crust. 4751; 38 ♂♂ and 129 ♀♀, MZUF Coll. Crust. 4752; 55♂♂ and 2 ♀♀, same locality and collector, coll. Mahi.
length between 9.8 mm and 10.9 mm.
length between 10.1 mm and 12.2 mm.
the specific name refers to the distinctive shape of the merus of pereopod 1. with its inner margin extending to half of propodite, and thus being longer than in any other species of Typhlocirolana.
A small–medium Typhlocirolana, epimera II–VII carinate, merus of I pereiopod long, depassing carpus and reaching 2/3 the length of propus, Penial processes about (1/4) length of pereonite 7. Pleotelson triangular, bearing 8–13 short simple setae on distal margin and 5–10 short simple sub-marginal setae (Fig.
Typhlocirolana longimera sp. n. Male. 10.9 mm. a habitus b lateral view c posterior margin of pleotelson d antenna e antennula f uropod. Scale: a, b = 1 mm; c–f = 0.1 mm.
Laminia frontalis (Fig.
Typhlocirolana longimera sp. n. a right mandible b incisor, left mandible c maxilla d maxillule e maxilliped f endite of maxilliped g frontal lamina. Scale: a–g = 0.1 mm.
Palp article 1 with 1 distal simple setae; article 2 with 16–20 setae (2–3 distal long simple setae, 2–4 basal simple setae, 11–13 medial barbed setae); article 3 with 9–11 barbed setae (the 3 last one are longest); article 3 shortest.
Pereiopod 1 (Fig.
Pereiopods 2–7 (Fig.
Pleopod 1 (Fig.
Typhlocirolana longimera sp. n. a pleopod 1 b pleopod 2 c female pleopod 2 d–f pleopods 3–5. Scale: a–f = 0.1 mm.
Pleopod 2 (Fig.
Pleopod 3 (Fig.
Pleopod 4 (Fig.
Pleopod 5 (Fig.
Typhlocirolana longimera is different from all other Typhlocirolana species described by the combination of the following characters:
– The peculiar shape of pereiopod 1 merus, which is longer than in any other species, depassing carpus and reaching the 2/3 length of propus.
– The presence of 6 molariform conical robust setae and 2 short strong robust setae usually 4 molariform robust setae;
– Propodus of pereiopod I with only 2 distal robust setae with accessory seta on internal margin, which is proximally crenulated and devoid of setae.
– The bottle shape of uropods;
– The chaetotaxy of pleopods1–5 more abundant.
Based on the general morphological aspect, as well as some characters, Typhlocirolana longimera sp. n. exhibits the greatest affinities with T. fontis and T. haouzensis Boutin, Boulanouar, Coineau & Messouli, 2002. However there is a mix of characters approaching T. longimera to several other Typhlocirolana species.
In addition to the main characters that make the difference with the other species of the genus Typhlocirolana, as cited above, T. longimera differs greatly from the others according to the aesthetasc formula of flagellum in antennulae: 122222222212 in T. buxtoni Racovitza, 1912, 12222212 in T. fontis, 12222212 in T. gurneyi, 121221 in T. ichkeuli Ghlala, Della Valle & Messana, 2009, 22210 in T. rifana Margalef, 1953.
Dentition and number of robust setae in propodus of pereopod I: in T. gurneyi not toothed with 2 or 3 short strong robust setae, in T. buxtoni not toothed with 3 strong robust setae, in T. fontis we don’t have information, in T. haouzensis not toothed with 3 medio distal robust setae, in T. ichkeuli not toothed with 3 robust setae.
Propodial organ is present in both male and female in T. longimera as well as T. buxtoni, but it is present only in the male in T. fontis, T. gurneyi, T. haouzensis and T. tiznitensis Boulal, Boulanouar & Boutin, 2009, while, it is absent in T. ichkeuli.
The basal palp article of the mandible in Algerian species (T. buxtoni, T. fontis and T. gurneyi) including T. longimera, exhibits a strong plumose seta. On the contrary this article is bare in Moroccan (T. haouzensis and T. tiznitensis) and in the Tunisian species T. ichkeuli.
Article III of the mandibular palp has 30 plumose setae in the Algerian species and only 13–16 in the Moroccan one. Whereas, T. longimera has an intermediate position with 9–11.
Pleopod 1 exopod of T. longimera with 28 or 29 distal setae in male and 28 to 36 in female is different to T. buxtoni (40), T. fontis (24 in male and 20 in female), T. gurneyi (27), T. haouzensis (23–26 in male and 27 in female), T. tiznitensis (26–30) and T. ichkeuli (24–26).
A complete transversal suture is present in pleopod 3, 4 and 5 in Moroccan (T. haouzensis and T. tiznitensis) and in the Tunisian species (T. ichkeuli), while it is present only in pleopod 4 and 5 in Algerian species (T. buxtoni, T. fontis and T. gurneyi) including T. longimera.
Uropod shape of T. longimera is similar to T. buxtoni, T. fontis, T. haouzensis and T. tiznitensis.
Distal margin of the pleotelson with plumose setae in Algerian species (T. buxtoni, T. fontis and T. gurneyi), versus simple setae in T. longimera such as Morroccan (T. haouzensis and T. tiznitensis) and Tunisian species (T. ichkeuli).
During several surveys in the years 2010–2013 many specimens of the taxon Typhlocirolana where collected in the wells of Ain Temouchent, SidiYouchaa and Ghazaouet, which do not belong to the new described species. In fact the examination of several specimens led us to consider that they are related to the two species described by
Ain Temouchent 8 ♂♂, 4 ♀♀, July 2012, A. Mahi legit, MZUF Coll. Crust. 4753.
The specimens of the Ain Temouchent region are most similar to T. gurneyi by the shape of uropod that is shallower, the pleotelson bearing 12 long plumose setae on the distal margin in male, 3 strong setae with additional setula on propodus of pereiopod 1 and the endite of maxilliped with 1–2 hooks and 3–4 plumose setae (Fig.
Sidna Youchaa 181 ♂♂, 138 ♀♀, Octobre 2010, A. Mahi legit; Ghazaouet, 32 ♂♂, 42 ♀♀, date, A. Mahi legit, MZUF Coll. Crust. 4754.
These specimens are most similar to T. fontis by the presence of propodial organ in male, endite of maxilliped with 1–2 hooks, chaetotaxy of pleopods 1 (19 plumose setae on exopod and 11 plumose setae on endopod of Ghazaouet collection; and 23 plumose setae on exopod and 14 plumose setae on endopod of Sidna Youcha) and pleopod 2 (21 plumose setae on exopod and 7 plumose setae on endopod of Ghazaouet collection; and 26 plumose setae on exopod and 6 plumose setae on endopod of Sidna Youcha) (Fig.
The first surveys of the underground aquatic fauna in Algeria run by
The history of Typhlocirolana evolution and colonization of subterranean waters, such as that of several other stygobitic crustaceans (
The Algerian situation is rather complicated and will need an accurate revision of the taxa both morphological and molecular. As has been pointed out by other authors (Nourisson 1956), many of the characteristics examined do not correspond to the descriptions that have been given or are common to several species.
This research and paper was supported by the PNE program of the Ministry of Higher Education and Scientific Research of Algeria. We are especially grateful to M. Boulanouar who provided precious help giving his advice on the study of other specimens of Typhlocirolana and to Dr. Nicole Coineau who critically revised the manuscript. G. Montesanto is gratefully acknowledged for his critical effort to teaching us the GIMP software for drawing.