Tyrrhenoleuctra antoninoi, Fochetti, Romolo & Figueroa, José Manuel Tierno De, 2009

Fochetti, Romolo & Figueroa, José Manuel Tierno De, 2009, A new species of Leuctridae discovered by means of molecular and biochemical approaches: Tyrrhenoleuctra antoninoi n. sp. (Insecta: Plecoptera), Zootaxa 2112, pp. 41-46 : 42-45

Tyrrhenoleuctra antoninoi sp. n. Fochetti & Tierno de Figueroa

Fig. 2 A-D.

Type Material: Holotype: Spain, Balearic Islands, Mallorca Island, San Miguel brooklet, Coves di Companet, m 20, 39º 47’ 48’’ N, 02º 57’ 96’’ E, 30-III-1999, 1 male, Fochetti & Sezzi leg. Paratypes: same locality and date, 6 males and 4 females, Fochetti & Sezzi leg.

Other material examined: Spain, Balearic Islands, Mallorca Island, Son Alzines, Alqueda stream, m 500-540, 30-III-1999, 3 nymphs, 18 males and 35 females.

The holotype and paratypes are deposited in the Museo di Zoologia del Dipartimento di Biologia Animale e dell’Uomo della Università di Roma «La Sapienza» ( Italy). Since specimens from the type population do not show individual molecular variation (Fochetti et al. 2008) we sequenced a paratype, in order not to damage the holotype. The accession numbers of the COI and 12S sequences (European Molecular Biology Laboratory ( EMBL) Nucleotide Sequence Database) of this specimen are respectively FM213091 and FM212943 .

Other material referred: Spain, Mallorca: Torrente de Comafreda, m 620, 1-II-1988, 19-V-1988; Torrente de Alqueda or de Manut, m 500, 1-II-1988, 19-V-1988; Torrente de Ternelles, m 80, 1-II-1988; Torrente de Son Vivot or de Massanella, m 60, 2-II-1988; Torrente de Almendrà, m 360, 2-II-1988; Torrente Sa Riera, m 160, 3-II-1988; Torrente Sa Riera, m 220, 21-V-1988; tributary of Embalse de Gorg Blau, m 640, 6-II-1988, 22-V-1988; brooklet close to Ermita de Betlem, m 240, 20-II-1988, 17-V-1988; Torrente de Ses Torretes, m 100, 20-II-1988; Torrente de Es Gorg des Diners, 21-II-1988, 20-V-1988; brooklet close to Major en Sa Granja, m 380, 25-II-1988; brooklet "Mal Torret de Massana", m 60, 26-II-1988; Torrente de Sant Miquel, m 20, 26-II-1988, 18-V-1988; (subnom. Tyrrhenoleuctra minuta ) ( García Avilés, 1990). Menorca: Torrente de Cala Mesquida, XII-1982, 18-XI-1984, 19-I-1985, 5-I-1986, 12-I-1986, 19-I-1986, 22-I-1986, 1- II-1986, 19-II-1986, 27-II-1983, 5-I-1986, 1-III-1986; (subnom. Tyrrhenoleuctra sp.) ( Pons, 1986). Torrente de Binimel-là, m 10, 3-III-1988; Torrente de Son Boter, m 10, 17-VI-1986; (subnom. Tyrrhenoleuctra minuta ) ( García Avilés, 1990).

We tentatively refer to the new species the following material contained in P. Zwick’s collection (Schlitz, Germany: Zwick, in litteris): Mallorca: Est from Puig Punyent, m 200, 12.V.1978, 15.V.1978, 17.V.1978, 30.V.1978; southern slope of Puig Mayor, m 700, Soller, 7/ 9.V.1978, 16.V.1978, 25/ 29.V.1978; South from Lluch, m 520, 15.V.1978, Malicky leg.

Diagnosis: Despite the clear-cut molecular differentiation, this species does not show evident diagnostic morphological features. In fact, the use of traditional morphological characters in the species taxonomy of Tyrrhenoleuctra is severely limited by the strong intraspecific variation of these features. For instance, in some populations variation of both the male epiproct and female genital plate overlap the entire range observed in the genus (Fochetti et al. 2008). Hereafter, a brief description of the morphological pattern of the new taxon is given:

A Tyrrhenoleuctra of variable size (male: 3.5-4.5 mm; female: 5-6.5 mm). General brown colour, legs uniformly brown. Tergites and sternites I-VIII clearly divided. Ninth segment with tergite and sternite fused. Male approximately 2/3 of female size. Male ninth sternite with a round vesicle ( Fig. 2 A). Apical part of the epiproct more or less triangularly shaped in lateral view ( Fig. 2 B). Male paraprocts with a sclerotized basal band enlarging on both sides ( Fig. 2 A). Cerci simple ( Fig. 2 A-D).

As regards the molecular characters, the combined aligned dataset of all analyzed Tyrrhenoleuctra comprised 1660 nucleotide positions (12S rRNA: 344; COI: 1316). Of these, 1149 positions were constant, 282 (219, excluding gaps) variable positions were parsimony-uninformative and 229 (227, excluding gaps) variable positions were parsimony-informative. A pairwise distance calculation (MEGA 4.1; Kumar et al.

2008) using the COI sequence data ( Table 1; sequence data not shown, available on request from first author) shows that T. antoninoi is on average more than 10% distant from the other species. Genetic variation of intraspecific populations ranged from 0.002 to 0.011 with populations of T. zavattarii and from 0.000 to 0.020 and 0.010 for populations of T. tangerina and Tyrrhenoleuctra sp. C, respectively.

1 2 3 4 5 6 7 8 9 10 11 1

2 0.247

3 0.237 0.102

4 0.241 0.103 0.011

5 0.239 0.117 0.113 0.120

6 0.237 0.101 0.010 0.008 0.116

7 0.244 0.115 0.113 0.119 0.010 0.115

8 0.245 0.103 0.011 0.002 0.121 0.011 0.120

9 0.249 0.118 0.096 0.101 0.107 0.099 0.110 0.099

10 0.266 0.141 0.151 0.158 0.131 0.157 0.130 0.155 0.146 11 0.246 0.109 0.092 0.095 0.104 0.093 0.107 0.093 0.020 0.143 12 0.246 0.109 0.092 0.095 0.104 0.093 0.107 0.093 0.020 0.143 0.000 Male holotype: Total length: 4.8 mm. Forewing: 5.5 mm, hindwing: 4.5 mm. General colour brown. Antennae and legs uniformly brown. Epiproct pear-shaped in lateral view, triangularly-shaped in rear view.

Female: Distal edge of the genital plate of variable shape, rounded or more or less triangular according to the maturity or stage (probably mated vs. unmated).

Etymology: the species is named after our friend and colleague Antonino Sánchez-Ortega (Granada- Spain), who died prematurely but greatly contributed to Plecoptera research on the Iberian Peninsula.

Affinities and remarks: The morphological characters of T. antoninoi sp. n. are quite variable. Hence, T. antoninoi sp. n. is almost indistinguishable on sole morphological grounds from other known Tyrrhenoleuctra species. According to biochemical markers ( Fochetti et al., 2004), T. antoninoi sp. n. is more closely related to Southern Iberian Tyrrhenoleuctra species rather than to the Corso-Sardinian one. This phylogenetic pattern is confirmed by the molecular approach of Fochetti et al. (2008) that made evident an Ibero-Maghrebian clade within the genus and disrupted the currently accepted taxonomic arrangement of this genus. With regards to morphological pattern, T. antoninoi sp. n. is more similar to the Sardo-Corsican T. zavattarii in having a less marked wing polymorphism with respect to the continental Iberian species, although factors controlling wing polymorphism are poorly understood.

T. antoninoi sp. n. is a typical temporary running water inhabitant from middle to very low altitude streams (m 10-640), a habitat prone to marked environmental fluctuations. It has been postulated that environmental factors and food availability can influence morphological features in Leuctridae , due to their range of phenotypic plasticity ( Lillehammer, 1976).

As stated by Fochetti et al. (2008), Tyrrhenoleuctra is an example of a taxon where molecular tools are required to depict the true species richness and to define phylogenetic history.

Figures

FIGURE 2. General morphological pattern of Tyrrhenoleuctra sp. Tip of the male abdomen in dorsal view (A), lateral view (B) and ventral view (C), tip of female abdomen in ventral view (D) (redrawn from Fochetti & Tierno de Figueroa 2008).