Isotomodes tyrrhenicus, Fanciulli, Pietro Paolo, Dallai, Romano & Meneguz, Marco, 2015

Fanciulli, Pietro Paolo, Dallai, Romano & Meneguz, Marco, 2015, A new littoral interstitial species of the genus Isotomodes (Collembola, Isotomidae) from Italy, Zootaxa 3931 (2), pp. 293-297 : 293-297

publication ID

https://doi.org/ 10.11646/zootaxa.3931.2.9

publication LSID

lsid:zoobank.org:pub:8330F8A8-5F6C-4B3A-B785-F654E19F665A

DOI

https://doi.org/10.5281/zenodo.5658342

persistent identifier

https://treatment.plazi.org/id/EB02A56D-3C14-0C0D-209F-9FE5FE0FF871

treatment provided by

Plazi

scientific name

Isotomodes tyrrhenicus
status

sp. nov.

Isotomodes tyrrhenicus sp. nov.

Figs 1–3 View FIGURES 1 A – H View FIGURES 3 A – E , Tab. 1 View TABLE 1

Type locality. Specimens of the new species were collected in the littoral sand dune of the regional park of S. Rossore (Tuscany) (43°47’12.5’’N, 10°16’09.7’’).

Type material. Holotype (female) and 10 paratypes (7 females and 3 males). All types deposited in the Collembola collection of the Department of Life Sciences, University of Siena.

Description. Length of holotype and paratypes about 0.6-0.7 mm. Eyes and body pigment absent, cuticle granulation fine and regularly distributed. Antennae longer than the cephalic diagonal (A/d = 1.2). Ant. I with 12 setae, one dorsal microseta and two ventral sensilla of different length ( Fig. 1A View FIGURES 1 A – H ); Ant. II with 14 setae, three basal microsetae and one ventral sensillum ( Fig. 1A View FIGURES 1 A – H ). Ant. III with 20-23 setae; Ant. III sensory organ formed by two globular sensilla placed in two cuticular pits, two curved and subcylindrical guard sensilla and one ventrolateral thinner sensillum ( Fig. 1A View FIGURES 1 A – H ). Ant. IV with about 15 subcylindrical dorsal sensilla and several ordinary setae ( Fig. 1A View FIGURES 1 A – H , 3B View FIGURES 3 A – E ); subapical organite and microsensillum present ( Fig. 1B View FIGURES 1 A – H ). Basomedial field (submentum) with 4 +4 setae, basolateral field (mentum) with 5 setae ( Fig. 1F View FIGURES 1 A – H ). Labial palp with four papillae (A, B, D, E) with 1, 2, 2, 2 guard setae respectively. Lateral process of labial palp thicker, similar to basal papilla with a blunt roundish apex ( Fig. 1H View FIGURES 1 A – H ). Labrum with 3/4,4,4 setae ( Fig. 3C View FIGURES 3 A – E ). PAO elliptical, slightly narrower than the base of the antenna with six posterior setae ( Fig. 1C View FIGURES 1 A – H , 3E View FIGURES 3 A – E ). Tibiotarsi I, II and III with 21, 21 and 21–22 acuminate setae respectively (Fig. 2E). Claw without internal teeth, empodium lanceolate half as long as the claw. Head with 5+5 setae along the ventral line (Fig. 2C); thoracic sternites I, II and III with 2, 2 and 4 setae (Fig. 2C) FIGURES 2A–F. Isotomodes tyrrhenicus sp. nov.: A, dorsal chaetotaxy; B, distribution of macrosetae (M), accp sensilla (accessory to the p row), lateral sensilla (al) and microsensilla (ms); C, ventral chaetotaxy; D, chaetotaxy of the head showing the five unequal dorsomedial setae (eg. A0); E, chaetotaxy of leg III; F, chaetotaxy of abdominal segmants IV–VI.

VT with 5 + 5 distal setae and 2 +2 proximal setae ( Fig. 1G View FIGURES 1 A – H , 3D View FIGURES 3 A – E ). Furca well developed, manubrium longer than dens with 10-11 +10-11 posterior setae; dens with 2 posterior setae of different lengths and 4 anterior setae; mucro bidentate ( Fig. 1E View FIGURES 1 A – H , 3A View FIGURES 3 A – E ). Retinaculum with 3 teeth and one seta on the body. Female genital opening with 2+2 setae on anterior and 1+1 on posterior valve, male genital opening as shown in Fig. 1D View FIGURES 1 A – H . Dorsal and ventral body chaetotaxy as in Fig. 2 A and 2C; head with five unequal dorsomedial setae including A0 (Fig. 2D). Axial dorsal chaetotaxy of the thorax and abdomen as follows: 7,6 / 4,4,5. Dorsal macrochaetotaxy: 1,1 / 3,3,3,2+2; sensillar chaetotaxy (accp): 1,1 / 2,2,2,1. Lateral sensilla: 3,2 / 0 0 0 0 (Fig. 2B). Abd. V + VI with one ventro lateral sensillum close to the setae P5 and P6 (Fig. 2F). There are 10 setae between the macrosetae S1 and 2 between macrosetae S2. 5 microsetae m present. The posterior row of setae on the abdominal segment IV includes 25 setae between lateral accp sensilla, one of them unequal (P0) and the others as 5 thick setae (P1, P3, P5, P6, P10) and 7 thin setae (P2, P4, P7, P8, P9, P11, P12) (Fig. 2F). Abd. tergite V with 4 +4 thin setae (one of them longer than the others), 2 long dorsal macrosetae and 1 +1 microsensilla. Chaetotaxy of abdominal segment VI consists of some spine-like and slightly barbulate setae (P0, P1, P3, P4) while the others are long, thin and smooth setae (P2, P5 and P6).

Remarks. The new species is closely related to Isotomodes alavensis Simón, Luciáñez, Ruiz & Martin, 1994 from which it can be separated by the different number of setae on the ventral tube (4+ 4 in I. alavensis against 5+ 5 in I. thyrrenicus sp. nov.). Further differences are in the type of setae on the VI abdominal tergites (P4 spine-like and slightly barbulate in I. thyrrenicus sp. nov., ordinary seta in I. alavensis ); moreover I. thyrrenicus sp. nov. has P12 on Abd. IV while it is absent in I. alavensis . Others 5 species of Isotomodes have 5+5 distal setae on the ventral tube as I. thyrrenicus sp. nov. but they can be distinguished by the different chaetotaxy of dens ( Tab. 1 View TABLE 1 ): I. thyrrenicus sp. nov. (dens anterior setae= 4; posterior= 2), I. gisini Gama, 1963 (ant.= 2; post.= 2), I. maroccanus Stach, 1947 (ant.= 1; post.= 2), I. productus ( Axelson, 1906) (ant.= 1; post.= 2), I. sexsetosus Gama, 1963 (ant.= 6; post.=2) and I. sotoensis Simon et al 1994 (ant.= 5; post.=2).

Etymology. The name of the new species refers to the Tyrrhenian Sea that is just in front of the beach in which it was found.

Arbea, I.J. (2006) The genus Isotomodes Linnaniemi, 1907 of the Ibero-balearic fauna, with description of two new species (Collembola: Entomobryomorpha: Isotomidae). Zootaxa, 1351, 45 –52.

Abrantes, E.A. & Mendonça, M.C. (2007) New specie and a new record of Isotomidae (Collembola) from the coast of Brazil. Zootaxa, 1500, 55 –60.

Axelson, W.M. (1906) Beitrag zur Kenntnis der Apterygotenfauna in der Umgebung Revals. Acta Soc. Fauna Flora Fennica, 28, 2 –22.

Bellinger, P.F., Christiansen, K.A. & Janssens, F. (1996–2014) Checklist of the Collembola of the World. Available from: http:// www.collembola.org Last updated on 2014. 0 3 .31 by Frans Janssens) (date of access April 2014)

Dallai, R., Cicconardi, F. & Fanciulli, P.P. (2010) Insecta Collembola. In: Relini, G. (Ed.), Checklist della flora e della fauna dei mari italiani (Parte II). Biologia Marina Mediterranea, 17, 538–544.

Gama, M.M. da (1963) Monografia do género Isotomodes. Memórias e Estudos do Museu Zoologico da Universidade de Coimbra, 284, 1 –44.

Fjellberg, A. (1999) The labial palp in Collembola. Zoologischer Anzeiger, 237, 309–330.

Potapov, M. (2001) Isotomidae. In: Dunger, W. (Ed.), Synopses on Paleartic Collembola. Vo l. 3. Abdhandlungen und Berichte des Naturkundemuseums Görlitz, 73 (2), 1–603.

Simon, J.C., Luciáñez, M.J., Ruiz, M. & Martín, J. (1994) Tres nuevas especies de Isotomodes Axelson (Linnaniemi) 1907 (Insecta, Collembola) de la Peninsula Ibérica. Graellsia, 50, 101–108.

Stach, J. (1947) The Apterygotan Fauna of Poland in Relation to the World-Fauna of this Group of Insects. Family: Isotomidae. Polska Akademia Umiejętności, Acta monographica Musei Historiae Naturalis, Kraków, 488 pp.

Thibaud, J.M. (2007) Recent advances and synthesis in biodiversity and biogeography of arenicolous Collembola. Annales de la Societé Entomologique de France, 43, 181–185.

Thibaud, J-M. (2008) Les collemboles des sables littoraux de Madagascar. Annales de la Societé Entomologique de France, 44, 503–519.

Thibaud, J-M. & Christian, E. (1997) Biodiversity of interstitioal Collembola (Insecta) in sand sediments. European Journal of Soil Biology, 33, 123–127.

TABLE 1. Characters comparison between I. thyrrenicus sp. nov. and some closely related species. * SSLM = smooth spin like macroseta, BSLM = barbulated spin like macrosetae; ** a = spiniform slightly barbulate; b = ordinary setae.

Species number of laterodistal setae on VT number of setae on posterior margin of PAO number of anterior setae on dens presence/ absence of p12 seta on Abd. IV presence/absence and shape of macroseta on Abd. V* Shape of P setae on Abd. VI**
I. thyrrenicus sp. nov. 5+5 6 4 present 1+1 SSLM a=P0,P1,P3,P4; b=P2,P5,P6
I. alavensis 4+4 6-7 4 absent 1+1 SSLM a=P0,P1,P3; b=P2,P4,P5,P6
I. gisini 5+5 5 2 absent 0+0 b=P0,P1,P2,P3,P4,P5,P6
I. marroccanus 5+5 6 1 present 0+0 b=P0,P1,P2,P3,P4,P5,P6
I. productus 5+5 7 1 present 1+1 SSLM b=P0,P1,P2,P3,P4,P5,P6
I. sexsetosus 5+5 6 6 absent 0+0 b=P0,P1,P2,P3,P4,P5,P6
I. sotoensis 5+5 6-7 5 absent 1+1 BSLM a=P1,P3; b P0,P2,P4,P5,P6
References            

Kingdom

Animalia

Phylum

Arthropoda

Class

Entognatha

Order

Collembola

Family

Isotomidae

Genus

Isotomodes

GBIF Dataset (for parent article) Darwin Core Archive (for parent article) View in SIBiLS Plain XML RDF