Cordioniscus lusitanicus Reboleira & Taiti, 2015

Reboleira, Ana Sofia P. S., Gonçalves, Fernando, Oromí, Pedro & Taiti, Stefano, 2015, The cavernicolous Oniscidea (Crustacea: Isopoda) of Portugal, European Journal of Taxonomy 161, pp. 1-61 : 35-39

Cordioniscus lusitanicus Reboleira & Taiti sp. nov.

urn:lsid:zoobank.org:act:B1F2D756-D90F-43BF-9F42-4F8EAE6C79F0

Figs 23 A–G, 24A–E, 25A–E

Diagnosis

A blind species of Cordioniscus characterised by a colourless body, the male pereopod 7 ischium having a rounded hyaline basal lobe, the triangular male pleopod 1 exopod, as long as the endopod, and the complex apical part of the male pleopod 2 endopod.

Etymology

From Latin lusitanicus = Portuguese. The name refers to the country where the specimens were collected.

Material examined

Holotype

PORTUGAL: ♂, Algar de Santo António , Estremoz-Cano Massif, 30 Mar. 2009 ( MZUF).

Paratypes

PORTUGAL: 1 ♂, 7 ♀♀, same data as holotype, 30 Mar. 2009 ( MZUF); 2 ♂♂, 1 ♀, Gruta de Ibne Ammar, Algarve Massif, 23 May 2009 ( MZUF); 3 ♂♂, same locality and date ( SR); 3 ♀♀, Algarão do Remexido, Algarve Massif, 5 Sep. 2009 ( SR); 1 ♂, same locality, 30 Jan. 2009 ( MZUF); 2 ♀♀, same locality, 29 Dec. 2009 ( SR); 1 ♂ juv., 2 ♀♀, Gruta da Senhora, Algarve Massif, 3 Jul. 2011 ( ZMUC); 1 ♂, same locality, 18 May 2013 ( SR).

Description

Maximum size: ♂ 5.0 ×1.0 mm; ♀ 3.0× 0.8 mm. Body colourless and elongated ( Fig. 23A ). Dorsum of cephalon and pereon finely granulated and equipped with triangular scale-setae ( Fig. 23B ); pleon and telson smooth. Cephalon ( Fig. 23 C–D) with short, rounded frontal lateral lobes. Eyes absent. Pereonites 1–3 with rounded posterior corners; pereonites 4–7 with epimera pointing backwards ( Fig. 23A ). Pleon ( Fig. 23A, E ) narrower than pereon; pleonites 3–5 with epimera reduced and no posterior points. Telson ( Fig. 23E ) about twice as wide as long, distal part with concave sides and broadly rounded apex. Antennula ( Fig. 23F ) with third article longer than first and second articles, with small triangular posterior point, and with one subapical and four apical, long aesthetascs. Antenna ( Fig. 23G ) with articles of peduncle bearing scale-setae; fifth article distinctly longer than flagellum; flagellum with four articles, with very long apical organ. Right mandible ( Fig. 24A ) with one penicil between lacinia mobilis and molar process, which bears long penicil; left mandible ( Fig. 24A ) with two penicils. Maxillula ( Fig. 24C ) inner branch bearing two thickset penicils at apex and long subapical penicil; outer branch with 10 teeth and thin, setose stem among outer group of teeth. Maxilla ( Fig. 24D ) apically bilobed and setose, with outer and inner lobes subequal; inner lobe with several long, stout setae along margin. Maxilliped ( Fig. 24E ) basis enlarged in middle; endite triangular, with stout triangular penicil at apex; palp distally rounded, with long setae at apex, and basal article with two short compound setae. Uropod ( Fig. 23E ) with exopod distinctly longer than endopod, endopod inserted proximally to exopod.

MALE. Pereopod 1 ( Fig. 25A ) with no particular modifications. Pereopod 7 ( Fig. 25B ) ischium with slightly convex sternal margin and bearing rounded hyaline lobe at base. Genital papilla ( Fig. 25C ) lanceolate with pointed apex, shorter than pleopod 1. Pleopod 1 ( Fig. 25D ) exopod triangular, as long as endopod; endopod with short triangular basal article and flagelliform distal article. Pleopod 2 ( Fig. 25E )

exopod small, ovoidal; endopod biarticulated, distal article thickset, about three times as long as basal article, with parallel sides and complex apical part.

Remarks

At present the genus Cordioniscus includes with certainty 14 species ( Andreev 2002; Schmalfuss 2003), mainly distributed in caves of Mediterranean countries. For a definition of the genus see Schmalfuss & Erhard (1998). Species of Cordioniscus are mainly distinguishable by the shape of the male pleopod 2 endopod. In the Iberian Peninsula, only Cordioniscus stebbingi (Patience, 1907) was previously known from some caves in Valencia and Castellón provinces, Spain ( Vandel 1952b). The new species differs from C. stebbingi in the lower number of aesthetascs on the antennula (5 vs 8), the presence of a hyaline lobe on the male pereopod 7 ischium, and the thickset and complex, rather than tapering, distal part of the male pleopod 2 endopod. In the presence of a lobe at the base of the male pereopod 7 ischium, C. lusitanus Reboleira & Taiti sp. nov. is similar to C. bulgaricus Andreev, 1986 from Bulgaria and C. andreevi Schmalfuss & Erhard, 1998 , C. beroni Vandel, 1968 , C. graecus Vandel, 1959 and C. kithnosi Andreev, 1986 from Greece ( Vandel 1959, 1968; Andreev 1986 a, 1986 b; Schmalfuss & Erhard 1998). It differs from all these species in the different structure of the male pleopod 2 endopod.

Ecological notes

This species was collected in two isolated karst areas, Alentejo and Algarve. These two areas are more than 200 km apart and are separated by the extended dry, flat areas of Alentejo Province. In the Algarve Massif this species is frequent in caves. In the northern locality, Algar de Santo António in Alentejo, the specimens were collected in deep layers of soil at the bottom of the first pit (– 20 m), where it cohabits with the troglobiotic millipede Sireuma nobile Reboleira & Enghoff, 2014 ( Reboleira & Enghoff 2014 b).

Figures

Fig. 23. Cordioniscus lusitanicus Reboleira & Taiti sp. nov. from Algar de Santo António, Estremoz- Cano. — Paratype, ♀. A. Adult specimen in dorsal view. — Paratype, ♂. B. Dorsal scale-seta. C. Cephalon in frontal view. D. Cephalon in dorsal view. E. Pleonites 4, 5, telson and uropods. F. Antennula. G. Antenna.

Fig. 24. Cordioniscus lusitanicus Reboleira & Taiti sp. nov. from Algar de Santo António, Estremoz- Cano, paratype, ♀. A. Right mandible. B. Left mandible. C. Maxillula. D. Maxilla. E. Maxilliped.

Fig. 25. Cordioniscus lusitanicus Reboleira & Taiti sp. nov. from Algar de Santo António, Estremoz- Cano, paratype, ♂. A. Pereopod 1. B. Pereopod 7. C. Genital papilla. D. Pleopod 1. E. Pleopod 2.