Troglocaris (Spelaeocaris) neglecta, Sket & Zakšek, 2009

Sket, Boris & Zakšek, Valerija, 2009, European cave shrimp species (Decapoda: Caridea: Atyidae), redefined after a phylogenetic study; redefinition of some taxa, a new genus and four new Troglocaris species, Zoological Journal of the Linnean Society 155 (4), pp. 786-818 : 808-809

TROGLOCARIS (SPELAEOCARIS) NEGLECTA

SP. NOV. ( FIGS 11 Sne, 12)

Synonymy: Incl. S. pretneri from Orlovac tunnel, Cetina, Franjevic´, 2006.

Holotype (dissected) male: Croatia, Novigrad , Karišnica cave near Karin, ‘Spc-Karin-131m’.

Paratypes (dissected) females: As for holotype, ‘Spc- Karin-149f ’ and ‘Spc-Karin-150f ’.

Other material: Approximately ten specimens from the type locality; Sinj, Vrlika, Gospodska pećina (= Gospodarska pećina) cave, one specimen (partly dissected).

Etymology: In Latin neglectus means neglected, untidy, for the absence of grooming combs on pereopods V.

Diagnosis: A Spelaeocaris species with a very short rostrum, not serrated; male pleopod-I endopodite with a remarkable lobe at the AI basis; pereopods III–V

similarly shaped, not differentiated in mature males, dactyli III–V not comb-like.

Description of holotype male: A small and slender shrimp with reduced pigment and eyes; CL 5.7 mm. Rostrum indistinct, 5% of CL, and shorter than eye rudiments, without teeth. Pleonite VI twice as long as pleonite V and 55% of CL. Telson strongly tapering in distal direction, its width 45% of the length at the base, and 22% at the tip; 13 slender spines along the distal margin, only slightly different in lengths. Antenna-I article 1 longer than articles 2 + 3, with stylocerite narrow, distant, reaching 85% of article length; distal projection of article short and blunt, depressed. Antenna-II peduncle reaching the middle of the scaphocerite, which is moderately wide, almost 2.5 times as long as it is wide, with its pointed outer projection moderately long. Maxilla-I palp with one long, one short, and one very short seta. Maxilla-II scaphognathite rounded and with long setae distally. Maxilliped I with exopodital lobe wide, rounded, and slightly obliquely cut apically, the narrow flagellum as long as the width of the lobe. Length of pereopods II, III, and V: 80, 147, and 147% of CL, respectively. Exopodites on pereopods I–IV well developed, but exopodite on pereopod V missing. Chelae very thick, their basal (palmar) parts the same length as the fingers, with very prominent proximal bulges; carpus apically widened and excavated, in I much wider than in II. Carpus I shorter than its chela; pereopod II with the carpus as long as the chela. Pereopods III and V similarly shaped, with a line of widely spaced slender spines along propus inner edge; dactyli moderately wide, basal width 30% of length, with long nails, III with four and V with seven inner spines. Pleopod I with a smooth sympodite, endopodite plate-like, narrowly elliptical, extending medially into an AI, and with a lobe at its base. AI shorter than the half length of the lamina, its retinacle with approximately five hooks; lamina with ~12 long plumose setae along outer border and nine short setae along mesial margin, proximal ones are particularly short, thick, and doubled. Pleopod II with a few setae, some of them plumose, proximally. AM knife-shaped, pointed, with many small spines on the surface and along mesial border; AI longer than half AM, its retinacle with about 15 hooks. Uropod branches narrow, the tooth at the diaeresis spine indistinct.

Remarks: The pereopod-V dactylus, with its few inner spines that are not packed into a comb, is the most striking feature of this population. This appendage is similar only in Gallocaris inermis , but the molecular data place this new taxon as a clade of the Troglocaris (Spelaeocaris) subtree.

We identified the sample from Gospodska pećina at the springs of Cetina as T. (S.) neglecta sp. nov. from the low numbers of spines on the pereopod-V dactyli; in a much larger (than from Karišnica) female with a negligible rostrum, there are only ten spines on that dactylus.

Distribution: We found this species at the type locality and in Gospodska pećina (only female, not molecularly identified), which are both in Dalmacija, Croatia.

According to its hydrographic relationship with the Gospodska pećina population, as well as to its molecular distinction from S. pretneri from Vjetrenica ( Fig. 1 ), ‘S pelaeocaris pretneri ’ of Franjević (2006), from the Orlovac tunnel at Cetina in central Dalmacija ( Croatia) could also belong to this clade. So, this taxon might be more widespread in Dalmacija, Croatia.

Figures

Figure 1. Maximum-likelihood tree of the putative genus Troglocaris based on cytochrome oxidase subunit I (COI) + 16S rDNA sequences reconstructed under the GTR+I+G model of evolution. Numbers next to nodes represent bootstrap values of main splits, as percentages. Populations are named by locality names; ‘T’ indicates the type locality of a taxon. New taxonomic positions are indicated on the right. Atyaephyra and Typhlatya are used as the outgroups.

Figure 11. Spra, Troglocaris (Spelaeocaris) prasence sp. nov., holotype male from Obod cave. Sne, Troglocaris (Spelaeocaris) neglecta sp. nov., holotype male from Karišnica. Ska, Troglocaris (Spelaeocaris) kapelana sp. nov., holotype male from Obajdinova pećina. See the Appendix for a list of abbreviations. Scale bars: see Fig. 4: sE for all.