Eukoenenia montagudi, Barranco, P. & Mayoral, J. G., 2014

Barranco, P. & Mayoral, J. G., 2014, New palpigrades (Arachnida, Eukoeneniidae) from the Iberian Peninsula, Zootaxa 3826 (3), pp. 544-562 : 553-556

Eukoenenia montagudi sp. nov.

( Figs. 24–35 , Table 1 )

Material examined. Holotype ♀, Cova Cirat, Montán, Castellón, Spain, [UTM 30TYK0733], 10 September 2005, leg. S. Montagud. Deposited in MNCN ( MNCN 20.02/17289).

Description of female. Prosoma: frontal organ with 2 rounded and granulated branches, 1.2 times longer than wide ( Fig. 24 ). Lateral organ with 7 pointed and granulate blades, each 3.5 times longer than wide (28/8 µm) ( Fig. 25 ). Propeltidium with 8 + 8 short setae. Metapeltidium with 3 + 3 setae (t1, t2, t3), t1 shorter than t2 and t3 (15 µm, 110 µm, 80 µm, respectively). Hand of chelicera with 6 dorsal and one ventral seta, each finger with 9 teeth. Sternum with 8 deuto-tritosternal setae in two irregular rows, posterior row with 6 setae and anterior with 2 ( Fig. 26 ).

Chaetotaxy of coxae: pedipalp with 13 setae; leg I with 12 setae; leg II with 12 setae, 8 normal + 4 thick; leg III with 12 setae, 8 normal + 4 thick; leg IV with 10 setae, 5 normal + 5 thick ( Figs. 27–31 ). Leg I: basitarsus 3, 3.2 times longer than wide, and bearing 3 setae ( Fig. 32 ); grt 80 µm, r 75 µm long; stiff seta about same length as segment (78/75 µm, t / r = 1.1), inserted in distal third and surpassing distal margin of basitarsus 4 (43/70 µm, s / er = 0.61). Ibta4 with one trichobothrium, six long, thin setae, one short seta and a forked seta at distal end. Leg IV: basitarsus 4 with 7 setae (2 esd, 2 esp, gla, grt and r) ( Fig. 33 ), bta / ti 1.11; stiff seta less than half length of dorsal margin (188/85 µm, t / r = 2.21) and inserted approximately in middle of segment (s / er = 0.58); esp inserted proximally and approximately ¼ from the base; grt and gla proximad of esp. Ta3 of pedipalp (Pta3) and ta3 of leg I (Ita3) with 3 bifurcate setae with symmetrical branches, arranged in line in distal third of segment.

Opisthosoma: Tergites II–VI each with 3 + 3 dorsal setae: t1, t3 (58 µm) and one slender lateral seta s (45 µm) on each half; tergites VII–VIII with 2 + 2 slender setae (t1, t3). Sternite III with 2 + 2 setae. Sternites IV–VIII each with 3 + 3 setae (a1, s1, s2.): inner ones (a1, 57 µm) longer than the others (s1, 42 µm; s2, 41 µm) ( Fig. 34 ). Segments IX–XI with 7, 8 and 6 setae, respectively.

Genital region of the female: With 2 pairs of lobes and a total of 31 setae. First lobe with 11 + 12 (1 asymmetrical on left side) setae in 6 transverse rows, 1 + 1, 1 + 1, 2 + 3, 2 + 2, 1+1 and 4 + 4 on border of lobe, of which a1 and a2 are shorter than a3 and a4. Second lobe with 4 + 4 setae, seta x short and thick, w very thin and inserted at each side of glandular orifices ( Fig. 35 ); genitalia with a group of 6 glandular orifices on each side.

Male. Unknown.

Etymology. The species is named after its collector, Sergio Montagud Alario.

Remarks. There are nine species of Eukoenenia with a chaetotaxy of 3+3 on sternites IV–VI: E. antanosa Remy, 1950 , E. bara Remy, 1950 , E. deceptrix Remy, 1959 , E. improvisa Condé, 1979 , E. lyrifer Condé, 1992 , E. pauli Condé, 1979 , E. remyi Condé, 1974 , E. thais Condé, 1988 and E. spelunca Souza & Ferreira, 2011 ( Condé 1974, 1979a, 1979b; 1988; Remy 1950; Souza & Ferreira 2011). Another species, E. necessaria Remy, 1959 , has 3+3, 4+4 and 4+4 setae, respectively, on these sternites ( Remy 1959).

The length of basitarsus IV in E. montagudi sp. nov. is 183 µm. None of the species mentioned above has a basitarsus IV over 130 µm (54–127.5) in length; in most of them it is around 100 µm or less. Remy (1950) did not report the number of setae on the propeltidium for the species from Madagascar, but the other six species ( E. improvisa , E. lyrifer , E. pauli , E. remyi , E. thais and E. spelunca ) carry 10+10 setae on the propeltidium. E. montagudi sp. nov. bears only 8+8 and this is remarkable considering that the 10+10 pattern is highly conserved in most species.

The shape of the genitalia in E. montagudi sp. nov. is distinctive in being short and rounded; it resembles that of E. deceptrix , E. necessaria , E. improvisa , E. lyrifer , E. pauli and E. remyi . This differentiates it from the other group of species (i.e. E. antanosa , E. bara and E. thai ) in which the female genitalia are prominent, pointed and triangular. The chaetotaxy of the first lobe of the genitalia is also distinctive: while E. montagudi sp. nov. carries 11 + 12 setae, E. deceptrix and E. necessaria carry 9+9. The morphology of the x and w setae on the second lobe is unique in the new species. Seta x is short, nude and located in a deeply internal position on the lobe, whereas in the other related species it is long, setulose and inserted closer to the external edge of the lobe. On the other hand, w is absent in all species with short and rounded genitalia, whereas it is still visible in E. montagudi as a very thin seta.

It is remarkable that only the European species of this group, E. remyi from Herzegovina, is similar to E. montagudi sp. nov. in the total length of the body (1400 vs. 1357 µm); all the other related species are much smaller (720–1070 µm) and are found in the tropics ( Brazil, French Guiana, Gabon, Madagascar and Thailand).

Figures

FIGURES 24 – 31. Eukoenenia montagudi sp. nov., holotype. 24, frontal organ, dorsal view; 25, lateral organ, dorsal view and lobe insertions; 26, deuto-tritosternal setae; 27, coxa I; 28, coxa III; 29, coxa II; 30, coxa IV; 31, pedipalp coxa. Thick coxal setae represented with a thicker line and a terminal spine. Scale bars: 24 – 26 = 50 µm; 27 – 31 = 100 µm.

FIGURES 32 – 35. Eukoenenia montagudi sp. nov., holotype. 32, basitarsi 3 – 4, leg I; 33, basitarsus, leg IV; 34, opisthosoma, ventral view; 35, female genital region. Scale bars: 32 – 33 = 100 µm; 34 = 200 µm; 35 = 50 µm.