Eukoenenia magna, Souza & Ferreira, 2020

Souza, Maysa Fernanda Villela Rezende & Ferreira, Rodrigo Lopes, 2020, Three new cave-dwelling Eukoenenia (Palpigradi: Eukoeneniidae) from limestone caves in Northern Minas Gerais state, Brazil, Zootaxa 4808 (2), pp. 251-283 : 253-256

publication ID	https://doi.org/ 10.11646/zootaxa.4808.2.2
publication LSID	lsid:zoobank.org:pub:DDE14D7E-31AA-4B0A-B096-0B9382FF3E0E
persistent identifier	https://treatment.plazi.org/id/58E969E6-45D8-40C7-AEA2-B1E960E78DCA
taxon LSID	lsid:zoobank.org:act:58E969E6-45D8-40C7-AEA2-B1E960E78DCA
treatment provided by	Plazi
scientific name	Eukoenenia magna
status	sp. nov.

Treatment

Eukoenenia magna sp. nov.

( Figs. 2–9 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 View FIGURE 9 , Tables 1–3)

urn:lsid:zoobank.org:act:58E969E6-45D8-40C7-AEA2-B1E960E78DCA

Material examined. Holotype: ♂ ( ISLA 13169): Brazil , Minas Gerais , Montes Claros, Lapa Grande Cave (709 m. a.s.l., 16°42’24.02”S, 43°56’34.48”W), 02.iv.2015, leg. R. L. Ferreira. GoogleMaps

Paratypes: 1 ♂ ( ISLA 13165) and 2 ♀ ( ISLA 13166, ISLA 13170), same data as the holotype GoogleMaps ; 1 ♀ ( ISLA 13162) and 1 immature B (ISLA 13163), Lapa da Santa Cave , Montes Claros, Minas Gerais, Brazil, 918 m .a.s.l., 16°40’53.60”S, 43°59’32.21”W, 08.vi.2015, leg. R. L. Ferreira GoogleMaps .

Diagnosis. Six finely reticulated blades in lateral organs; 5 setae on deutotritosternum; 7 pairs of setae on propeltidium; 3 pairs of setae on metapeltidium; cheliceral fingers with 9 teeth each; coxae II–IV with 5, 5, 2 thick setae; 6 setae (grt, gla, r, esp and 2 esd) on basitarsus of leg IV; opisthosomal tergites II–VI with two pairs of setae t between one setae s on each side; opisthosomal sternites IV–VI with two pairs of a setae flanked by one s seta on each side; first lobe of male genitalia with 12 pairs of setae (2 st + 8 + 2 fusules on each half), second and third lobes with 5 and 4 pairs of setae, respectively; first lobe of female genitalia with 11 pairs of setae; first and second lobes of female genitalia with three and four large cuticular pores, respectively; apical region of the last flagellar article with six setae.

Description of adults.

Body length without flagellum: 1640–1760 μm.

Prosoma. Frontal organ (42–45 μm) formed by two reticulated branches with rounded tips ( Fig. 2A View FIGURE 2 ). Lateral organ with 6 (7 on left side in female III) blades (32–35 μm) pointed-lanceolate and finely reticulated ( Fig. 2B View FIGURE 2 ). Propeltidium with 7 + 7 short setae ( Fig. 3A View FIGURE 3 ). Setae t 1, t 2 and t 3 of metapeltidium 125–137, 102–125 and 105–120 μm long, respectively ( Fig. 3B View FIGURE 3 ). Labrum with 5 + 5 (6 + 5 in female II) short setae. Deuto-tritosternum with 5 setae in U-shaped arrangement ( Fig. 2C View FIGURE 2 ). Basal segment of chelicera (dorsal length: 252–285 μm), with 6 proximal setae (p 4 and p 6 thickened and densely barbed in their distal half) ( Fig. 2D View FIGURE 2 ), 3 distal setae: d 3 (155–161 μm long) longer than d 1 (55–67 μm long) and d 2 (67–76 μm long); d 3 smooth near base and with tiny projections in its distal half; d 1 and d 2 robust, truncated and with tiny projections, mainly in the apex ( Fig. 2E View FIGURE 2 ); and 1 apical seta. Hand of chelicera with 7 setae: 4 dorsal setae, 2 setae in its outer portion (1 close to articulation of movable finger and 1 on a tubercle close to the teeth of the fixed finger) and 1 seta inserted in its inner portion. Fingers with 9 teeth each.

Coxal chaetotaxy. Pedipalp coxa with 19 setae ( Fig. 3C View FIGURE 3 ); coxa I with 15 setae (including two tiny microsetae) ( Fig. 3D View FIGURE 3 ); coxa II with 5 thick (two of the them are shorter in the left coxa of female I, indicated by arrows in figure 2F) and 10 ordinary setae (including two macrosetae) ( Fig. 3E View FIGURE 3 ); coxa III with 5 thick (one of the them is shorter on both sides of female I; one is replaced by a reduced seta with unusual shape on right side of male II, as shown in figure 3G) and 10 ordinary setae (including one macroseta and one adjacent microseta) ( Fig. 3F View FIGURE 3 ) and coxa IV with 2 thick and 8 ordinary setae ( Fig. 3H View FIGURE 3 ).

Palp. tc with 9 setae, two of which are considerably smaller than the others; fe with 8 setae ( Fig. 4A View FIGURE 4 ); ti with 9 setae; bta1 with 2 m and 1 normal seta; bta2 with 3 normal setae and 3 m ( Fig. 4B View FIGURE 4 ); ta1 with 2 m; ta2 with 6 m; ta3 with 1 fs (branches with similar lengths), 1 cs with a basal spine, 2 r, 12 m (one with basal denticle extended to a conspicuous spine) and 8 normal setae ( Fig. 4C View FIGURE 4 ).

Leg I. tc with 13 normal setae, two of which are considerably smaller than the others; fe with 9 normal setae ( Fig. 5A View FIGURE 5 ); pa with 9 normal setae and 1 tb; ti with 9 normal setae ( Fig. 5B View FIGURE 5 ); bta1 with 1 normal seta, 1 m, 2 tb and 1 fs (with the inner branch shorter than the outer branch); bta2 with 3 m, 1 normal seta, 2 tb and 1 long fs; bta3 with 1 r, 1 grt and 1 microseta; bta4 with 5 m, 1 tb and 1 long fs ( Fig. 5C View FIGURE 5 ); ta1 with 5 normal setae; ta2 with 5 m, 1 tb and 1 long fs; ta3 with 5 fs (branches with similar lengths) arranged as fs 1 / fs 2 / fs 3 / fs 4+5 (fs 1 / fs 2+3 / fs 4+ 5 in the left leg of female III and in both legs of male II), rs (rs / fs 1 = 1.9–2.6), 2 r, 1 cs, 13 m and 5 normal setae ( Fig. 5D View FIGURE 5 ).

setae, female III; D, proximal setae (p 1 –p 6) on basal segment of chelicera, male II; E, distal setae (d 1 –d 3) on basal segment of chelicera, female III; F, thick setae on left coxa II, female I, arrows indicate shorter setae. Scale bars: 20 μm (Figs. A – C), 25 μm

(Fig. D) and 50 μm (Figs. E – F).

IVbta. 8–8.6 times longer than wide and with 6 setae (grt, gla, r, esp and 2 esd). Seta r 2.2–2.4 times shorter than the tergal edge of segment and inserted in its distal half (dr / IVbta = 0.5–0.6); two esd also inserted in distal half, distally to r (except in female I, in which the most basal esd level r); esp, gla and grt inserted in proximal half: grt and gla are inserted in the same level, both distal to esp (gla inserted in the same level of esp in right IVbta of male II) ( Fig. 7A View FIGURE 7 ).

Opisthosoma. Tergites II–VI with 3 + 3 dorsal setae, two pairs of t setae (t 1, t 2) between a pair of slender setae (s) ( Fig. 6A View FIGURE 6 ). Sternite III with 2 + 2 setae. Sternites IV–VI each with 2 + 2 thickened setae (a 1, a 2) between a pair of slender setae (s) (inserted caudal to the a setae); a pair of pores present between a 1 setae on sternites IV–VI. Setae a in the opisthosomal segments of males (a 1 62–77 μm; a 2 65–77 μm) shorter than in females (a 1 80–95 μm; a 2 87–100 μm). In females, these setae become gradually thinner from the base towards the apex; in males, they have basal and apical parts with similar width ( Figs 6 View FIGURE 6 B–C, 7B). Segments VII–XI with 8 setae each. The 2 dorsal and 2 ventral setae on the intermediate ring of the flagellum with similar length.

Female genitalia. First lobe with 11 + 11 setae in 5 transverse rows: 2+2 sternal setae (st 1, st 2) (2+ 3 in female III) followed by 2 + 2, 2 + 2, 1 + 1 and 4 + 4 distal setae (a 1 = 25 μm, a 2 = 27–29 μm, a 3 = 35 μm; a 4 longer than a 3); inner surface of the first lobe with a group of 3 large orifices (largest diameter 7–10 μm) on each side (two orifices in the left side in female I) and a medial pair of smaller orifices (2 μm) ( Figs 6D View FIGURE 6 , 7D View FIGURE 7 ). Second lobe with 3 + 3 setae (x = 32–39 μm, y = 35–37 μm, z = 25–28 μm); presence of cuticular spines and a group of 4 large orifices (largest diameter 10–12 μm) on each half ( Figs 6D View FIGURE 6 , 7E View FIGURE 7 ).

Male genitalia. 12 + 12 setae: 2 + 2 anterior (st 1, st 2) setae close to first lobe and 10 + 10 setae in the first lobe (including 2 + 2 fusules). Fusules close to each other, with a dilated conical base, a setiform end and internal canals. Each half of second lobe subtriangular, with a simple and thin apex and 5 setae. Each half of third lobe also subtriangular and with a simple tip, presenting 4 setae (w, x, y and z; z inserted in a conical tubercle) and eight small orifices ( Fig. 7F View FIGURE 7 ).

Flagellum. Present only in the holotype, missing in the other adult specimens. Longer than the body (2089 μm) and formed by 13 articles. Articles I, II, III, V, VII and IX with an apical crown of spikes. The setae on articles I–X are inserted in the distal half, on article XI nearly in the middle, and on article XII in the proximal half. Last article with 8 setae inserted in the proximal half and six terminal setae ( Fig. 8 View FIGURE 8 ). The number of setae and the length of each flagellar article are shown in Table 1.