Neocaeculus setecidades, Ott & Ott, 2018

Ott, Ana Paula & Ott, Ricardo, 2018, A new species of rake-legged mite Neocaeculus (Acari, Caeculidae) from Brazilian semiarid and new data on distribution of Andocaeculus caioi, Iheringia, Série Zoologia (e 2018027) 108, pp. 1-10 : 2-4

Neocaeculus setecidades sp. nov.

( Figs 1-38 )

urn:lsid:zoobank.org:act:DB68BBD3-4035-4713-863B-9D7F6F51574E

Type material. Holotype ♂ from Parque Nacional Sete Cidades (04°06’44.2”S - 41°41’47.7”W), sample site PNC7C 0323, Piracuruca, Piauí, Brazil, 06.XII.2006, L. C. Carvalho et al. leg. ( MPEG - ACA 0081 ) . Paratypes: ♀ same data of holotype ; ♀, Parque Nacional Sete Cidades [04°05’59”S, 41°42’33”W], Brasileira e Piracuruca, Piauí, Brazil, 2006-2007, same collector as holotype ( MPEG ACA 0084 ) ; ♂ and 1 juv. ( MCN ACA 1929 ; ex. MPEG ACA 0084 ) same data above ; ♀, sample site PNC7C 0951, Piracuruca (04°05’57.5”S - 41°43’00.7”W), 26.I.2007, same collector above ( MPEG ACA 0080 ) ; 1 juv. same locality, date and collector above ( MPEG ACA 0082 ) .

Etymology. The noun in apposition is taken from the type locality.

Diagnosis. Neocaeculus setecidades sp. nov. is close to N. bornemisszai Coineau & Enns, 1969 , N. johnstoni Coineau, 1974 , N. kinnearae Taylor, 2014 , N. knoepffleri Coineau & Enns, 1969 and N. womersleyi Coineau, 1974 in having a narrow and straight nasus bothridial setae bo ( Fig. 11 ) rather to “globose-capitate” ones (see COINEAU, 1967: 59, fig. 2A). The species can be distiguished from N. bruchi by the different spines number and distribution on leg I (see BERLESE, 1916: 290, 291). It can be recognized by the presence of 5-6 blunt tip spines on prolateral side of trochanter I ( Figs 1, 2, 4 , 15 ).

Description. Male (MPEG ACA 0081, holotype). Idiossoma 1,481 long, 950 wide.

Dorsum: yellowish brown tegument with dark brown markings surrounding sclerites (in ethanol, as in Figs 1-3 ). Aspidosomal sclerite yellowish brown with brown markings, mesal portion lighter, anterior portion much lighter, almost whitish, 531 long, 580 wide; setae Pa close together, on anterior border of sclerite; setae Pm close together on the anterior third of sclerite; setae Pp wide appart, on the posterior third of sclerite, just behind the posterior eyes line ( Figs 6, 8 ). Two pair of eyes on small rounded and brown sclerite at level of posterior third of aspidosomal sclerite ( Figs 1, 4 , 6, 8 ). Centrodorsal sclerite yellowish brown with brown markings, 612 long, 483 wide; setae a1, b1, c1 present; setae a1 and b1 closer together as both c1, a1 separated from each other around one and a half time their length and b1 about two times their length, setae c1 wider apart from each other, around three to four times their length ( Figs 6, 8 ). Lateral sclerite yellowish brown with brown markings, 692 long, 193 wide; setae a2, b2, c2 present, all positioned on middle line of sclerite, a2, b2 single, c2 double but not close together; lyrifissure ia transversal, between a2 and b2, on the ectal border of sclerite; lyrifissure im obliquous between b2 and c2, somewhat apart from the ectal border of the sclerite ( Figs 6, 8 ). Medial sclerite in one piece, occupying the whole width of posterior portion of idiossoma, yellowish brown with brown markings, narrow trapezoidal shaped, 225 long, 757 wide; setae d1, d2 present, single, ds present; all setae almost in transversal straight line with d2 at lateral border of sclerite. Posterior sclerites very weakly defined, 64 long, 242 wide; setae e1, e2 present, es absent ( Figs 6, 8 ). Pseudoanal sclerite not clearly defined, setae h1, h2 and hs present.

Venter: yellowish brown tegument with brown ridges; epimeres brown, wrinkled aspect; dark brown genital valve, brown anal valves ( Figs 2 , 7 ). Epimeres I not touching the gnathosoma, with a clear seam between them; epimeres I and II totally fused from the base to half of its length showing a groove from this point until distal end; epimeres I with four equaly spaced medial clavate setae, which increases in size from the proximal to the distal position; epimeres II with two medial clavate setae, close together and positioned at half length of the epimere; epimeres II and III, separated by a seam; epimeres III and IV fused, with a groove between them on its total length; both with two small medial, almost same sized clavate setae.

Genital valves with five pairs of small and thin needle like setae, each valve 290 long, 32 wide, genital; agenital sclerite well sclerotized, brown, triangular in shape, 225 long, 161, wide. Anal valves with two-three clavate setae, 209 long, 64 wide; pseudoanal sclerites, brown, semicircular, with two-three clavate setae, 242 long, 80 wide, reaching until three quarters of the total length of the anal valves ( Figs 7, 9 ). Remaining ventral a genital seta distribution as in Fig. 9 . Internal genital sclerite bell shaped, with 4 pairs of visible setae forming a circular pattern on the anterior portion, no visible acetabula ( Figs. 7 , 14 ).

Gnathosoma: nasu seta Po very short, bothridia bo long and narrow ( Fig. 11 ); subcapitulum dark brown, wrinkled aspect, with two pairs of clavate setae. Hypostome with one pair of clavate setae near base. Chelicera with one dorso-distal needle like seta; movable finger terminal, fixed finger regressed and tooth like. Palp ( Figs 12, 13 ) four segmented, with femur-genu not fused, femur with two dorsal clavate setae and genu with a single clavate seta; tibia with five setae being two dorso-retrolateral clavate and three robust prolateral spiniform setae, being the proximal one sharp pointed and both distal with blunt tip; tibia also with one dorsal solenidion ( Fig. 12 ); tarsus with three setae, one ventral, one prolateral and one retrolaterally directed, five eupathidia: four more prolateral positioned being the two median very close together, the fifth one slightly in retrolateral position ( Fig. 13 ).

Legs ( Figs 10 , 15-38 ): light brown with whitish clavate setae on dorsum, laterals and some scarce ones ventrally at trochanter, basifemur, femur and genu of legs II-IV; all legs with divided femura; rake setae light orange. Distal tip of tarsi of legs I-IV bearing large and peculiar foliar setae positioned one on each side of the tarsal claws ( Figs 24, 25 , 36 ). Legs I and II bearing very long rake like setae (mainly on anterior and ventral sides of femur, genu and tibia), most setae and eupathidia originating on tubercles. Leg I ( Figs 15, 16 , 23-30 ) with 16 visible eupathidia ( Figs 26, 27 ), distributed on basifemur (2), femur (1) genu (2), tibia (4) and tarsus (7); trochanter with five to six strong, long, narrow and slightly clavate prolateral setae; one distal solenidion on retrolateral side of tibia ( Fig. 28 ) and a very large prolateral tarsal solenidium (11.90 diameter; Figs 10 , 16 , 29, 30 ) present at distal third of tarsus; tarsal bothridium absent ( Figs 16 , 23 ); clavate setae distribution: tr, a1-1-1- 1-1 (very long, sometimes six setae), d3-3-3, p1-1-0; bf, a0-1-0, d3-3-2; fe, d0-2-2; ge, d3-3-2-3-1, p1-1-1-0, vp1-0- 1-1; ti, d3-1-3-1-1, vp1-0-0-0; ta, d1-0-0, p1-0-0, vp, 1-1-1; needle like setae distribution: bf, va1; fe, a1; ge, a1-1, vp1; ti, a1-1-1-1, vp1-1-1; ta, a1-1-1-1, d0-1-0, vp1-1-1-1. Leg II ( Figs 17, 18 , 31, 32 ) with 18 visible eupathidia, distributed on basifemur (2), femur (2), genu (4), tibia (5) and tarsus (8) ( Figs 17, 18 ); one distal solenidion on tibia in retrolateral position ( Fig. 32 ) and one very large prolateral solenidium (11.00 diameter; Fig. 18 ) present at distal third of tarsus; tarsal bothridium absent ( Figs 18 , 31 ); clavate setae distribution: tr, a1-0-0, d1-3-1; bf, a1-0, d1-3-2; fe, a1, d2-1; ge, a1-1 d3-3-1, vp1-1-0-0; ti, d2-2-3, va1-1-1-1; ta, d2-1-1; needle like setae distribution: bf, vp1; ge, va1-1, vp1-0; ti, v0-1; ta, a1-1-1-1, vp1-1-1-1. Leg III ( Figs 19, 20 , 33-36 ) with 14 visible eupathidia distributed on basifemur (2), femur (1) genu (2) tibia (5) and tarsus (4) ( Figs 19, 20 ), one distal solenidion on tibia ( Fig. 35 ) in retrolateral position; one dorsal bothridium (159.50 long) at three quarters of the length of tarsus ( Figs 20 , 33, 34 ); clavate setae distribution: tr, a2-1-1, d1-2-2; bf, a1, d1-2; fe, a1, d1; ge, d2-3-2, v0-1, vp1-1; ti, d2-1-1,va2-0-0-0; ta, d2-2-0; needle like setae distribution: ti, va0-1-1-1, v1-1-1-1; ta, v1-1-1,va1-1-1-1. Leg IV (figs 21, 22, 37, 38) with 15 visible eupathidia distributed on femur (2), genu (3), tibia (7) and tarsus (3) ( Figs 21, 22 ), one dorsal long bothridium (173.80 long) positioned near to three quarters of the length of tarsus ( Figs 22 , 37, 38 ); clavate setae distribution: tr, a1-0-1,d1-1-1; bf, d2-1, a1, v2-0-1; fe, d1; ge, a0-0-1, d2-1-1, va1-1-1; ti, d2-0-1-0; ta, d2-2-0; needle like setae distribution: ti, va1-1-1-1-1, vp1- 1-1-1-0; ta, va1-1-1-1-1, vp0-1-1-1-1.

Variation (n=2). Idiossoma length 1,481 (no variation detecded), width 950-966.

Female (MPEG ACA 0084, paratype, Figs 1-5 ). Idiossoma length 1,666; width 1,137. As for male except noted.Aspidosomal sclerite, 580 long, 628 wide. Centrodorsal sclerite 757 long, 547 wide. Lateral sclerite 869 long, 225 wide. Medial sclerite 193 long, 338 wide. Posterior sclerites 209 long, 403 wide.

Genital valves, 290 long, 32 wide; aggenital sclerite, proportionally smaller as in male, 225 long, 113 wide, reaching just to the half length of the genital valves. Adanal sclerites 306 long, 80 wide; pseudoanal sclerites 338 long, 97 wide ( Fig. 2 ).

Variation (n=3). Idiossoma length 1,433 -1,666, width 950-1,137.

Other examined material. None.

Distribution. Known only for the type locality.

Natural History. The available information for sample sites of some of the collected specimens indicate that the species can be found in grasslands (pitfall sampling method; PN7C 0323 sample site; Figs 39, 40 ) and dry semideciduous forests litter (winkler sampling method; PNC7C 0951 sample site; Figs 41, 42 ), both sites are defined respectively as “campo graminoide cespitoso médio” and “floresta tropical semidecídua” ( OLIVEIRA et al., 2007). The “Parque Nacional Sete Cidades” is mainly geomorphologically characterized by sand stone formations as table mountais (“chapadas”), sand stone slopes (“cuestas”) and typic sedimentary basins sandy soil ( SANTOS & PELLERIN, 2003). The collection sites characteristics and methodologies evidences suggests that the species is probably a sandy ground/litter dweller (also observed by the collector, L. Carvalho pers. comm.) differently from the another species registered to Brazil, A. caioi , which was until now found exclusively in outcrops under stones ( OTT & OTT, 2014).

Figures

Figs 1-5. Neocaeculus setecidades sp. nov., paratype ♀: 1, dorsal view; 2, ventral view; 3, lateral view; 4, anterior portion of aspidosomal sclerite, dorsal view; 5, tarsi of legs I, dorso-anterior view. Scales bars: 1, 2, 3, 1000 μm; 4, 250 μm; 5, 100 μm

Figs 6-9. Neocaeculus setecidades sp. nov., holotype ♂, cleared: 6, 8, dorsal view; 7, 9, ventral view. Scale bars: 500 μm.

Figs 10-14. Neocaeculus setecidades sp. nov., holotype ♂: 10, anterior portion of tarsus of leg I, prolateral view; 11, anterior portion of aspidosomal sclerite, dorsal view; 12, palp, dorsal view; 13, palp, ventral view; 14, internal genital sclerite, ventral view (bo, bothridium; eu, eupathidium; fs, foliar seta; Po, naso seta; sol, solenidion; ts, tarsal solenidion). Scale bars: 10, 12, 13, 50 μm; 11, 250 μm; 14, 100 μm.

Figs 15-22. Neocaeculus setecidades sp. nov.: 15, 17, 19, 21, trochanter, basifemur, femur and genu, respectively Legs I, II, III, IV, dorso-prolateral view; 16, 18, 20, 22, tibia and tarsus, respectively Legs I, II, III, IV, prolateral view (bt, tarsal bothridium; sol, solenidion; ts, tarsal solenidion). Scale bar: 250 μm. Dotted circles indicate solenidia and eupathidia at retrolateral positions.

Figs 23-30. Neocaeculus setecidades sp. nov., paratype ♂, scanning electron microscope images, Leg I: 23, tarsus, dorso-retrolateral view; 24, tarsal claws, dorsal view (arrows: foliar setae); 25, same, retrolateral view (arrow: foliar seta); 26, tarsal distal eupathidium, ventral view; 27, tarsal medial eupathidium elevated base, lateral view (arrow: eupathidium); 28, tibial solenidion, retrolateral view; 29, tarsus, prolateral view (arrow: tarsal solenidion); 30, same, solenidion detail. Scale bars: 23, 100 μm; 24, 25, 27, 28, 30, 10 μm; 26, 5 μm; 29, 50 μm.

Figs 31-38. Neocaeculus setecidades sp. nov., paratype ♂, scanning electron microscope images: 31, 32, Leg II; 33-36, Leg III; 37, 38, Leg IV. Fig. 31, tarsus, dorso-prolateral view; 32, tibial solenidion, dorso-retrolateral view; 33, tarsus, retrolateral view (arrow: tarsal bothridium); 34, tarsal bothridium, dorso-retrolateral view; 35, tibial solenidion, retrolateral view; 36, tarsal claws, retrolatertal view (arrow: foliar seta); 37, tarsus, retrolateral view (arrow: tarsal bothridium); 38, tarsal bothridium base, dorso-retrolateral view. Scale bars: 31, 50 μm; 32, 34, 36, 38, 10 μm; 33, 37, 100 μm; 35, 5 μm.

Figs 39-42. Neocaeculus setecidades sp. nov. habitats in the Parque Nacional Sete Cidades, Piracuruca, Piauí, Brazil. 39, 40, grasslands; 41, 42, dry semideciduous Forest.