Synkrotima tsalakpmenoi, Fernandez & Theron & Leiva & Jordaan, 2018

Fernandez, Nestor, Theron, Pieter, Leiva, Sergio & Jordaan, Anine, 2018, Revision of the family Carabodidae (Acari: Oribatida) XVI. Synkrotima tsalakpmenoi sp. nov. from Zimbabwe and Kenya, and Congocepheus thailandae sp. nov. from Thailand, including a complementary study of Cavaecarabodes hauseri (Mahunka 1989), Zootaxa 4504 (3), pp. 371-389 : 372-379

Synkrotima tsalakpmenoi sp. nov.

( Figures 1–41 )

Etymology. The specific epithet “tsalakpmenoi” is derived from (tσαλακωµένo Greek=, wrinkled = English) due to characteristics of the notogastral cuticular surface.

Material examined. Holotype. Female “ Zimbabwe, Mutare II/1945. Leg. R. Mussard ”; material deposited in the Collection of the Natural History Museum of Geneva (MHNG), Switzerland; preserved in 46% ethanol.

Paratypes. Two adult females from different localities, namely “ Zimbabwe, Mutare II/1945. Leg. R. Mussard ” and “ Kenya. Embu distr. Kirimiri Forest, Ouest de Runyenje, alt. 1586 m; tamisage dans la forêt 13 /X/1977. Leg. V. Mahnert & J.L. Perret ”; material deposited in the Collection of the MHNG; preserved in 46% ethanol. Material studied by means of SEM: three female specimens, not deposited .

Diagnosis (adult female). Integument. Notogaster: longitudinally aligned cuticular chords forming rugose integument.

Setation. Lanceolate, thick, medial longitudinal zone elevated, with small dentitions, triangular in crosssection: notogastral; adanal setae. Lanceolate, with small dentitions, barbate: le. Lanceolate, more or less flat, with elevated medial longitudinal zone: rostral, lamellar setae.

Simple, smooth: anal; simple, with small barbs; epimeral setae 4a, 4b particular shape: 4a thin, elongate, 4b triangular, curved. Simple, sharply tipped: subcapitular setae; flabellate: genital, aggenital setae.

Prodorsum. Complex elevated interlamellar process flat, slightly elevated; polyhedral lateral processes with parallel oblique grooves, one on either side; T-shaped anterior projection. Lamellae resembling elevated ribbon.

Notogaster. Humeral apophysis ovoid, anterior end barely overlapping posterior bothridial zone.

Lateral zone. Deep supratutorial depression; small anterior supratutorial depression. Depressions above and behind acetabulum IV; longitudinal oblique depression posterior to acetabulum IV.

Ventral region. Discidium with triangular sharp tip. Genital plate smaller than anal plate. Shallow depression surrounding elevated zone bearing genital plate; anterior genital furrow present; genital neotrichy 6 to 11 pairs of setae, symmetric or asymmetric distribution.

Large, deep furrow surrounding anterior and medial zones of anal opening, not extending to posterior zone. Adanal setae ad 3 and ad 2 situated on lateral furrow surrounding anal opening; ad 1, outside the lateral furrow.

Description. Measurements. Female, length 827 (658–958) (ten animals measured), width 347 (298–438) (ten animals measured).

Shape. Prodorsum polyhedral, notogaster elongate ovoid ( Figures 1, 2 , 10 )

Colour. Specimens without cerotegument: brown to dark brown, slightly shiny when observed in reflected light.

Cerotegument. Present: thin granular layer, following cuticular microsculpture; thickness 0.5 to 0.9 ( Figures 12, 15 , 24 ).

Integument. Pusticulate: notogaster ( Figure 8 ); bothridial zone ( Figures 14, 19 ); pedotectum II ( Figure 22 ). Rugose, formed by cuticular cords, principally aligned longitudinally ( Figures 1, 2, 8 , 12, 13, 20 indicated by ¡): notogaster ( Figures 1, 8 , 12, 13, 20 ), in some specimens elevations on central notogastral zone more accentuated ( Figures 1, 8 , 12, 20 ), in others less ( Figures 2 , 13 ); prodorsal zone of elevated interlamellar process (e.i.p) ( Figure 4 ); Smooth: prodorsum (1, 2, 12, 13, 16, 21, 38, 40); humeral apophysis (h.ap) ( Figure 17 ); ventral region (epimeral zone, ano-adanal zone) ( Figure 35 ); anal plate ( Figure 36 ); genital plate ( Figure 37 ); subcapitulum ( Figure 39 ).

Setation. Lanceolate, thick elevated medial longitudinal zone, with small dentitions, triangular in cross-section ( Figures 3, 7 ): interlamellar (in) ( Figures 4 , 10 ); notogastral c 1, c 2, da, dm, dp, la, lm, lp, p 1, p 2, p 3, h 1, h 2, h 3 ( Figures 5, 6 , 26 ); adanal ( Figures 29, 31 ). Lanceolate, more or less flat, with elevated medial longitudinal zone: ro, le ( Figures 4 , 16 , 25 ); simple: anal ( Figure 27 ). Epimeral setae simple, with small barbs ( Figure 18 ), but setae 4a, 4b particular in shape; 4a is simple, elongate, thin, small barbs ( Figure 33 ); 4b simple, triangular, curving, small barbs ( Figure 32 ); simple, sharply tipped: subcapitular setae; flabellate: genital; aggenital setae ( Figures 30, 34 ).

Prodorsum. Polyhedral (in dorsal view) ( Figures 1, 2 , 10 ); triangular to polyhedral in frontal view ( Figure 38 ). Complex elevated interlamellar process (e.i.p): flat or slightly elevated ( Figures 1, 2 , 12, 13 ) forming two separate lateral processes, polyhedral in shape ( Figures 38, 40 ). In lateral view each lateral process terminating in sharp tip, situated above le setal insertion ( Figure 4 indicated by white asterisk in black square).

Two oblique parallel grooves on elevated zone of lateral process ( Figures 1, 2, 4 , 10 , 12, 13 , 38, 40 indicated by5); finger-shaped projection on anterior e.i.p, delineating a T-shaped, forward extending structure ( Figures 2 , 38 , indicated by ¿); in setae curved ( Figure 1, 2, 4 ), directing externally, inserted in front of e.i.p below lateral process ( Figures 4 , 12 ).

Bothidial zone with pusticulate cuticula ( Figure 19 ). Bothridium (bo) cup-shaped with large, smooth, incomplete bothridial ring (bo.ri) ( Figure 14 ); bothridial opening lateral, directing downward ( Figures 12, 13 ); bothridial tooth (bo.to) clearly visible, rounded ( Figure 14 ).

Sensillus (Si) filiform, barbate, arching to the top, tip usually pointed ( Figures 1, 2 , 12, 14 ); lamellar setae (le) inserted laterally on anterior part of lamellae ( Figures 15, 16 ) between lamellar tip and le setal insertion zone; conspicuous lamellar tip (la.ti) ( Figure 16 ); curved rostral setae (ro) ( Figures 12, 13 , 21, 25 ), directing downwards; le setal insertion behind ro insertion setal level ( Figures 15, 16 ); large deep dorsosejugal suture (d.sj) ( Figures 1, 2 , 12, 13 ).

Notogaster. Shape: anterior and posterior zone oval (in dorsal view) ( Figures 1, 2 , 10 ); convex in lateral view ( Figures 9 , 12, 13 ); circumgastric furrow (s.c) present, easily discernible, situated antiaxially to c 1, c 2, la, lm, lp, h 2 and paraxially to h 3, p 3, p 2, p 1 setal insertion level ( Figures 1, 2 , 10,13 indicated byl) (See Remarks). Fourteen pairs of setae (c 1, c 2, da, dm, dp, la, lm, lp, h 1, h 2, h 3, p 1, p 2, p 3), all similar: lanceolate, thick, with elevated medial longitudinal zone, small dentitions, triangular in cross-section. However, c 2 setae differ slightly in shape and crosssection ( Figures 6, 7 ) from other notogastral setae ( Figures 3, 5 , da setae used as example); all setae (except c 2) extending backward; c 2 setae directing obliquely inwards ( Figures 1, 2 , 10 , 12 ).

Humeral apophysis (h.ap) ovoid; anterior end barely overlapping posterior bothridial zone ( Figures 9 , 12, 13 ); h.ap with some transversal cuticular depressions ( Figure 17 indicated by¿), resulting in an undulate aspect to h.ap. Lyrifissures hardly discernible, only rounded im is observed ( Figure 20 ).

Lateral region. Prodorsum: in setae clearly visible, situated in front of flat e.i.p ( Figures 4 , 12, 13 ); l.l.f well visible ( Figure 16 ). Lamellae resembling elevated ribbon; Tutorium (Tu) strongly curving cuticular thickening ( Figure 13 ); supratutorial depression (s.tu.d) deep ( Figure 9 , 13, 15 ); small anterior supratutorial depression (a.tu.d) ( Figures 9 , 21 ). Large deep posterior tutorial depression (p.tu.d) situated posteriorly on Tu basal zone ( Figure 9 , 13 , 21 ). Pedotectum I (Pd I) prominent extending lamina, anteriorly rounded; large ovoid depression (dep) on posterior zone near Pedotectum II (Pd II); small, ovoid lamina directing downward ( Figures 9 , 13 , 22 ). Discidium (dis) hardly discernible (See Ventral region).

Several depressions (dep) clearly visible basally to Pd I and above and behind acetabulum IV ( Figure 9 , 13 , 21 , 41 ). Anal plate terminating in long sharp tip ( Figure 23 ), more clearly visible in lateral than ventral view.

Ventral region. Epimeres well delimited; 1 and 2 defined by deep furrows; bo.1, bo.2, bo.sj, 3 and 4 not noticeably separated; apo.1, apo.2, apo.sj and apo.3 clearly visible ( Figures 11 , 35 ).

Epimeral chaetotaxy 3-1-3-3; setae 1a, 2a, 3a short. Epimeral setae 4b ( Figure 10 , 32 , 35 ), and 4a ( Figure 33 ) differ in shape. Epimeral zone with medially deep polyhedral depression ( Figures 11 , 35 indicated by s). Discidium (dis) easily observed ( Figure 35 ), triangular sharp tip. Genital plate slightly smaller than anal plate ( Figure 35 ). Genital plate situated on elevated zone, externally surrounded by shallow depression (dep) ( Figure 35 ). This furrow is connected to the anterior genital furrow (a.g.f) ( Figures 11 , 35 , trajectory indicated by l).

Genital plate with neotrichy: 6 to 11 pairs of setae ( Figures 11 , 35, 37 ) with symmetric or asymmetric distribution (See Remarks). Setae generally flabellate ( Figure 34 ), some with very irregular shapes ( Figure 37 ); in other cases setae absent, only insertions present (large insertions) ( Figure 37 ).

Aggenital (ag) setae far from posterior border of genital opening, but situated posterolaterally on the surrounding genital furrow ( Figures 11 , 35 ).

Anal plate terminating in long sharp tip ( Figure 23 , and 36 indicated byY). Large deep furrow observed surrounding anal plate anteriorly and medially, not completely surrounding the rear; in one instance the anal plate was deformed on one side.

Three pairs of adanal setae: ad 3 and ad 2 situated in lateral furrow of anal plate; ad 1 situated posteriorly on anal plate, outside lateral furrow ( Figures 10 , 35 ); rounded to polyhedral dep ( Figures 11 , 35 ) situated externally to genital and anal openings.

Legs. Setal formulae I (1-4-3-4-17 -1) (1-2-2); II (1-3-3-3-15 -1) (1-1-2); III (2-2-1-2-14 -1) (1-1-0); IV (1-2-2- 2-12) (0-1-0).

Remarks. Large variations in size were observed in both populations ( Zimbabwe and Kenya). Initially the authors associated this variation in size with differences between males and females, but no correlation between sex and size was observed; in both sexes there were small and large specimens; sexes could be distinguished only by dissection.

Setae h 1 were not included when indicating the trajectory of s.c, as their position is variable ( Figures 1, 2 ), in some cases aligned to h 2 setae ( Figure 1 ) and in others near p 2 setae ( Figure 2 ). Positions of setae p 1, p 2, p 3 also varied.

Small dentitions present on surfaces of notogastral setae differ in size and number. In lateral view differences between notogastral cuticular ornamentations are easily visible; these variations are common in populations from Zimbabwe ( Figure 12 ) and Kenya ( Figure 13 ), but more so in populations from Kenya.

Large variation in the number of setae due to genital neotrichy, with asymmetry being very common. Setae frequently number 6–8 on each side; in one specimen from Zimbabwe only 4 setae were observed on a side, while in specimens from Kenya, six are most common. The largest variation was found in specimens from Kenya, with eleven setae on a side of the genital plate.

Depressions are very numerous on the ventral plate, clearly visible in ventral view; in lateral view a longitudinal oblique depression can be seen ( Figure 41 indicated by 5), usually concealed by femur IV.

Figures

FIGURES 1–8. Synkrotima tsalakpmenoi sp. nov. Adult female, SEM. 1. dorsal view, female (Zimbabwe); 2. dorsal view, female (Kenya); 3. frontal view, broken notogastral da seta; 4. elevated interlamellar protuberance and interlamellar seta; 5. notogastral da seta; 6. notogastral c 2 seta; 7. frontal view, broken notogastral c 2 seta; 8. notogastral seta da, and notogastral elevated cuticular ridges. Abbreviations: see Material and Methods. Scale bars: 1=590 µm; 2=590 µm; 3=5 µm; 4=100 µm; 5=10 µm; 6=59 µm; 7=5µm; 8=40 µm.

FIGURES 9–11. Synkrotima tsalakpmenoi sp. nov. Adult female, optical microscopy. 9. lateral view; 10. dorsal view; 11. ventral view. Scale bars: 9=200 µm; 10=250 µm; 11=320 µm.

FIGURES 12–20. Synkrotima tsalakpmenoi sp. nov. Adult female, SEM. 12. partial lateral view (Zimbabwe); 13. lateral view (Kenya); 14. bothridium and sensillus; 15. lamellar setae; 16. prodorsal anterolateral zone; 17. humeral apophysis, lateral view; 18. epimeral seta 3a; 19. bothridial cuticular microsculpture; 20. dorsoposterior view. Scale bars: 12; 13=590 µm; 14=20 µm; 15=50 µm; 16=100 µm; 17=100 µm; 18=20 µm; 19=15 µm; 20=590 µm.

FIGURES 21–34. Synkrotima tsalakpmenoi sp. nov. Adult female, SEM. 21. anterolateral view; 22. pedotectum II, lateral view; 23. anal plate, sharp tip; 24. cerotegumental layer, bothridial zone; 25. rostral seta; 26. notogastral seta p 3; 27. anal seta, an 2; 28. subcapitular seta h; 29. adanal seta, ad 2, dorsal view; 30. aggenital seta; 31. adanal seta ad 3, lateral view; 32. epimeral seta, 4b; 33. epimeral seta 4a; 34. genital seta. Scale bars: 21=100 µm; 22=59 µm; 23=10 µm; 24=30 µm; 25=10 µm; 26=15 µm; 27=5µm; 28=10 µm; 29=10 µm; 30=20 µm; 31=10 µm; 32=20 µm; 33=20 µm; 34=25 µm.

FIGURES 35–41. Synkrotima tsalakpmenoi sp. nov. Adult female, SEM. 35. ventrolateral view; 36. anal plates; 37. genital plates; 38. prodorsum frontal view; 39. subcapitulum, lateral view; 40. elevated interlamellar process, dorsal view; 41. posterolateral view. Scale bars: 35=590 µm; 36=100 µm; 37=59 µm; 38=200 µm; 39=100 µm; 40=100 µm; 41=180 µm.