Congocepheus thailandae, 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 : 379-385

Congocepheus thailandae sp. nov.

( Figures 42–67 )

Etymology. The specific epithet “thailandae” derives from Thailand, country of origin of type material.

Material examined. Holotype . Female. “ THAILAND N°286. NE Bangkok Khao Yai Nai Park.759–859 mt. 26/XI /– 3/XII/85. Leg. LOBL”; material deposited in the Collection of the Natural History Museum of Geneva (NHMG), Switzerland; preserved in 70% ethanol. Paratype. One adult female, same locality and date as Holotype; deposited in Collection of MHNG; preserved in 46 % ethanol. Material studied with SEM: three specimens, not deposited .

Diagnosis. Prodorsum. Large, triangular, central zone depressed or flat; setae in large, curved, situated on elevated interlamellar process, directing externally; ro setae curved, directing anteriorly; lamelar setae inserted far from apical lamellar zone. Anterior zone of lamellae welded to lateral prodorsal zone, lacking lamellar tip. Sensillus uncinate. Bothridial ring smooth; low lamellar furrow present, only slightly developed. Cornea superior of naso, with semicircular groove in posterior zone.

Notogaster. Fingerlike projection large, extending forward. Fourteen pairs of setae: c 1, c 2, da, dm, dp, la, lm, lp, h 1, h 2, situated on promontories; h 3, p 1, p 2, p 3, situated marginally on notogaster, all setae directing backwards; setae c 1, c 2 parallel and located side by side; integument with rugous elevated ridges.

Ventral region. Epimeral, central zones depressed, marginal region elevated. Epimera 3–4 fused; epimeral chaetotaxy 1-1-3-3; four pairs of genital setae in a simple line; ag setae situated on rounded elevated structure.

Description. Measurements: SEM 556 (460–602) x 260 (242–273) (measurements on three specimens). Light microscopy: 580 (560–582) x 273 (256–281).

Shape: Elongate oval ( Figure 42 ).

Colour: Specimens without cerotegument, light brown to brown, observed in reflected light.

Cerotegument. Thin grainy layer (ce) ( Figure 69 , indicated by 5), mainly on posterior zone of notogaster ( Figure 57 ) and epimeral zone ( Figure 61 ), and around ag setal insertion ( Figure 68 ); rest of body and legs absent; cerotegumental layer may have been affected by the long period in conservation liquid.

Integument. Foveate-foveolate ( Figure 48 , indicated byw): prodorsum: lamellar zone up to l.l.f ( Figures 42, 43 ); anterior of prodorsum around CSO ( Figure 43 ); bothridial and p.p.d zones ( Figures 42, 47 ); notogaster: h.ap ( Figure 42 ); Pd I, Pd II and Tu ( Figures 43 , 52 ).

Circular-ovoid fovea: notogastral zone: n.a.d and both sides of f.l.p ( Figure 42 ).Ventral region: subcapitular zone h setae ( Figure 58 ); epimeral zone (Figures 61,62,63); around genital opening ( Figure 56 ); aggenital zone, but not very close to ag setae ( Figure 68 ); lateral to ventral dep ( Figure 61 ). Legs: femurs I, II and trochanter, femur III, IV ( Figure 52 ).

Rugous with elevated ridges: lateral notogastral margin, zone of setae p 1, p 2, p 3, h 3, up to h.ap level ( Figure 57 indicated by ●), in this zone, combined with circular-ovoid fovea; marginal ventral region; anal zone ( Figure 61 ).

Pusticulate ( Figures 69, 70 indicated by¿): zone epimeral surrounding setae 4c ( Figure 63 ); zone near ag setae ( Figure 68 ).

Setation. Lanceolate elongate with: smooth surface: ag setae ( Figure 68 ); medial ridge: notogastral c 1, c 2, da, dm, dp, la, lm, lp ( Figures 42, 45 ) ad setae ( Figure 67 ); large basal, and thin anterior zone, medial ridge several lines: notogastral setae: h 3, p 3, p 2, p 1 ( Figures 53, 57, 60 ); rugous surface: epimeral setae 1a, 2a, 3a, 3b, 4a, 4b ( Figures 62, 63, 65 ); thin medial furrow: ro setae ( Figure 46 ); two parallel lines with small barbs: in setae ( Figure 44 ); barbate on both sides: le setae ( Figure 54 ).

Filiform, irregular margin: epimeral setae, 3c, 4c ( Figures 64 ). Simple: subcapitular (a, m, h) ( Figures 58, 59 ), ge ( Figure 56 ), an ( Figure 66 ).

Prodorsum. Triangular (dorsal view) ( Figure 42 ); convex in lateral view ( Figure 49 ); rostral margin rounded (Figures 43,51); e.i.p elevated ( Figure 52 ), central depressed zone flat (Figures 42,43 indicated by¿); large curving setae in, situated on e.i.p, directing externally ( Figures 42, 43 ); ro setae clearly visible, curved, directing anteriorly, apical tips far from one another ( Figure 43 ); le setae inserted laterally to lam, far from apical lamellar zone; setal insertion level more or less same level as ro setal insertion ( Figures 43 ); anterior zone of lamellae welded to lateral prodorsal zone, lamellar tip absent ( Figure 54 ).

Sensillus (si) uncinate ( Figure 47 ). Bothridial ring (bo.ri) smooth, well defined, with bothridial tooth; l.l.f present, slightly developed ( Figures 42, 43 , 51 ), CSO present between ro setae ( Figures 43 , 51 ); poorly developed semicircular groove (c.g) in posterior zone ( Figure 43 ).

Notogaster. Shape: in dorsal view anterior polyhedral and posterior oval ( Figure 42 ); in lateral view convex ( Figures 49 , 52 ); d.sj narrow, slightly curving, well delimited; notogastral anterior depression (n.a.d) clearly visible ( Figure 42 ).

Notogaster with promontories ( Figure 49 ); large, forward extending finger-like projection (f.l.p) in front of promontory zone ( Figure 42 ). Lateral to f.l.p, at level of origin of lateral promontories, depressed semi-circular area ( Figure 42 indicated by n). 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. Four longitudinally aligned promontories separated by depressed zone ( Figures 42 , 49 ); setae c 1, c 2, da, dm, dp, situated on aligned central promontories; la, lm, lp, h 1, h 2 situated on aligned lateral promontories ( Figures 42 , 49 , 52 ); h 3, p 1, p 2, p 3, situated marginally notogastral zone ( Figures 42 , 49 , 52, 57 ); all setae directing backwards; setae c 1, c 2 situated side by side, parallel ( Figure 42 ); polyhedral h.ap large, easily observed ( Figures 42 , 49 , 52 ); excavated Vshaped depression present, but angle of observation needs to be changed to permit clear view ( Figure 52 indicated by 5).

Circumgastric depression (s.c) easily discernible ( Figures 42 , 52, 57 indicated by l), originating slightly posterior to h.ap, with the following trajectory: lateral to la, lm, lp, h 1, h 2, and internally to h 3, p 1, p 2, p 3 ( Figures 42 , 52 ); in the posterior notogastral zone the trajectory is partially obscured by rugous elevated cuticular ridges ( Figure 57 ).

Lateral region. Dorsolaterally, lamellae clearly discernible, anterior zone welded to lateral notogastral zone, lamellar tip absent ( Figure 54 ). Tu large lamina, curving margin ( Figure 43 , 49 , 52 ). Deep s.tu.d running between and parallel to lamellae and Tu; anteriorly a large pocket depression is observed (a.tu.d); followed by deep depression, p.tu.d ( Figure 49 , 52 ). Pd I, conspicuous extended lamina, rounded apex, particular microsculpture (See Integument). Pd II medium sized, ovoid lamina; dis hardly discernible ( Figures 49 , 52 ).

Bothridia cup-shaped; bothridial opening directing slightly downwards; smooth bo.ri incomplete, with bo.to clearly discernible ( Figure 49 ).

Long, extending polyhedral humeral apophysis, rounded apex, basally undulated, anterior tip overlapping posterior bothridial part ( Figures 49 , 52 ). Series of large dep discernible behind leg IV ( Figures 49 , 52 ). Posterior notogastral zone ( Figure 57 ) with clearly visible rugous elevated cuticular ridges.

Ventral region. Epimera: central zones depressed, marginal elevated zones ( Figure 61 ). Epimera 3–4 fused, small; apo.1, apo.2, apo.sj and apo.3 well discernible ( Figure 50 ).

Epimeral chaetotaxy 1-1-3-3 (See Remarks); dis clearly observed as triangular protuberance with rounded apex ( Figure 61 ).

Genital plates small relative to anal plates; four pairs of genital setae in a simple line ( Figure 50 , 56 ); all setae more or less equal length ( Figure 56 ); ag setae far from genital opening, situated laterally and posterior to genital opening, placed on elevated rounded structure ( Figures 50 , 61 indicated by l); elevated structure covered by cerotegumental layer. Three pairs of adanal setae; ad 3 situated far from ag setae ( Figure 50 ). Anal plate rectangular to polyhedral, small sharp tip ( Figure 50 ); two pairs of anal setae. Lyrifissures not discernible. Ovoid paired depressions situated between anal and genital openings; ovoid-elongate depressions situated laterally to genital and anal openings ( Figures 50 , 61 )

Legs. Setal formulae I(1-3-2-3-16 -1) (1-2-2); II(1-4-3-3-15 -1) (1-1-2); III(2-3-1-2-14 -1) (1-1-0); IV(1-2-2-3- 13 -1) (0-1-0). Large femoral groove (Femur III).

Remarks. Epimeral chaetoxy 1-1-3-3 was observed in five specimens studied. However, due to the lengthy preservation period, the authors are uncertain if the setae have degraded during this time. There is a possibility that they exist, especially as in some instances, vestiges of setal insertions were observed. Two noteworthy aspects are: a) the large variation in shape of notogastral setae, where setae h 3, p 1, p 2, p 3 are very different to the other notogastral setae; b) the different shapes of epimeral setae, where 3b, 4b are very different compared to 3c and 4c.

Figures

FIGURES 42–48. Congocepheus thailandae sp. nov. Adult female, SEM observations. 42. dorsal anteroposterior view; 43. frontal view; 44. prodorsal in seta; 45. notogastral c 1 seta; 46. prodorsal ro seta; 47. bothridium and sensillus; 48. cuticular ornamentation of bothridium. Scale bar: 42=300 µm; 43=200 µm; 44=15 µm; 45=15µm; 46=10 µm; 47=59 µm; 48=10 µm.

FIGURES 49–51. Congocepheus thailandae sp. nov. Adult female, Optical Microscopy. 49. lateral view; 50. ventral, inclined view; 51. frontal view. Scale bar: 49=160 µm; 50=180 µm; 51=110 µm.

FIGURES 52–60. Congocepheus thailandae sp. nov. Adult female, SEM observations. 52. lateral view; 53. notogastral p 3 seta; 54. supratutorial depression and le seta; 55. subcapitulum; 56. genital plates; 57. notogaster posterolateral view; 58. subcapitular h seta; 59. subcapitular m seta; 60. ornamentation seta p 3. Scale bar: 52=200 µm; 53=15 µm; 54=59 µm; 55=25 µm; 56=59 µm; 57=30 µm; 58=10 µm; 59=10 µm; 60=5 µm.

FIGURES 61–70. Congocepheus thailandae sp. nov. Adult female, SEM observations. 61. ventrally inclined view; 62. epimeral 1a seta; 63. epimeral seta 4b, 4c; 64. epimeral 3c seta; 65. epimeral 3a seta; 66. anal seta; 67. adanal ad 3 seta; 68. aggenital seta; 69. epimeral zone, cerotegument and cuticular ornamentation; 70. detail aggenital zone cerotegument and cuticula. Abbreviations: see “Material and Methods”. Scale bar: 61:586 µm; 62:20 µm; 63:59µm; 64: 20µm; 65: 20 µm; 66:10 µm; 67:20µm;68:30 µm; 69:10 µm; 70:3µm.