Research Article |
Corresponding author: Nestor Fernandez ( nestorfernand51@yahoo.fr ) Academic editor: Vladimir Pesic
© 2018 Nestor Fernandez, Pieter Theron, Sergio Leiva, Anine Jordaan.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Fernandez N, Theron P, Leiva S, Jordaan A (2018) The family Lohmanniidae (Acari, Oribatida) II: two new Oribatid mites, Meristacarus perikopesis sp. n. from Costa Rica and Torpacarus eidikoterai sp. n. from Kenya. ZooKeys 743: 43-66. https://doi.org/10.3897/zookeys.743.22815
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Two very particular new species of the family Lohmanniidae were studied and described using optical and Scanning Electron Microscopy (SEM). Meristacarus perikopesis sp. n. displays complex cuticular microsculpture with cross-shaped grooves and pusticulate porose areas; ten transversal bands, with reticulate-foveate microsculpture; S4, S5, S7, S10 not crossing medial notogastral plane, amongst other characters. Torpacarus eidikoterai sp. n. with: prodorsum - rostrum weakly bilobate with small central structure and CSO present. Six transversal depressions present, transversal bands absent; but six transversal depressions present, none of the depressions crossing medial notogastral plane.
Costa Rica, Kenya, Lohmanniidae , systematics
In this paper we continue our study of material collected in the Turrialba forest of Costa Rica, and embark on the analysis of an extensive collection of material from Kenya. A brief discussion of previous studies of these genera is given below.
The genus Meristacarus was discovered and described by Grandjean in 1934 and today consists of more than fifteen species and three subspecies with worldwide distribution (Subias 2017). Authors contributing further knowledge include
The genus Torpacarus was described by Grandjean in 1950 and comprises 14 species worldwide (Subias 2017) studied by amongst others:
Two studies by
Specimens studied by means of optical microscopy followed the techniques described by Grandjean (1949) and
Optical drawings should be considered semi–schematics with regard to cuticular microsculpture and setal shapes. SEM micrographs provide much higher levels of precision and detailed figures.
Body measurements taken: total length (tip of rostrum to posterior edge of notogaster); width (widest part of notogaster). All measurements given in micrometers (μm). Measurements of setae taken on three specimens (SEM); length of setae are to be considered provisional as, though preservation was good, these mites were preserved in alcohol for over 35 years and possible damage to setal tips cannot be excluded.
Optical microscopy (standard, polarized and phase contrast) was used during leg chaetotaxy studies. Setal formulae of the legs include the number of solenidia (in parentheses); tarsal setal formulae include the famulus (ε).
Morphological terms and abbreviations used are those developed by Grandjean (1928–1974) (cf.
Additional abbreviations for Torpacarus seidikoterai: at anterior transversal depression; mt1 medial transversal depression, situated posterior to mt; pt2 posterior depression situated behind pt depression.
Institution abbreviation. MNHG: Museum of Natural History, Geneva, Switzerland.
The specific epithet perikopesis is derived from perikopés, (Περικοπές in Greek meaning cuts in English) by the characteristic cross-cut grooves present on the cuticle.
Holotype.♀“CR 0978 Tu 15 Costa Rica Turrialba foret naturelle du Catie alt.560 m. Triage d’humus pied arbre à contreforts. 11. IX. 1978. LEG P.WERNER”; material conserved in 70 % ethanol, deposited in MHNG. Paratypes. 2 ♀♀, same data and locality, deposited in MHNG; preserved in 70 % ethanol.
(adult female). Integument. Very complex with irregular cross-shaped grooves on prodorsum and notogaster. Smooth surfaces: anterior zone prodorsum extending to rostrum; zone posterior to b.sj; subcapitulum; anterolateral zone of prodorsum; epimeral zones; genital plate; preanal plate. Pusticulate surfaces (porose areas) on prodorsum, notogaster. Reticulate–foveate: Sb, S1, S2, S3, S4, S5, S6, S7, S8, S9, S10 transversal bands, notogaster. Colliculate: basal subcapitulum region; areas surrounding 1a epimeral setae; v.sj; anal-adanal zone and BPDA; legs I, II, III, IV. Undulate on lateral epimeral zone. Punctate: entire prodorsum and notogaster. Sulcate: bothridial ring.
Prodorsum. Flat smooth chitinous edge, external to exa, exp, and le setae, postbothridial transverse band sb hardly discernible.
Notogaster. Sixteen pairs of primary notogastral setae: c1, c2, c3, d1, d2, d3, e1, e2, f1, f2, h1, h2, h3, p1, p2, p3;tentransversal bands: S1, S2, S3, S4, S5, S6, S7, S8, S9, S10. Transversal bands S4, S5, S7, S10 not crossing medial notogastral plane; prodorsal, notogastral setae barbate; adoral setae: or1 large, teardrop-shaped; or2 elongate, wide acutely terminating tip; or3 long, thin, sharply tipped.
(Adult female).Measurements 887 (876–920) × 376 (351–386) μm (n: 3).
Shape. Oval (Figure
Colour. Yellow to light reddish yellow; slightly shiny when observed in reflected light.
Meristacarus perikopesis sp. n. Adult with cerotegumental layer. SEM micrographs. 1 dorsal view 2 dorsal prodorsal margin 3 notogastral setae, lateral view 4 cuticular microsculpture 5 sensillus, general view 6 bothridium detail 7 cuticular microsculpture, high magnification. Abbreviations: See “Material and methods”. Scale bars: 500 μm (1); 20 μm (2); 50 μm (3); 30 μm (4); 100 μm (5); 6 20 μm (6); 2 μm (7).
Cerotegument. Mostly absent, on some regions (e.g., near the bothridium (Figure
Integument. Very complex. Irregular cross-shaped grooves (Figures
Setation (legs not included). Simple, smooth: epimeral (Figures
Prodorsum. Shape: triangular, rounded apex in dorsal view (Figures
Bothridium (bo) ring-shaped, rounded, with particular microsculpture slightly elevated from the cuticular surface (Figures
Notogaster. Sixteen pairs of primary notogastral setae clearly discernible: c1, c2, c3, d1, d2, d3, e1, e2, f1, f2, h1, h2, h3, p1, p2, p3 (Figures
Five pairs of lyrifissures present: ia, ip, im, ips, ih; ips situated on adanal fold band (BPDA) (Figure
Lateral region. In lateral view certain transverse bands are hardly discernible, principally S8, S9, S10 (Figure
Ventral region. Subcapitulum more or less triangular, posterior zone ovoid. Four pairs of subcapitular setae, a, m1, m2, h. Smooth elevated triangular structure (Figure
Adanal plate with four pairs of setae (Figure
Legs. Two types of femora can be distinguished. Femora legs I and II displaying large ventral blade (Figure
The porose area indicated by
Our results are markedly different to
Meristacarus perikopesis sp. n. Adult female with cerotegumental layer. SEM micrographs. 23 leg IV paraxial view 24 leg II paraxial view 25 leg III 26 apical zone, leg II 27 ventral apical zone, leg II 28 tarsus I, famulus and solenidion zone. Scale bars: 50 μm (23–25); 20 μm (26); 5 μm (27, 28).
The specific epithet eidikoterai is derived from eidikótera (ειδικότερα in Greek meaning particular in English), due to specimen characteristics.
Holotype. ♀ Female KEN 77-42. Tana. River distr. Lac Shakababo près de Ngao. Tamisage broussailles avec des cactées. 28. X. 1977. LEG. V. Mahnert & J.L. Perret“. Material deposited in the Collection of the Museum of Natural History, Geneva. Paratypes. same data, 2 ♀♀ deposited in MHNG; preserved in 70 % ethanol.
Microsculpture. Areolate: prodorsum, except for CSO zone; entire notogaster lateral to BPAD; near setal insertion p2, p3 extending to acetabulum IV; epimeral zone. Smooth: anterior prodorsal zone of CSO; anterior notogastral zone; anterior epimeral zone; central epimeral zone behind v.sj furrow; internal preanal zone; adanal plate. Colliculate: epimeral zone at level of acetabulum IV; around 4a epimeral setal insertion; lateral adanal zone and BPAD; elevated ridges on genital plate. Prodorsum. Rostrum weakly bilobate with small central structure; elevated smooth longitudinal zone with CSO; externally to exa, exp, le and ro setae, flat elevated margin extending dorsally, terminating near rostrum; ovoid ring-shaped bothridium, lateral opening; internal bothridial ring pronounced on cuticular surface; sensillus bipectinate; postbothridial transverse band sb forming shallow groove, transversal prodorsal band sb present. Notogaster. Sixteen pairs of primary notogastral setae: c1, c2, c3, d1, d2, d3, e1, e2, f1, f2, h1, h2, h3, p1, p2, p3; setae c1,c2 d1, d2 ,e1 either with few barbs, or nail-shaped. Transversal bands not observed, six paired depressions at, mt; nt, pt, mt1, pt2 present, depressions not crossing medial notogastral plane. Ventral region. Epimeral setal formulae (3-1-4-4).
Description.Measurements.SEM 756 (727–780) × 337 (281–400) μm (n: 8). Light microscopy: 775 (751–811) × 342 (334– 403) μm (n:4).
Shape. Elongate-oval (Figures
Colour. Specimens without cerotegument: brown-light red; slightly shiny when observed in reflected light.
Cerotegument. Not detected.
Integument. Microsculpture varying according to body region: areolate (Figures
Torpacarus eidikoterai sp. n. Adult female with cerotegumental layer. SEM micrographs. 29 dorsal view 30 lateral view, interlamellar setae and sensillus 31 rostral setae 32 c1 notogastral setae 33 c1 notogastral setae, variations 34 notogastral setae, lateral view. Scale bars: 100 μm (29); 30 μm (30); 40 μm (31); 10 μm (32); 10 μm (33); 10 μm (34).
Setation (legs not included). Two types of setae: smooth and barbate: subcapitular setae a, adoral setae, or1, or2, or3 (Figures
Prodorsum. Polyhedral in dorsal view, between bng and le setal insertion levels (Figure
Ovoid, ring-shaped bothridium (bo), slightly elevated from cuticular surface (Figures
Notogaster. Sixteen pairs of primary notogastral setae: c1, c2, c3, d1, d2, d3, e1, e2, f1, f2, h1, h2, h3, p1, p2, p3 clearly discernible (Figures
Three other depressions: at situated behind c2, c3setal insertions; mt1 situated parallel to mt; pt2 only visible in ventro posterior-anterior (Figure
Five pairs of lyrifissures present: ia, ip, im, ip, ih and ips; im behind d2, d3 (Figure
Posterior anterior view. Dorsoposterior-anterior view (Figure
Ventral posterior-anterior view (Figure
Lateral region. Only transversal prodorsal band sb and notogastral depressions mt1, pt, pt2 (Figure
Ventral region. Subcapitulum polyhedral, posterior zone ovoid; spur visible behind subcapitular setae m2 insertion level, in marginal position (Figure
Adoral setae (Figures
Coxisternal region divided into two parts by ventrosejugal groove (Figures
Torpacarus eidikoterai sp. n. Adult female with cerotegumental layer. SEM micrographs. 47 epimeral zone 48 adanal setae 49 genital setae, variation 50 genital setae 51 genital plate 52 anogenital zone. Scale bars: 200 μm (47); 50 μm (48); 7 μm (49); 7 μm (50); 100 μm (51); 100 μm (52).
Legs (Figures
Porose areas were not observed. Shallow depressions indicated by
Meristacarus perikopesis sp. n. is close to Meristacarus porcula Grandjean, 1934. Some characters were compared using optical microscopy, while detailed observations using SEM aided in providing certainty in comparison of structures. A series of shared characters were observed such as: body shape; numerous porous areas on prodorsum, notogaster and epimeres (“pusticulate surfaces” see Remarks); presence of ten transversal bands. Some observed differences in comparison to other congeners: shape of porose areas; differences in position of prodorsal in setae, which in Meristacarus perikopesis sp. n. are situated near bo and on the sb band; large smooth zone in front of S1 and b.ng; barbate prodorsal and notogastral setae; transversal bands S4, S5, S7, S10 not crossing medial notogastral plane; differences in shape of adoral setae or1.
Adequately comparing Torpacarus eidikoterai sp. n. is impeded by the lack of detailed figures, besides dorsal and ventral views, in descriptions of other congeners. The shape of the prodorsum in Torpacarus eidikoterai sp. n. differs from all fifteen other species with the exception of T. gramineus McDaniel, Norton & Bolen, 1979 (figure 4 page 627) where the rostrum appears bilobate, though the authors did not note this in text.
Other important aspects for comparison include the sizes of some central notogastral setae, and the transversal lines (or depressions). Setae c1, c2, d1, d2, e1 are small in T. eidikoterai sp. n and at, mt, mt1, nt, pt, pt2 transversal depressions are present. This can be compared to: T. foveolatus Wallwork, 1962, with small c1, d1, d2, e1 setae and medium sized c2, f1, h1, where all setae are mostly smooth (occasionally with barbs), and transversal lines are not present. T. magnus Wallwork, 1962 presents small setae c1, d1, d2, e1 with other setae of normal size, and only transversal line mt present; T. cinctus Wallwork, 1962, small setae c1, d1, d2, e1, transversal lines mt and nt present; T. omittens Grandjean, 1950, setae c1, d1, e1small;transversal lines mt, nt, pt present. Finally T. remotus Schatz, 1994 with small c1, c2, d1, d2, e1 and medium sized f1, h1 setae; transversal bands mt, nt, pt present. The ensemble of characters clearly distinguishes Torpacarus eidikoterai sp. n. from other congeners.
This work is based on research supported in part by the National Research Foundation of South Africa (UID) 85288. Any opinion, findings and conclusions or recommendations expressed in the material are those of the authors and therefore the NRF does not accept liability in regard thereto.