Ololaelaps Berlese, 1904: 260

Beaulieu, Frederic, Quintero-Gutierrez, Edwin Javier, Sandmann, Dorothee, Klarner, Bernhard, Widyastuti, Rahayu, Combita-Heredia, Orlando & Scheu, Stefan, 2019, Review of the mite genus Ololaelaps (Acari, Laelapidae) and redescription of O. formidabilis Berlese, ZooKeys 853, pp. 1-36 : 1

Genus Ololaelaps Berlese, 1904: 260

Pristolaelaps Womersley, 1956: 571. Synonymy by Ryke (1962).

Type species.

Laelaps (Hypoaspis) venetus Berlese, 1903

Diagnosis

(adult male and female, unless stated).Well-sclerotized hypoaspidine laelapid with a hologastric (genitiventrianal) shield in female, bearing 3-5 pairs of preanal setae (plus st5), as well as the following character states: dorsal shield covering entirely idiosoma dorsally, narrowly to broadly extending onto venter; bearing 39 or slightly fewer pairs of slender setae, including px2-3 and often one Jx. A pair of well-sclerotized presternal platelets. Female with seta st4 on sternal shield or on soft cuticle (or putatively on endopodal plate). Peritrematal shield free posteriorly or variously (narrowly) fused with hologastric and/or parapodal shields, via metapodal platelet; metapodal platelet free or variously fused to above-mentioned shields; parapodal plate well-developed, subtriangular. Soft opisthogastric cuticle with 5-10 pairs of setae. Male holoventral shield broad, fused to parapodal-exopodal plates, sometimes also to peritrematal shield. Gnathotectum convex, with few to numerous fine denticles; deutosternal groove with six rows of 1-10 denticles; female cheliceral movable digit with two teeth (rarely more), fixed digit with 3-5 (exceptionally 8); palp-apotele three-tined, third tine reduced. Leg chaetotaxy normal for Laelapidae ; setae generally slender.

Description.

Dorsal idiosoma.Dorsal shield relatively large (435-800 in female), broadly oval to narrowly suboval (length/width ratio 1.2-1.8), completely covering idiosoma dorsally, barely to moderately extending ventrally (this can be determined most accurately before slide-mounting); shield smooth (except for fine granulation or punctuation) to strongly reticulate; shield’s ventral extension ( ‘epipleura’ of Bregetova and Koroleva (1964)) smooth to reticulate (sometimes in contrast to smooth dorsal region of shield); shield with a delineated marginal strip along its edge. Dorsal shield bearing 39 pairs of simple, slender, almost hair-like setae, short to moderately long, including px2-3, and often one unpaired median seta (Jx) inserted at a level between J2 and J3 (Table 2); sometimes fewer than 39 pairs of setae, with z1 (absent in O. sellnicki ), z3 (see Evans and Till 1966), or setae in r or S series apparently absent; shield never hypertrichous; setae slender and smooth, occasionally with a few light barbs on Z5 and J5 ( Jordaan and Loots 1987). Shield with 16 pairs of poroids and four or five pairs of gland openings (based on Bregetova and Koroleva (1964) and specimens examined, representing a few species only): gd1, gd2 (sometimes absent), gd4 (usually conspicuous, on or near shield margin), gd6, gd9.

Ventral idiosoma.Tritosternum normal, with two pilose laciniae. Presternal region with a pair of sclerotized platelets, wedge-shaped to subrectangular, lineate (typically with 2-4 transversal lineae); typically an additional, poorly sclerotized area, lineate and granulate, anteriorly or anteromesally adjoining each platelet. Female sternal shield as long as or longer than wide, sometimes wider than long; shield length/width ratio 0.6-1.8; Shield posterior margin straight, slightly to moderately concave, or sometimes convex; shield reticulate, smooth in its posterior fourth or fifth, bearing 3-4 pairs of simple setae and 2-3 pairs of poroids, therefore sometimes including seta st4 and poroid iv3; seta st4 on sternal shield (near or on its posterolateral edge), on soft cuticle, or apparently on endopodal plate (Table 2; see Discussion). Female hologastric shield broad, laterally extending to or beyond margin of parapodal (or adcoxal, Bregetova (1977a)) plate, overlapping sternal and endopodal shields, bearing usually five pairs of preanal setae (JV1-3, ZV1-2) in addition to seta st5, occasionally only three or four pairs of preanals (JV3 and/or ZV2 off shield) or exceptionally six (ZV3 apparently on shield in O. rectagoni ); shield setae usually moderately long, sometimes short; hologastric shield ornamented with reticulation, cells polygonal, scale-like or elongate transversally (note that shield reticulation is not drawn for some species in Ryke (1962), but probably present; compare O. mooiensis in Ryke (1962) vs Marais and Loots (1972)); circumanal setae shorter than preanals, and postanal usually shorter than paranal setae; cribrum typically with 2-3 rows of spicules. Endopodal plate besides coxae III–IV well-developed (appears reduced in O. dililoensis , but the portion of endopodal plate that is overlapped by hologastric shield may have been overlooked); plate free, more or less contiguous with sternal shield (or apparently fused to it, e.g., O. expansus ( Ma 2015)) or slightly overlapped by it. Peritrematal shield well-developed, fused to dorsal shield anteriorly, usually free posteriorly, reaching approximately posterior margin of coxa IV, occasionally only mid-coxa IV, or moderately surpassing coxa; sometimes narrowly connected to hologastric shield and/or parapodal element; peritrematal shield posteriorly bifid in some species ( O. interruptus , O. leptochelae , and an undescribed species from North America). Peritreme narrow, usually reaching anteriorly level of coxa I, sometimes slightly less. Parapodal plate well-developed, subtriangular, with outer margin convex (especially when peritrematal shield free and not extending beyond coxa IV) or straight (typically when peritrematal shield extended posteriorly or fused to hologastric shield); parapodal exceptionally not produced in O. rectagoni (Table 2) and an undescribed species from Costa Rica; parapodal posteriorly free, more or less abutting hologastric shield, or narrowly fused to hologastric and/or peritrematal shields, via metapodal element as connecting ‘bridge’. Metapodal platelet entirely free, suboval to strip-like, or variously fused to hologastric shield, parapodal and/or peritrematal plates. Exopodal strip well-developed, fused to parapodal element posteriorly, and anteriorly to sternal shield between coxae I–II. Soft opisthogastric cuticle surrounding shield with 5-10 pairs of simple setae, often including 1-2 pairs of r-R setae isolated at level near parapodal plate; never hypertrichous. Male holoventral shield fused to parapodal-exopodal elements, sometimes also to peritrematal shield, bearing 3-5 preanals (JV1-3, ZV1-2; JV3 and ZV2 sometimes off shield, e.g., O. ussuriensis ); metapodal element merged with holoventral shield.

Gnathosoma.Gnathotectum with subtriangular to rounded margin, usually finely denticulate, may appear smooth when denticles sparse or (possibly) absent. Deutosternal groove of moderate, regular width, or slightly tapering posteriorly, with six (occasionally seven, and rarely five) rows of denticles, each row bearing 1-10 denticles, most of the rows with 3-7 denticles; denticulate rows usually preceded by a smooth ridge anteriorly, and sometimes also posteriorly. Corniculi horn-like, of moderate length. Internal malae with two pairs of long projections, median pair fimbriate on its basal portion, lateral pair smooth or branched or fimbriate in its apical portion; lateral projection absent in males (and apparently in the female of O. sitalaensis ). Palptarsal claw three-tined, third tine reduced. Chelicerae of moderate length, chelate-dentate; female movable digit with two moderately-sized teeth, rarely more (two additional small teeth between the two typical large teeth in O. interruptus ; Table 2); fixed digit with 3-5 teeth, variously sized, rarely more (eight in O. leptochelae ), including a subapical, laterally offset tooth (gabelzhan); male digits each with a single tooth; pilus dentilis setiform; arthrodial process a simple corona. Male spermatodactyl 0.7-2.0 × as long as movable digit, from its departure from edge of digit; more or less straight or variously bent; junction between spermatodactyl and movable digit straight to strongly angled ( O. translineatus ); duct inside spermatodactyl straight or sinuous. Chaetotaxy of subcapitulum and palps normal for Laelapidae (sensu Evans and Till 1965).

Legs.Chaetotaxy normal for Laelapidae (sensu Evans and Till 1965); most setae slender; ventral and/or subapical setae of tarsi II–IV usually moderately thickened, sometimes lateral setae too (e.g., al2, pl2-3 of tarsus IV); setae on other leg segments occasionally thickened (e.g., pd2, ad3 on femur I, pd on femur III in O. placentula ; also dorsally on femur IV in O. mooiensis ( Jordaan and Loots 1987)). Males of some species with a spine-like seta on femur II ( O. translineatus ); pv thickened on genu or tibia III (in undescribed species); a ventral spine on tarsus II, apparently representing pv2 (position shifted proximad) (e.g., O. venetus , O. placentula , O. ussuriensis ); or with cuticular tubercles on various leg segments (femur and genu of O. placentula , O. ussuriensis ). Ambulacra I–IV with well-developed paired claws and pulvillus.

Spermatheca.

Spermathecal ducts well-sclerotized and discernable in some species.