Description of a new species of Julolaelaps (Acari, Mesostigmata, Laelapidae) from Iran.

Julolaelaps hallidayi sp. n., was collected from soil of river verge in Brujen, Chaharmahal va Bakhtiari province, Iran. Description and illustrations of this new species based on adult females are presented. Some entries are added to the key of Moraza and Kazemi (2012) to include the new species.

Introduction

Evolutionary relationships between mites and other arthropods date back to approximately 100 million years ago (Southwood 1973). As more niches became available, mites developed a wide variety of well-known symbiotic relationships with many arthropods (Lindquist 1975) including many species in the insect orders , , , and , and also with other arthropods such as myriapods (Farfan and Klompen 2012). The laelapid subfamily sensu Evans (1955) was promoted to family level () by Casanueva (1993) based on phylogenetic studies. The main character differentiating this family and is PageBreakthe lack of seta pl2 on genu IV in iphiopsidids (Casanueva 1993). The includes three subfamilies and ten genera of mites that are associated with millipedes, centipedes, spiders, and terrestrial crustaceans. There is little information on the biology of iphiopsidids, although based on the regressive nature of the characters it seems that they have a paraphagic or parasitic mode of life on their terrestrial arthropod hosts (Lindquist et al. 2009).

was erected by Berlese (1916) for a small group of mites living on Julids. In the definition of the genus he states that the species resemble very closely those of the genus but lack claws on all legs (Evans 1955). Vitzthum (1941) referred to Canestrini, and Berlese as members of the subfamily and Berlese and Berlese as members of the . Evans (1955) noted the possible absence of claws in all legs of (present in most ) as a generic character. Ryke (1959) introduced as a subgenus of , and described three new species while referring to the presence of small claws on leg I ambulacra. Maes (1983) described four additional species of , as a separate genus, and confirmed the presence of reduced claws on leg I.

Most species that have been reported until now are associated with small millipedes (Berlese 1916, Maes 1983, Fain 1987, Uppstrom and Klompen 2005, Kontschan 2005, Salmane and Telnov 2007, Moraza and Kazemi 2012), and a few associated with (Ishikawa 1986). The feeding habitats (parasitism or paraphagy) of are not confirmed (Salmane and Telnov 2007). Moraza and Kazemi (2012) presented a key for this genus based on known females and males, agreed the idea of Ryke (1959) to consider Vitzthum as a synonym of Berlese, 1916. The present paper is devoted to the description of a new species of , found in the soil of a river verge in Brujen, Chaharmahal va Bakhtiari province, Iran, followed by a short discussion regarding the status of correct family for this genus.

Materials and methods

Mites were collected in soil from Brujen, Chaharmahal va Bakhtiari province in Iran, extracted from samples using Berlese-Tullgren funnels, placed in lactic acid at 55 °C for clearing and then mounted in Hoyer’s medium on permanent microslides for microscopic examination. Line drawings were made by use of a drawing tube and figures were performed with Corel X-draw software, based on the scanned line drawings. Measurements of structures are expressed as minimum-maximum ranges in micrometers (µm). The dorsal setae notation followed that of Lindquist and Evans (1965). Leg and pedipalp setal notation and chaetotactic formulae are based on Evans (1963a, b respectively). Terminology for idiosomal glands and lyrifissures follows Johnston and Moraza (1991). We have attempted to identify all pore-like structures, but acknowledge that some might have been overlooked. Length of the dorsal shield is the distance from its antero-median edge anterior to bases of setae j1 to its postero-median edge posterior PageBreakto bases of setae Z5; width of dorsal shield was measured at widest part; length of the sternal shield was measured along midline from anterior edge to its posterior margin, width measured between coxae II-III (widest point) and slightly above the insertion of st2 (narrowest point); the length of anal shield is midline from the anterior margin to the posterior edge of the cribrum, and width was measured at widest point. Setae were measured at level of insertions to their tips and distance between setae as the distance between their insertions. Length of leg segments was measured dorso-medially, and tarsi were measured excluding the stalk and its appendages.

Description

sp. n.

http://zoobank.org/98513061-C2DA-41B3-80DF-E0A373F2053A

Figures 1–2 , 3–5 , 6–9 , 10–13

Figures 1–2.

sp. n. (female): 1 Dorsal idiosoma 2 Example of dorsal setae.

Figures 3–5.

sp. n. (female): 3 Ventral idiosoma 4–5 Examples of ventral setae.

Figures 6–9.

sp. n., (female): 6 Subcapitulum 7 Epistome 8 Chelicera 9 Palp.

Figures 10–13.

sp. n. (female): 10 Leg I 11 Leg II 12 Leg III 13 Leg IV.

Specimens examined.

Holotype, female, Brujen region, Chaharmahal va Bakhtiari province, Iran, soil, coll., B. Jalili, 2011; paratype, female (same data as holotype): deposited in Acarological Laboratory of Shahrekord University, Chaharmahal va Bakhtiari province, Iran; paratype, female collected from soil, Shahreza, Esfahan province, coll., F. Shameli, 2014: deposited in the Senckenberg Museum fur Naturkunde Görlitz, Germany.

Note.

Some unknown arthropods species such as members of , , and were separated associated with the soil which contained specimens of species.

Diagnosis.

Medium sized laelapid mite; with 33 pairs of simple acicular setae on dorsal shield, setae z1, z3, z6, r4, and r6 missing in podonotal part, without extra setae between J and Z series; pre-sternal area not sclerotized; genital shield with reticulated pattern possess seven closed cells with eight small indentations at their margins, cells surrounded antero-laterally by inverse V shaped lines; peritremes short, extending to posterior margin of coxae II; tibia I and III with two pl and one al respectively.

. Dorsal idiosoma oval-shaped (Fig. 1), dorsal shield covered all dorsal surface, polygonal reticulation distinct on whole dorsum except of small area around j4 and area between z5 and j6. Dorsal shield 489-567 long, 341-348 wide between of setae r3-5 (n = 3), with 33 pairs of simple acicular setae (Fig. 2), 18 pairs (j1-6, z2, z4-5, s1-6 and r2-3, r5) located on podonotum, z1, z3, z6, r4, and r6 missing on dorsal shield in podonotal part, and 15 pairs on opisthonotum (J1-5, Z1-5 and S1-5) without extra setae between J and Z series. Dorsal setae length: j1 (16-18), j2-6 (20-31), z2 and z4 (34-39), z5 (26), s1-6 (29-39), r2-3, r5 (29-36), J1-5 (20-34), Z1-5 (29- 42), S1-5 (34-39). Cuticle between dorsal and ventral side of body bent down on ventral side, and bearing R1 (18-21), R2 (21-23), R4 (23-29), R5 (23-26), R6 (26-29), and UR1-2 (23-26). Podonotal part with three and opisthonotal region with seven pairs of discernible pore-like structures, as shown in figure 1; however, it is acknowledged that some might have been overlooked.

(Fig. 3). Tritosternum with columnar base, 18–21 long, and pilose laciniae (62). Pre-sternal area not sclerotized, with lines striation. Sternal shield with thin line reticulation in lateral surfaces, 96–99 long, 148–151 wide (at level of projection between coxae II-III) and 99 slightly above the insertion of st2 (narrowest point), antero-medially slightly concave, posterior margin irregular. Sternal setae very short, st1-3 (4), smooth, with conspicuous alveoli, iv1 slit-like, located slightly behind st1, iv2 slit-like, between st2-st3. Metasternal plates absent. Setae st4 (5) and pore-like PageBreakiv3 located on integument posterior to sternal shield and interior to endopodal plates III/IV. Tongue-shaped genital shield 205–211 µm long (excluding hyaline flap at base of posterior margin of sternal shield), 83-88 wide at level of st5, and 101 at widest part near para-genital platelets, the ratio of length to width (L/W) is 2.32 /2.53 (width at level of st5), bearing one pair of setae (st5 = 4-5) and reticulated pattern with seven closed cells with eight small indentations at their margins, cells surrounded antero-laterally by inverse V shaped lines (Fig. 3), genital shield separated from anal shield by about the length of the anal opening, paragenital pore-like opening on soft integument between genital seta and coxa IV. Subtriangular anal shield reticulated, anterior margin semi-circular, 78–83 long, and 73–75 wide, with one pair of minute adanal gland pores (gv3) on lateral margins, paranal setae (10) slightly smaller than post-anal seta (13). Cribrum extending laterally slightly upper than the level of post-anal seta PageBreakinsertion. Opisthogastric surface with one pair of suboval metapodal plates, one pairs of minute platelets (between metapodal plate and para-genital platelet), one pair of narrow, slightly elongate para-genital platelets, smooth setae Jv1-3 (6-8), Jv4 (18-23), Jv5 (26), Zv1 (5-7), Zv2 (8-10), Zv3 (13-16), Zv4 (23-26), Zv5 (26-29), (Figs 4–5), and five pairs of pore-like structures. Stigmata located in anterior level of coxa IV surrounded by nearly narrow stigmatal plate. Peritremes short, extending to posterior margin of coxae II, peritrematal plate wider in anterior part, and with one glandular poroid gp (Fig. 3), separated from exopodal shield. Small poststigmatal plate with two pores. Exopodal plates like a narrow crescent-shape strip expanded posteriad coxae IV. Endopodal plates II/III fused to lateral margins of sternal shield, and III-IV elongate, narrow and angular.

. Hypostome (Fig. 6) with three pairs of smooth simple setae; h1-3 (8-10), palpcoxal setae 8-9 long. Deutosternal groove with six rows of multi-dentate (6-8 teeth), the denticles tend to be smaller from anterior to posterior rows. Corniculi normal (30-32), horn-like. Epistome with nearly smooth rounded anterior margin (Fig. 7). Cheliceral arthrodial processes crownet-like (Fig. 8), movable digit (26-29) with two teeth in addition to apical tooth, middle article 75-78 long, ending in fixed digit (29-31), bearing two teeth in addition to terminal tooth and very short setaceous pilus dentilis. Palp chaetotaxy normal for the free-living forms (sensu Evans and Till 1965), with simple and thin setae except al on femur, and al1 and al2 on genu slightly thickened; palp-tarsal claw two-tined, basal tine smaller (Fig. 9).

. Tarsi I-IV with small and not well sclerotized claws, the sclerotization status is more distinct in their tips (Figs 10–13). Leg I 374, coxa (70-73), trochanter (29-34), basi-femur (18-21), telo-femur (42), genu (42-47), tibia (55-60), tarsus (107-112); leg II 278-302 coxa (34-47), trochanter (31-39), basi-femur (16), telo-femur (34-39), genu (36-44), tibia (39), tarsus (75-91); leg III 307, coxa (36-39), trochanter (52), basi-femur (23), telo-femur (34), genu (31-36), tibia (34-36), tarsus (91); leg IV 359-385, coxa (39-47), trochanter (65-70), basi-femur (18-23), telo-femur (47-52), genu (39), tibia (44), tarsus (107-109). Legs I and IV longer than legs II and III. All leg setae smooth and pointed. Chaetotaxy of legs is as follows: Leg I: coxa 0 0/1 0/1 0; trochanter 1 0/2 1/1 1 (pl and pv slightly thickened); femur 2 3/12/2 2 (ad2, pd1 and pl2 slightly thickened); genu 2 3/1 3/1 2; tibia 2 3/1 3/1 2 (Fig. 10). Leg II: coxa 0 0/1 0/1 0; trochanter 1 0/2 0/1 1; femur 2 3/1 2/2 1 (ad1, ad3, pd1-2 and pl slightly thickened); genu 2 3/1 2/1 1; tibia 2 2/1 2/1 1; tarsus 3,3/2,3/2,3 + mv, md (al1, av1-2, pl1 and pv1-2 more thickened than the others) (Fig. 11). Leg III: coxa 0 0/1 0/1 0; trochanter 1 0/2 0/1 1; femur 1 2/1 1/0 1(ad1 thickened and ad2 slightly thickened); genu 2 2/1 2/1 1; tibia 1 1/1 2/1 1; tarsus 3 3/2 3/2 3 + mv, md (al1, pv1 and pl1 thickened). Leg IV: coxa 0 0/1 0/0 0; trochanter 1 0/2 0/1 1 (av2 slightly thickened); femur 1 2/1 1/0 1 (ad1 slightly thickened) (Fig. 13); genu 2 2/1 3/0 1; tibia 2 1/1 3/1 2; tarsus 33/23/23 + mv, md (al1 and pl1 slightly thickened).

. Not discernible.

. Unknown.

Etymology.

This species is named in honour of Dr. Bruce Halliday (CSIRO Ecosystem Sciences, Canberra, Australia).

Remarks.

The species of the genus having been reported so far can be divided into two groups: the first group consisting of 14 species with reduced number of setae on dorsal shield than sp. n. (9–23 pairs), and the other with more than 29 pairs of dorsal setae (sensu Moraza and Kazemi 2012), which comprises seven species including Berlese, 1916, Berlese, 1916, Ryke, 1959, Oudemans, 1914, Moraza and Kazemi 2012, Hunter & Rosario, 1986, and sp. n. Except for , the number of dorsal setae in the above-mentioned species is higher than in sp. n. The two latter species are different from each other in that the former has 32 pairs of dorsal setae, while the latter has 33 pairs. Furthermore, the main discrepancy between them refers to the presence of S1 in sp. n., and absence of these structures PageBreakin . In addition, has a disc-like structure on the base of tritosternum, while that structure is not present in sp. n. Leg chaetotaxy of sp. n., is different from that of Moraza & Kazemi, 2012: tibia I and III in sp. n. bears two pl and one al while in tibia I and III are with one pl and two al.

Discussion

The loss of seta pl2 on genu IV in iphiopsidids phylogenetically defines the family as an entity separate from the (Casanueva 1993), but its laelapid roots may clearly be seen in the genus , an assemblage of iphiopsidine millipede associates that had long been considered a subgenus of the broadly defined laelapid genus (Lindquist et al. 2009, Ryke 1959).

Based on Casanueva (1993) study, was recognized as a separate family from by considering two phylogenetic attributes: lack of seta av-2 on tibia I in the , and lack of seta pl-2 on genu IV in the . Assigning the new species to the family does not fit properly based on the above-mentioned attributes. In the first instance, sp. n. is defined by one apomorphic character (lack of postero-lateral seta pl2 on genu II), which has also evolved in group I () of the . Furthermore, sp. n. presents one synapomorphic character, which is a regressive autapomorphy, supporting groups I and II of the : lack of setae pv1 on genu IV. In addition, two synapomorphic characters of sp. n., the loss of setae pl2 on genu IV and the absence of podonotal setae r6, are shared with groups I-II and IV of , respectively. Finally sp. n., along with some other species of the genus , emerges from the subfamily Kramer (Casanueva 1993) by lacking two synapomorphic characters: a reduced hypostomal process and the presence of additional setae (px) between J and Z series, as well as two apomorphic characters (loss of hypostomal setae h1 or h3 on the gnathosoma and absent peritreme).

On the other hand, Lindquist et al. (2009) accepted the idea of Casanueva (1993) to consider iphiopsidids as members of a separate family from laelapid mites by referring to some characters: tibia I usually with one ventral seta, lacking seta av2; genu IV usually with one postero-lateral seta, lacking seta p12; subcapitulum with internal malae usually weakly developed, with nearly smooth lateral margins and shorter than corniculi, which is discussed below. However species of laelapid mites usually possess setae av2 on tibia I (Beaulieu 2009, Faraji and Halliday 2009, Evans and Till 1965, 1966, Kavianpour et al. 2013, Lindquist et al. 2009, Nemati and Kavianpour 2013, Nemati and Mohseni 2013), but Moraza and Kazemi (2012) considered different groups in species assemblage. Within species with edentate chelicerae in males, one group includes species with largely complete dorsal complement of setae and usually with strong neotrichy in dorsal setae on soft cuticle, a well-developed genital shield, wider than anal shield (except ), usually long peritremes (extending at least to anterior margin of coxa II), and seta av-2 present in tibia I. So, some species of possess seta av2 on tibia I and this character cannot be considered as an apomorphic feature for iphiopsidids. Furthermore, loss of seta pl2 on genua IV is a character for laelapid mites and iphiopsidids mites also exhibit this character (Beaulieu 2009, Faraji and Halliday 2009, Kavianpour et al. 2013, Moraza et al. 2009, Nemati and Kavianpour 2013, Nemati and Mohseni 2013, see also above PageBreakexplanations). In addition, Moraza and Kazemi (2012) described with subcapitular internal malae well developed, with lateral margins fimbriated and longer than corniculi.

In this research we are following Maes (1983) and Moraza and Kazemi (2012) in keeping the as a separate genus of the family Berlese, 1882, subfamily Kramer, 1886.

This research has posed questions which are in need of further investigation, and considerably more work is needed to determine the level of or as well as the name of genera that will be categorized within that level.

6	Dorsal shield with 36 pairs of setae; setae z1, z6 and S1 present; setae Z5 twice as long as j1; strong neotrichia on series R	Julolaelaps moseri Hunter & Rosario
–	Dorsal shield with 32-33 pairs of setae; setae z1, z6, r4, r6 absent and S1 present or absent	7
7	With 32 pairs of dorsal shield setae; S1 absent; tritosternal base with ventral disc-like structure	Julolaelaps tritosternalis Moraza & Kazemi
–	With 33 pairs of dorsal shield setae; S1 present; tritosternal base normal and lacks ventral disc-like structure	Julolaelaps hallidayi sp. n.