A Review of the Feather Mite Genus Lopharalichus Gaud & Atyeo, 1996 (Acariformes: Pterolichidae), with Descriptions of Three New Species from Brazilian Parrots (Psittaciformes: Psittacidae)

Simple Summary Understanding the current biodiversity of our planet is an ongoing challenge, as natural habitats are being destroyed at a faster rate than species are described. This is especially true for South America, which harbors over one-third of the parrot species in the world. A diverse yet poorly studied group of mites associated with birds are feather mites, which currently include about 2500 known species, and estimates range from 10,000 to 20,000 species. Herein, three new species of feather mites of the genus Lopharalichus are described from parrots in Brazil. Abstract Feather mites of the genus Lopharalichus Gaud & Atyeo, 1996 (Pterolichidae: Pterolichinae), formerly containing three described species, are associated with New World parrots (Psittaciformes: Psittacidae) of the subfamily Arinae. Three new species of this genus are described: Lopharalichus tuim sp. nov. from Forpus xanthopterygius (Spix, 1824), L. spinosus sp. nov. from Ara ararauna (Linnaeus, 1758), and L. chiriri sp. nov. from Brotogeris chiriri (Vieillot, 1818). Type specimens of the previously described Lopharalichus species were examined, and a key to the known species is provided.

The most distinctive feature of the genus Lopharalichus is the presence of prominent spiny crests on the femora and genua of legs I and II of both males and females, after which the genus was named (Gr. lophos = crest, mane). Other noticeable features are as follows: in both sexes, the lateral regions of hysterosoma have small cuticular spines, setae c2 are bifid, scapular setae si are subequal to or longer than setae se, setae se are very short (at maximum

Materials and Methods
The new mites studied herein were collected from either wild bird specimens found dead in the field or from taxidermied bird specimens (see below). In the former case, the birds were collected and frozen for a later study; in laboratory, they were washed in a plastic tray with water and detergent to remove the ectoparasites [9], and the water was filtered through a paper filter. The mites were collected from the filters with a fine brush under a dissecting microscope. A few specimens from Ara ararauna (Linnaeus) were also retrieved from dry museum skins deposited at the Museu de História Natural Capão da Imbuia (MHNCI), Curitiba, following the ruffling technique described in Gaud & Atyeo [5]. The mites obtained with both methods were cleared and distended in 30% lactic acid at 50 • C for 24 h, mounted on microscopic slides using Hoyer's medium [10], and heated and dried at 50 • C for 5 days. Finally, the edges of the coverslips were sealed with transparent varnish and the slides were labeled. The specimens were studied under an Olympus CX31 microscope, and illustrations were prepared from pictures of the mites taken with a digital camera (Omax A35140U 14mpx, Chengdu, China) attached to the ocular lenses and produced on Adobe Illustrator CS5 using a Wacom Bamboo Create tablet. The chaetotaxies of idiosoma and legs follow Griffiths et al. [11] and Atyeo & Gaud [12], respectively, with further corrections for coxal setae [13]. The nomenclature of birds is according to Gill et al. [14].
The species descriptions are given according to the formats proposed by Mironov et al. [6] and Hernandes [4]. Type specimens of the new species are deposited at the Acari Collection of the Department of Ecology and Zoology of the Universidade Federal de Santa Catarina, Florianópolis (ECZ-UFSC). Additional material examined consisted of types and other specimens of Lopharalichus cribriformis and L. denticulatus determined by W.T. Atyeo and are deposited at the Trouessart collection of the Muséum National d'Histoire Naturelle (MNHN), Paris, France. Photos of non-type specimens of L. beckeri deposited at the Zoology Institute, Russian Academy of Sciences (ZISP), St. Petersburg, were also examined.            Remarks: Lopharalichus denticulatus stands out from other species in having, in males, setae ps1 roughly triangular, setae e2 simple and not bifurcate basally; in females, the prodorsal setal pair si is well spaced by about three-times the distance si:se ( Figure 3A); in both sexes, vertical setae vi are slightly expanded (Figures 2A and 3A), genua I, II have prominent, thick antiaxial crests, and the hysteronotal shield is usually devoid of lacunae; in one non-type male examined, there are a few small, sparse circular lacunae in the center of the shield, about 1-3 µm in diameter. The only examined female is broken, with legs, epigynum, and other structures displaced from their original position.

Results
Lopharalichus  Remarks: Lopharalichus cribriformis is very similar to L. beckeri Mironov et al. (2005), differing from that species in having, in males, the terminal cleft angular and the paragenital apodemes indistinctly developed, and in females, setae si distinctly longer and more robust than se (at least twice longer and twice thicker) ( Figure 3B), and the solenidion on tibia IV as long as half the width of this segment ( Figure 5F). In males of L. beckeri, the lobar cleft is nearly semicircular ( Figure 1C), and the paragenital apodemes are distinctly formed; and in females, setae se and si are both piliform and similar in structure ( Figure  3C), and solenidion φ on tibia IV is about the same length as the width of tibia ( Figure  5G).
Mironov et al. [6] stated that, in males of L. cribriformis, setae e2 are twice as long as  Remarks: Lopharalichus cribriformis is very similar to L. beckeri Mironov et al. (2005), differing from that species in having, in males, the terminal cleft angular and the paragenital apodemes indistinctly developed, and in females, setae si distinctly longer and more robust than se (at least twice longer and twice thicker) ( Figure 3B), and the solenidion on tibia IV as long as half the width of this segment ( Figure 5F). In males of L. beckeri, the lobar cleft is nearly semicircular ( Figure 1C), and the paragenital apodemes are distinctly formed; and in females, setae se and si are both piliform and similar in structure ( Figure 3C), and solenidion ϕ on tibia IV is about the same length as the width of tibia ( Figure 5G).
Differential diagnosis: The new species, L. tuim sp. nov., is very close to L. cribriformis (Mégnin & Trouessart, 1884) described from Forpus passerinus in having a blunt-angular terminal cleft in males. In males of L. denticulatus and L. beckeri, the lobar cleft is concave and semi-circular. The new species most clearly differs from L. cribriformis in the relative length and arrangement of prodorsal setae si: in females of L. tuim sp. nov., si reaches the base of se of the same side ( Figure 3D), and in males, si reaches at least halfway to the base of corresponding setae se, si being about twice longer than se ( Figure 2D). Also, in males of the new species, setae si are inserted slightly closer to the corresponding se than to the other member of the pair si (distance si:si is about 1 1 2 the distance si:se). In L. cribriformis females, setae si only reach about halfway to the bases of corresponding se ( Figure 3B), and in males of that species, these setae reach one-third of that distance (si is about the same length as se) ( Figure 2B), and in both sexes, the scapular setae si and se are uniformly spaced (distance si:se = si:si).
Etymology: The name of the new species is based on the Brazilian common name of the host (tuim) and is a noun in apposition.
Differential diagnosis: Lopharalichus spinosus sp. nov. is close to L. beckeri and L. cribriformis in having, in males, well-formed cuticular spines in the lateral part of idiosomal anterior to setae e2. In both sexes of L. spinosus, however, those spines are much more numerous and occupy a larger area, from the level of setae cp to that of setae e2; in addition, in males of the new species, scapular setae si are spiculiform, noticeably more robust than se ( Figure 2E). In both sexes of L. beckeri and L. cribriformis, the lateral spines are present only from the level of trochanter IV to the level of setae e2. In males of L. cribriformis and L. beckeri, and in females of the latter species, both scapular setae si and se are thin piliform ( Figure 2B,C and Figure 3C); in females of L. cribriformis, setae si are more robust than se, but they only reach halfway to the distance between those setae ( Figure 3B), whereas in L. spinosus sp. nov. females, si reaches the bases of corresponding setae se ( Figure 3E).
Etymology: the specific name is an adjective (masculine) referring to the numerous cuticular spines on the lateral margins of hysterosoma, more pronounced and numerous than in other known species.
Lopharalichus chiriri sp. nov. (Figures 1F, 2F, 3F and 12, Figures 13 and 14) Animals 2023, 13, x FOR PEER REVIEW 15 of 22     Differential diagnosis: Lopharalichus chiriri sp. nov. is very similar to L. cribriformis due to the blunt-angular shape of terminal cleft in males but can be distinguished by the relatively longer distance between prodorsal setae si-si. In males of the new species, this distance is about 3.5-times the length of setae si, against 2.5-times that length in L. cribriformis. Also, the new species has smaller dorsal lacunae and relatively shorter solenidion on tibia IV in males, reaching only about half of the length of tarsus (it reaches at least 3 /4 of tarsus length in L. cribriformis). The new species is also distinguished from all previously known species in having, in both sexes, considerably longer solenidion on tibia III, roughly longer than the length of genu and tibia III combined. In females of L. chiriri, setae si are relatively shorter, their tips not touching each other ( Figure 3F), while in L. cribriformis females, these setae do touch each other. Additionally, in both sexes of L. chiriri, tibial solenidion ϕIII is equal to the length of genu + tibia III ( Figure 14C,H), while in other known species of Lopharalichus, solenidion ϕIII is shorter than the length of corresponding genu and tibia.
Etymology: the specific name is a noun in apposition referring to the species name of the type host.
3': In both sexes, spines on the lateral margins of hysterosoma limited to the levels between setae d1 to e2 (in males), and d1 to f 2 (in females) . . . . 4 4. In both sexes, solenidion ϕIII longer or equal to the length of genu + tibia III ( Figure 14C,H); in females, tips setae si not reaching each other . . . . L. chiriri sp. nov. 4'. In both sexes, solenidion ϕIII shorter than the length of genu + tibia III; in females, setae si relatively longer, their tips touching each other . . . 5 5. In both sexes, distance si:si about 1.5 longer than distances between si:se ( Figures 2D  and 3D); in males, si about twice longer than se; in females, setae si equal to distance si:se . . . .. L. tuim sp. nov. 5' In both sexes, distance si:si approximately equal to the distance si:se ( Figures 2B and  3B); in males, si and se subequal in length; in females, setae si shorter than the distance between setae si and se . . . .. L. cribriformis (Mégnin & Trouessart, 1884)

Discussion
By the time Gaud & Atyeo [5] established the genus Lopharalichus, they mentioned that it occurred solely on parrots of the subfamily Aratinginae (sensu Wolters [18]). However, they also referred to this genus as having two undescribed species [5] from parrots then considered in the subfamily Forpinae (sensu Wolters): Forpus passerinus and F. sclateri (the latter is currently regarded as a subspecies of Forpus modestus (Cabanis, 1849)). Herein, a new species is described from the genus Brotogeris, previosuly considered in yet another subfamily of Wolters, Brotogerinae. In the current classification of parrots [19], the hosts of Lopharalichus are parrots of the family Psittacidae, subfamily Arinae, tribes Arini, Forpini, and Androglossini-it remains to be discovered whether Lopharalichus is also present on the tribe Amoropsittacini. Those three tribes account for nearly 140 parrot species (~93% of the arine species), and Lopharalichus spp. has been reported from only eight of those hosts so far, including two undescribed species illustrated by Gaud & Atyeo [5].
According to Wright et al. [20], the Arinae-the New World parrots-diverged from the African Psittacinae around the K-T boundary (~66 mya) and diversified approximately 55 mya. Lopharalichus, being found only in New World parrots, probably originating between those dates, and given its seemingly uneven distribution on three out of four arine tribes (see above), it probably independently colonized those hosts horizontally rather than vertically. Recent studies have demonstrated that horizontal transfer is an important means of colonizing new hosts e.g., [21,22]. An alternative but less likely scenario would be Lopharalichus being present on the arine ancestor and having independently become extinct from several hosts of the tribe Arini (e.g., Anodorhynchus Spix, Cyanopsitta Bonaparte, Deroptyus Wagler, Diopsittaca Ridgway, Enicognathus Gray, Leptosittaca Berlepsch & Stolzmann, Pionites Heine, and Pyrrhura Bonaparte) and Androglossini (most genera excepting Brotogeris, see [19]). In a series of papers, W.T. Atyeo and co-workers investigated the pterolichine feather mites from several of those Arini hosts and did not retrieve any mites that would be later classified in the genus Lopharalichus [23][24][25][26][27][28]. Valdebenito et al. [29] examined feather mites from the two species of Enicognathus from Chile (also belonging to the Arini) and did not retrieve Lopharalichus. As for the tribe Androglossini, only one Lopharalichus is known, L. chiriri sp. nov. from Brotogeris chiriri; the latter tribe contains 10 genera and at least 66 species [14]. Since many of those hosts have not been thoroughly investigated for feather mites, it is reasonable to anticipate that other Lopharalichus species may be present in some of those hosts. In the past decade, only a few studies have examined feather mites associated with psittaciform birds in Brazil e.g., [4,[30][31][32][33][34]. It is clear, however, that several species remain to be discovered, as nearly 90 parrot species (Psittacidae: Arinae) are found in the country [35].
As in other genera of the Protolichus group, the solenidion σ1 of genu I in Lopharalichus is highly reduced, vestigial, and depending on the position of the specimen on the slide, barely visible. Although the presence of this solenidion was confirmed for some Lopharalichus species (e.g., L. cribriformis, L. beckeri, and L. spinosus sp. nov.), it was not possible to confirm its presence in the remaining species studied.
Despite the presence of cuticular spines in the adults, the two examined immature specimens belonging to the species described herein lack such spines. The retention of small cuticular spines on the posterolateral margins of opisthosoma in most adults of Lopharalichus species (except in L. denticulatus) is not unique to this genus. In other pterolichines belonging to the Protolichus generic group, like Aralichus Gaud, 1966 and Distigmesikya Atyeo, Gaud et Pérez, 1984, the immatures have numerous such spines-in Aralichus, they are mostly located caudally, and in Distigmesikya, they abundantly cover most of the dorsum) [5,25]. As these mites undergo their final moult to adulthood, those spines disappear in most species. In some of them, however, spines are present in adults, like in both sexes of Aralichus glaucogularis Atyeo et Pérez, 1990, and in females of Scolaralichus vazquezae Pérez et Atyeo, 1986, Aralichus menchacai Pérez et , and Tanyaralichus elongatus Pérez et . However, the immatures of the latter two species were not illustrated with cuticular spines [23,24,28].

Conclusions
With the description of three new species, Lopharalichus has effectively doubled its known species count, now encompassing six species: L. denticulatus (Mégnin & Trouessart, 1884) (type species), L. cribriformis (Mégnin & Trouessart, 1884), L. beckeri Mironov et al. 2005, L. tuim sp. nov., L. spinosus sp. nov., and L. chiriri sp. nov. However, since most neotropical parrots remain uninvestigated for their feather mites, it is safe to assume that many other Lopharalichus species may exist and will eventually be discovered.