Research Article |
Corresponding author: Omid Joharchi ( j.omid2000@gmail.com ) Academic editor: Farid Faraji
© 2016 Omid Joharchi, Esmaeil Babaeian, Alireza Jalalizand.
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:
Joharchi O, Babaeian E, Jalalizand A (2016) Review of the genus Laelaspisella Marais & Loots, with the description of a new species from Iran (Acari, Laelapidae). ZooKeys 549: 13-22. https://doi.org/10.3897/zookeys.549.6939
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A new species of mite is described from Iran, Laelaspisella elsae sp. n. (Acari: Laelapidae). The new species was collected from bark of elm trees in Isfahan province. A revised diagnosis for Laelaspisella, as well as a key to the world species of the genus, are presented. Two species groups of Laelaspisella are proposed: those with seta pd3 on genu I and those without pd3 on genu I. Pseudoparasitus (Gymnolaelaps) tonsilis Karg, 1989a is transferred to Laelaspisella, based on its hypertrichous holodorsal shield, metasternal setae st4 absent and genu IV with ten setae. The problems with L. canestrinii are explained and L. canestriniisensu
Laelaspisella , Laelapidae , elm trees, Isfahan, Pseudoparasitus (Gymnolaelaps) tonsilis Karg, Iran
The genus Laelaspisella Marais & Loots, 1969 was described for two species found in soil in southern Africa. Laelaspisella was considered as a subgenus of Hypoaspissensu lato by
The most recent taxonomic work on the genus was by
Samples were collected from bark of elm trees over a period of two years (2002–2004), in Isfahan Province. Mites were removed from the bark by extraction using Tullgren funnels. Mites were cleared in Nesbitt’s solution and mounted in Hoyer’s medium (Walter and Krantz 2009). The line drawings and examinations of the specimens were performed with an Olympus BX51 phase contrast microscope equipped with a drawing tube. All measurements in the descriptions are given in micrometres (µm). Dorsal shield length and width were taken from the anterior to posterior margins along the midline, and at its broadest point, respectively. Length and width of the sternal shield were measured from the anterior point to the posterior point at the full length and broadest point, respectively. Genito-ventral shield length and width were measured along the midline from the posterior margin of the sternal shield to the posterior margin of the genito-ventral shield, and at the maximum, respectively. Leg lengths were measured from base of the coxa to the apex of the tarsus, excluding the pre-tarsus. Lengths for the fixed and movable cheliceral digits were taken from the base of the digits to their tips. The nomenclature used for the dorsal idiosomal chaetotaxy is that of
Laelaspisella Marais & Loots, 1969: 1.
Laelaspisella epigynalis Marais & Loots, 1969, by original designation.
The presence of pre-sternal plates and an expanded epigynal shield suggests a superficial similarity to Gymnolaelaps. However, Laelaspisella has a hypertrichous dorsal shield, two ventral setae on genu IV, and lacks metasternal setae st4. Gymnolaelaps has a normal complement of 40 pairs of setae on the dorsal shield, one ventral seta on genu IV, and the metasternal setae are always present.
The genus is characterised by a well sclerotised hypertrichous holodorsal shield, (podonotal area hypertrichous or with normal chaetotaxy), convex dorsal shield and flat venter, and a large genito-ventral shield, expanded posterior to the genital setae, with strong reticulated ornamentation. Pre-sternal plates present (lightly sclerotised in the new species); female sternal shield deeply concave in posterior margin and lateral corners extended to the level of coxa III, with three pairs of simple sternal setae; endopodal shields between coxae II and III fused with sternal shield. Metasternal setae st4 always absent; pores iv3 present on the posterolateral extensions of sternal shield; exopodal plate behind coxa IV triangular, more or less contiguous with but separate from peritrematal shields; peritrematal shield extending posteriorly well past coxae IV; genito-ventral shield with rounded posterior margin separate from anal shield, or with straight posterior margin touching anal shield; opisthogastric membrane with eight to nine pairs of smooth setae (r6 is not included), setae Jv5 and Zv5 longer than other opisthogastric area setae or normal (not longer than the other dorsal setae); anterior margin of epistome smooth or with irregular minute denticulation; chelicera with small and robust digits with few teeth, dorsal seta sometimes absent. Hypostomal groove with four to six rows of denticles. Corniculi well-sclerotised; palp tarsal claw with two pointed tines. Legs shorter than idiosoma, genu IV with ten setae (2 2/1 3/1 1), genu I with seta pd3 absent (2 3/2 2/1 2) or present (2 3/2 3/1 2).
These characters are variable within the genus Laelaspisella: (1) dorsal seta of chelicera present or absent; (2) podonotal shield hypertrichous or with normal chaetotaxy; (3) setae Jv5 and Zv5 expanded or normal; (4) seta pd3 on genu I present or absent; (5) extra opisthogastric setae present or absent; (6) genito-ventral shield with rounded posterior margin separate from anal shield, or with straight posterior margin touching anal shield; (7) Anterior margin of epistome smooth or with irregular minute denticulation.
To separate Laelaspisella from Gymnolaelaps, the following characters can be used: Laelaspisella has (1) opisthonotal area of dorsal shield hypertrichous; (2) metasternal setae absent; (3) genu IV with two ventral setae; (4) pore iv3 on sternal shield. Gymnolaelaps has (1) opisthonotal area of dorsal shield not hypertrichous; (2) metasternal setae present; (3) genu IV with one ventral seta; (4) pore iv3 in soft skin.
Holotype, female, Iran, Isfahan, March-April 2002, A. Jalalizand coll., from bark of elm trees (in YIAU). Paratypes, five females same data as holotype (in YIAU, JAZM and
Dorsal idiosoma (Fig.
Ventral idiosoma (Fig.
Gnathosoma. Hypostomal groove with four rows of denticles each bearing 2–5 small teeth (Fig.
Legs. Legs II and III shorter (309-320, 302-310), I and IV longer (349-360, 431-447) (excluding pre-tarsus). Leg I: coxa 0 0/1 0/1 0, trochanter 1 0/2 1/1 1, femur 2 2/1 3/3 2, genu 2 3/2 3/1 2 (Fig.
Not seen, apparently unsclerotised.
It is with great pleasure that we name this species after Elsa Joharchi, the new-born daughter of the first author.
Laelaspisella elsae sp. n. differs from all other species in the genus in having the genito-ventral shield broad and bearing genital setae st5 and two additional pairs of setae on its surface, hypostomal groove with four rows of denticles, genu I with seta pd3 (2 3/2 3/1 2) and two ventral setae on genu IV (2 2/1 3/1 1), also dorsal seta of chelicera absent.
Pseudoparasitus (Gymnolaelaps) tonsilis Karg, 1989a: 335.
The paratype specimen of Karg’s collection was examined by the first author and this information is as follows: Slide
Pseudoparasitus (Gymnolaelaps) tonsilis shares all important character states with the genus Laelaspisella : dorsal shield hypertrichous, two ventral setae on genu IV (2 2/1 3/1 1), genu I (2 3/2 3/1 2) seta pd3 present, lacks metasternal setae st4, seta Jv5 long (
Laelaps (Eulaelaps) canestrinii
Laelaps (Hypoaspis) canestrinii
Gymnolaelaps canestrinii (Berlese, 1903) sensu Costa, 1962: 491.
The identity of L. canestrinii is very confused. In Laelaps canestrinii Berlese, 1892, the female has a very wide genito-ventral shield carrying four pairs of setae in addition to st5, and has a straight posterior margin. There are no setae between the genito-ventral and anal shields. The sternal shield has only two pairs of setae, the metasternal plates and setae are absent, the anal shield is wider than long, and the movable digit of the chelicera has three teeth. In the male the anal shield is fused to the genito-ventral shield, with the fusion marked by a distinct line.
All six species of Laelaspisella share four important diagnostic character states: (1) hypertrichous dorsal shield (in both the podonotal and opisthonotal region or only in the opisthonotal region); (2) two ventral setae on genu IV (2 2/1 3/1 1); (3) metasternal setae st4 absent but metasternal poroids present on the posterolateral extensions of sternal shield; (4) Palp tarsal claw with two pointed tines.
Some of the diagnostic characters of the Laelaspisella elsae were unique within the known Laelaspisella species (such as: presternal area with transverse lightly sclerotised presternal lines, genito-ventral bearing genital setae st5 and two additional pairs of setae on its surface and hypostomal groove with four rows of denticles each bearing 2-5 small teeth) but at the present time, creating a new monotypic genus to accommodate the new species would not help to clarify the taxonomic problems existing within the family Laelapidae. Therefore, this species is provisionally placed in Laelaspisella until a comprehensive revision of all these genera resolves its relationships.
The key below distinguishes the six species of Laelaspisella. In this key we recognise two distinct groups of species within the genus. All species group of epigynalis have 12 setae on genu I (2 3/2 2/1 2), with seta pd3 absent. Group elsae species have 13 setae on genu I (2 3/2 3/1 2), with seta pd3 present.
1 | Genu I with 12 setae (2 3/2 2/1 2) pd3 absent epigynalis species group | 2 |
– | Genu I with 13 setae (2 3/2 3/1 2) pd3 present elsae species group | 3 |
2 | Genito-ventral shield tapered posteriorly, opisthogastric area with eight pairs of setae | Laelaspisella macrodorsalis Marais & Loots, 1969 |
– | Genito-ventral shield rounded posteriorly, opisthogastric area with nine pairs of setae | L. epigynialis Marais & Loots, 1969 |
3 | Dorsal shield hypertrichous in both the podonotal and opisthonotal region | 4 |
– | Dorsal shield hypertrichous only in the opisthonotal region | 5 |
4 | Post-stigmatal section of peritrematal shield elongate, extending well behind exopodal shield | L. tonsilis (Karg, 1989a) |
– | Post-stigmatal section of peritrematal shield short and wide | Laelaspisella kabitae (Bhattacharyya, 1968) |
5. | Genito-ventral shield bearing genital setae st5 and two additional pairs of setae on its surface, dorsal shield with long setae | Laelaspisella elsae sp. n. |
– | Genito-ventral shield bearing only genital setae st5 on its surface, dorsal shield with short setae | Laelaspisella berlesei Joharchi, nom. n. |
We are deeply grateful to the Museum für Naturkunde Berlin (Dr. Jason A. Dunlop and Dr. Anja Friederichs) for support of the first author during his visit to museum. We gratefully acknowledge Dr. Bruce Halliday (