Mirabilithrombium Gabryś, 1999

Sevsay, Sevgi & Adil, Sezai, 2015, First larval description of the genus Mirabilithrombium Gabryś, 1999 (Acari, Microtrombidiidae) from Turkey, Turkish Journal of Zoology 39 (2), pp. 285-294 : 285-290

publication ID	https://doi.org/ 10.3906/zoo-1401-25
persistent identifier	https://treatment.plazi.org/id/916187D2-FF93-FFC0-1EAC-79B8EABFE179
treatment provided by	Felipe
scientific name	Mirabilithrombium Gabryś, 1999
status

Treatment

Genus Mirabilithrombium Gabryś, 1999

Type species Georgia mirabilis Willmann, 1950 Mirabilithrombium Gabryś, 1999

Diagnosis.

Adult. Medial face of palp tibia with strong paradont, 1 or 2 ctenidia, and a radula. Radula consists of a few spine-like setae. Lateral face of palp tibia with 1 or 2 long, solid basidonts. Crista metopica with anterior and posterior process; in posterior half, a sensillary area bearing 1 pair of filiform sensillary setae. Accessory posterior process present. Double eyes with large lenses situated on short stalks placed at sides of crista metopica at the level of midpoint of anterior process. Dorsal opisthosomal setae of 2 types, both covered with setules distributed along the stem. Setae of type I (pDS I) more robust, gradually longer and thicker towards idiosoma termination, distal part of the stem slightly bent to idiosoma and bearing 2–5 short lobes at the top. Setae of type II (pDS II) smaller, with slightly thickened, apically narrowing stem. Legs without lamellae, shorter than idiosoma. Tarsus I dilated, longer than high.

Larva. Gnathosoma with stephanostome, internal horseshoe-like sclerite distinct, but without lateral teeth. Palps with minute spine-like setae on femur and genu. Tritorostral setae (bs, hypostomalae) distally with finger-like projections. Cheliceral blade short and slightly curved. Lateral sclerite with 1 pair of adoral setae. Dorsum of idiosoma with scutum and scutellum. Scutum bent anterolaterally to the venter (stolascutum). Scutum bearing 3 pairs of nonspecialized setae and 1 pair of trichobothria. Scutellum with 1 pair c 1 setae. Dorsal setae barbed, arranged in rows, and situated on plates or platelets. Plates of c 2 and d 1 distinctly enlarged. Coxal setation formula: 2–1–1; all setae with at least 1 setula. All tarsi terminated with paired claws and empodium. Inner claw at tarsus III reduced to a spine. Scopa and lophotrix absent.

Distribution. Austria, Portugal, Spain, Tunisia, Turkey.

Mirabilithrombium turcicum sp. nov.

Adult female.

Standard measurements are given in Table 1. Body is red-colored in life. Idiosoma broadened at shoulders, narrowing posterior ( Figure 1A). Body length 1382–1614; width 985–1160.

SAL 55

SAW 111

SB 29

SE 135

pPr 111

acpPr 15

OL 86

OCM 117

ao 35

pO 30

O-O 248

OaD 113

OSD 103

GOP (L) 193

gs [S] min. not visible gs [S] max. 24

pgs [S] min. not visible pgs [S] max. not visible An (L) 60

An La min. 20

An La max. 24

Cx_I 164

Tr_I 105

Bf_I 222

Tf_I 164

Ge_I 172

Ti_I 193

Ta_I (L) 291

Ta_I (W) 158

Ta_I (L/W) 1.84

Leg I 1311 Cx_II 191

Tr_II 97

Bf_II 120

Tf_II 93

Ge_II 103

Ti_II 126

Ta_II 209

Leg II 939 Cx_III 139

Tr_III 84

Bf_III 136

Tf_III 87

Ge_III 98

Ti_III 126 Ta_III 196

Leg III 866 Cx_IV 185 Tr_IV 121

Bf_IV 181

Tf_IV 130 Ge_IV 153 Ti_IV 188 Ta_IV 242

110

not visible 83

114

246

111

184

not visible not visible not visible not visible not visible not visible not visible 147

175

143

155

176

255

137

1.86

1145

162

125

178

835

145

118

167

748

127

130

174

116

SEVSAY and ADİL / Turk J Zool

100 µm 100 µm 100 µm 100 µm

Gnathosoma. Palps strong ( Figure 1B). Lateral face of palp tibia ( Figure 1C) covered with numerous setulose setae, whip-like seta placed terminally near odontus; at the base of palp tarsus 2 long basidonts, distal ones usually the strongest and the longest. Medial face of palp tibia ( Figure 1D) with 2 often overlapping ctenidia and radulae; distal ctenidium composed of 4–5 spinisetae situated behind paradont; proximal ctenidium composed of 6–7 uniform spinisetae; radula consists of 5–6 long and very strong spine-like setae. Palp tarsus characteristic, long and cylindrical, with numerous feather-like setae ( Figure 1D) and with 3 eupathidia (ζ) distally and 1 solenidion (ω) laterally. Chelicerae typical for the family ( Figure 1E).

Idiosoma. Aspidosoma ( Figure 2A) triangular in outline. Anterior part of crista metopica relatively broad, almost-sclerotized vertex bears 9–10 long, setulose nonsensillary setae ( AM); rounded sensillary area bears 2 short, smooth sensillary setae; posterior process relatively short according to anterior process; accessory posterior process present. Two pair of eyes with large lenses on short stalks placed half-length on each side of anterior part of crista metopica; anterior lenses distinctly larger than posterior ones. Dorsal opisthosomal setae of 2 types ( Figure 2B). Setae of type I (pDS I) more robust, clearly longer, and distal part of the stem slightly bent to idiosoma bearing 2–5 short lobes at the top. Setae of type II (pDS II) smaller, with thinner, apically narrowing stem, and covered with setulae but only on 1/2 to 2/3 their length from base. Ventral setae of 1 type, similar to type II of dorsal ones and comparable in length. Three pairs of genital acetabula. External genitalia ( Figure 2C) consist of a pair of epivalves and centrovalves covered densely with setae; epivalval setae setulose, centrovalval setae smooth. Anus covered with setulose setae ( Figure 2D) .

100 µm 250 µm 100 µm 100 µm

Legs. Legs without lamellae, much shorter than idiosoma; tarsus I at least 1.8× longer than wide ( Figure 2E).

Deutonymph and male. Unknown.

Larvae.

Morphometric data are given in Table 2. Color in life is reddish.

Gnathosoma ( Figure 3A). Movable gnathosoma with stephanostome composed of distinct internal horseshoe-like sclerite without lateral teeth and inserted between outer and inner cuticular sheaths. Ventrally a pair of thick subcapitular setae (bs) with 6–7 finger-like digitations. Chelicera (45–50) typical ( Figure 3B), cheliceral blade fine, slightly curved, with 1 tiny hook at distal part of its internal edge. One pair of spine-like adoral setae (cs). Pedipalp formula: 0–N–N–NNN–NNNNNNNωζ. Palp femur and genu each with 1 minute, spine-like seta placed dorsally. Palp tibia ( Figure 3C) with 1 long and 1 shorter smooth seta and with 1 spine-like seta. Odontus divided almost its entire length. Palp tarsus ( Figure 3D) with 2 long and 4–5 shorter spine-like setae, 1 solenidion, and 1 eupathidium.

Idiosoma dorsum ( Figure 4A View Figure 4 ). Scutum and scutellum punctuations on the whole surface and striation. Scutum triangular in outline, rounded anteriorly, with almost straight posterior edge, and bent anterolaterally to the venter (stolascutum). Scutum striate longitudinally after AM setae and slightly rounded anteriorly; lateral borders concave near S and convex in line with PL bases. Setae AM smooth, setae AL and PL thinner and serrate. Sensillary setae covered with distinct setulae in distal part of stem. Paired eyes located on oval sclerites at the level of posterior part of scutum. Scutellum punctuate and with little striation, bears 1 pair of barbed c 1 setae situated ca. at half length of the sclerite. Dorsal setae barbed, arranged in rows and situated on plates or platelets. Plates of c 2 and d 1 distinctly enlarged. ƒD formula = (2)4–6–6–6–4 (setae d 1 on the largest plates, setae c 2 on the second largest plates, setae c 3 –d 3 on small platelets, setae e 1–3 and f 1–3 on smaller platelets). H row h 1 –h 2. Plates of setae h 1 united. Setae h 2 of comparable length (52–58) with other dorsal setae (23–53) and placed on tubercle-like protrusions.

Idiosoma ventrum ( Figure 4B View Figure 4 ). Cuticle smooth, folded in lines. Claparede’s organs placed laterally between coxae I and II. Coxa I with a long and setulose bifurcate seta 1a (15–17) and seta 1b (15–22). Supracoxala I absent. Coxa II with bifurcate seta 2b (19–21). Coxa III directed posterolaterally, with seta 3b with 3 long setules (16–18). Seta 3a (14–17) located outside coxa III, with 3–4 setules. Anal opening not sclerotized, located posterior to coxae III. Two pairs of setulose pseudanal setae (ps) placed anterolaterally to anal pore. Setae h 2 distinctly longer (37–44) than other ventral setae (23–41) and placed on tubercle-like protrusions.

Leg segmentation formula: 6–6–6. Leg setal formula: Leg I: Tr–1n; Fe–6n; Ge–4n, 2σ; Ti–6n, 2φ, 1Κ; Ta–15n, 2ζ, 1ω, 1ε ( Figure 5A View Figure 5 ). Leg II: Tr–1n; Fe–4n; Ge–2n, 1σ, 1Κ; Ti–5n, 2φ; Ta–13n, 1ζ, 1ω, 1ε ( Figure 5B View Figure 5 ). Leg III: Tr–1n; Fe–4n; Ge–2n, 1σ; Ti–5n; Ta–11n ( Figure 5C View Figure 5 ). All normal setae on legs covered with barbs. Pretarsi I–II with paired claws and claw-like empodium. Outer claw of tarsus III prominent, with splinters, inner claw reduced to a spine and empodium normal.

Key to the species of Mirabilithrombium (adults)

1. Distal end of pDS I bears 3 short lobes and pDS II covered with setules distributed along the stem………

……................................... Mirabilithrombium sibilatrix - Distal end of pDS I bears 2–5 short lobes and pDS II covered with setules but only on ½ to 2 / 3 their length from base.......................................................................... 2 2. pDS I <50 and tarsus I length/tarsus I height>2.6... ......

........................................... Mirabilithrombium mirabilis - pDS I>70 and tarsus I length/tarsus I height>1.8 .........

............................ Mirabilithrombium turcicum sp. nov.

Etymology. The specific epithet ‘ turcicum ’ refers to the type locality of this species, Turkey.

Type material. Holotype female collected on Ergan Mountain , Erzincan Province, Turkey (39°38′16″N, 39°31′31″E, 1328 m, 06.11.2012, leg. S. Adil). One paratype: same data as for holotype but collected 21.11.2011. Six larvae obtained from holotype females by experimental rearing. The type material and other specimens were deposited in the collection of the Biology Department, Erzincan University, Erzincan, Turkey. GoogleMaps

Distribution. Turkey.

Biology. The sampling area is characterized by forest and grass. A female, after being collected in the field (21 November 2011), laid eggs on the 22nd day of being kept under laboratory conditions; no larvae were obtained because the eggs were contaminated with mold. Another female (holotype) collected from the same field at a different time (6 November 2012) laid eggs on the 18th day of being kept under laboratory conditions (24 November). The eggs were spherical and clustered in 1 package. Although the eggs were also moldy, 10 days later (4 December) they turned into prelarvae; 6 larvae were obtained and transferred to alcohol (25 December).