Maracarus gracilipes
Creators: name: Durucan, Furkan
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Trombidiformes
Halacaridae
Maracarus
Maracarus gracilipes

description: Maracarus gracilipes (Trouessart, 1889)
Figures. 9,10; Table 4
Halacarus (Copidognathus) gracilipes,—Trouessart 1894
Copidognathus (Copidognathopsis) gracilipes,—Viets 1927
Copidognathopsis gracilipes,—Viets 1928
Copidognathus (Arhodeoporus) gracilipes,—Newell 1947
Material examined. All specimens obtained from St. 1 (Muğla, Fethiye), medium coarse sand, 8 m depth, 36.60251°N 29.03095°E, 13 September 2019. Female, male, and deutonymph (FDHAL-24/37), female, dissected and mounted into one slide; Male (FDHAL-24/38), dissected and mounted into one slide; Deutonymph (FDHAL-24/39), undissected and mounted into one slide.
Description. Measurements presented in Table 4.
Morphology and notes. Female Dorsal plates (AD, OC and PD) with reticulate sculpturing (Fig. 9A). AD as long as wide.AD with three raised porose areolae. Anterior areolae 20 long, 17 wide. Each posterior areolae 32 long, 20 wide and with 19–20 polygons. Pair of glp-1 medial to pair of ds-1, ds-2 and ds-3 on membranous integument, the former between OC and AD, the later between AD and PD. OC posteriorly tail like, extending beyond level of leg IV insertions and with two corneae. Gland pores (glp-2) lateral to OC as shown in Fig 9A. OC with porose areola between gland pore and posterior cornea. Pore canaliculus immediately posterior to the porose areola and gland pore. PD wide, rounded anteriorly, with reticulate ornamentation as illustrated except for a pairs of narrow costae which carry porous areolae. Pair of ds-4 at 0.36 of the total length of PD, pair of ds-5 apical on cones at 0.71 of the total length of PD. Pair of ds-6 on anal cone (Fig. 9A).
Ventral plates (AE, PE, GA) reticulate porose areolae as illustrated (Fig. 9B). Posterior margin of AE and anterior margin of GA truncate. AE with 3 pairs of setae and pair of large epimeral pores (7). PE with 2 dorsal and 3 ventral setae. Porose areolae anterior to insertions of leg III, middle of plate and anterior to insertions of leg IV. Interval between anterior margin of GA and GO same as 2.2 times length of GO. Pair of longitudinal porose areolae (225 long) lateral to GO. GA with 6 pgs, genital sclerites with four sgs. GA widening posteriorly. Ovipositor (95) extending beyond anterior pair of pgs.
Dorsal gnathosoma reticulate (Fig. 9D), tectum truncate. Rostrum triangular, not extending beyond P-2. Rostral setae at tip of rostrum. Distal maxillary setae at about 0.44 level of rostrum, basal maxillary setae at about 0.91 level of rostrum. P1 14, P2 41, P3 10, P4 50 long. P4 with 3 long setae in basal whorl. Ventral gnathosomal base with pair of reticulate porose areolae, 42 long, 24 wide. Chelicera with claw and flap-like dorsal process (Fig. 9E).
All legs (Figs. 9F–I) slender and shorter than idiosoma. Leg I to leg IV lengths (without claws) 285, 215, 253, 246 respectively. Leg chaetotaxy from trochanter to tarsus (bipectinated setae between parentheses, parambulacral setae and solenidia excluded): leg I: 1, 2, 5, 4, 8, 6; leg II: 1, 2, 5, 4, 8(2), 4; leg III: 1, 2, 3, 3, 5(1), 4; leg IV: 0, 2, 3, 3, 5, 3. Tibiae I to IV with 0, 2, 1, 0 bipectinate setae. Tarsus I with 3 dorsal setae, 1 dorsolateral seta-like solenidion, 3 ventral setae and apically with pair of doubled pas. Tarsus II with 3 dorsal setae, a dorsomedial seta-like solenidion, 1 ventral setae, and pair of pas. Tarsi III and IV with 4 and 3 dorsal setae, respectively. Tibia I with four slender smooth ventral setae; tibia II with two sharply ending bipectinate ventromedial and two slender ventral setae. Ventromedial setae of tibia III bipectinate and blunt, ventrolateral setae long. Both ventral and ventrolateral setae of tibia IV smooth and long. All legs with two lateral claws with accessory process. Claw pecten with delicate tines and a small bidentate median claw.
Male. Male is similar to female except for the genital plate (Fig. 9C). GO surrounded by 26 perigenital setae. five pairs of subgenital setae are present. GO 42 long, 25 wide. Distance between edges of GA and GO 100, equalling 0.42 of GO length. Spermatopositor large 95 extending anterior margin of GO and porose areolae of GA.
Deutonymph. Dorsal and ventral plates and porose areolae on plates less developed than adults (Figs. 10A,B). OC not tail like and posteriorly extending to level of leg III insertions. Genitoanal plate is almost rectangular with four perigenital setae and two pairs of genital acetabula. Rostrum triangular, not extending beyond P-2. Rostral setae at tip of rostrum. Ventral gnathosomal base with pair of reticulate porose areolae. Tectum truncate (Fig. 10C). Leg chaetotaxy (Figs. 10D–G) from trochanter to tarsus (bipectinated setae between parentheses, parambulacral setae and solenidia excluded): leg I: 1, 2, 5, 4, 8, 5; leg II: 1, 2, 4, 4, 7(2), 3; leg III: 1, 2, 3, 3, 5(1), 4; leg IV: 0, 1, 3, 3, 5, 3. Tibia II and III with 2 and 1 bipectinate setae, respectively.
Remarks. Maracarus gracilipes was originally described from northeastern Atlantic Ocean (English Channel) by Trouessart (1889). After that, the species was reported from many localities in northeastern Atlantic Ocean and Mediterranean and Black Sea (Bartsch, 2016). The species M. gracilipes is reported from Türkiye for the first time in this study based on female, male and deutonymph. The morphological characteristics, sizes of adult and deutonymph specimens presented in this study fit well in the description by Bartsch (1977) and Bartsch (1998).
Key to species of the Maracarus gracilipes group
1. All dorsal and ventral plates with conspicuous reticulate ornamentation (Figures 3A–C); two pairs of costae; middle costae anteriorly almost joined to lateral costae; Corneae lacking (Figure 3F); rostrum extending beyond P2 (Figure 3K)..........
...................................................................................... M. terueae n. sp. 2. All dorsal plates with porous areolae, reticulate ornamentation; OC with two corneae; rostrum not extending beyond P2.... 3
3. AE with porose areolae................................................................................ 5 4. AE without porose areolae (Figure 2B)........................................................ M. almiri n. sp. 5. AE with one porose areolae and PE with two porose areolae............................... M. minor (Bartsch, 1977) 6. AE with two separate porose areolae or porose areolae combined on plate; PE with three porose areolae................ 7 7. Porose areolae on AE and PE with elaborate and anterior porose areolae on AE not anteriorly beyond to epimeral pores.... 9 8. Porose areolae on AE and PE much smaller and anterior porose areolae on AE anterior beyond to epimeral pores..........
................................................................................. M. subtilis (Otto, 2000) 9. Porose areolae on AE large (cover almost 1/2 of plate) (Figure 7B,C)................................ M. pedroi n. sp. 10. Porose areolae on AE small (do not cover 1/2 of plate)....................................................... 11 11. Male porose areolae on GA clearly divided into two parts; female porose areolae on GA oblong shape and extending beyond
GO and pgs-2 (Figure 9B,C)................................................... M. gracilipes (Trouessart, 1889) 12. Male porose areolae on GA not divided; female porose areolae on GA small and almost reach anterior to GO but not extending beyond pgs-2................................................................. M. perlucidus (Bartsch, 1983)
description: Published as part of Durucan, Furkan, 2024, The genus Maracarus (Acari: Halacaridae), description of three new species and one new record from Türkiye, pp. 539-556 in Zootaxa 5486 (4) on pages 552-556, DOI: 10.11646/zootaxa.5486.4.4, http://zenodo.org/record/13210228