Anomalohalacarus

Diagnostic figures of generalised Anomalohalacarus, from Bartsch (2006).

Belongs within: Halacaridae.

Anomalohalacarus is a genus of slender-bodied marine interstitial mites. Species have been recorded from the North Atlantic, Indian and Pacific Oceans.

Characters (from Bartsch 2006): Idiosoma: Length 200–520 μm. Idiosoma very slender; width less than interval between epimera II and III. Dorsal and ventral plates small, delicate, lacking conspicuous ornamentation. Ocular plates absent or reduced to minute sclerites; corneae lacking. Posterior dorsal plate present; in adults of most species divided longitudinally. One pair of gland pores on anterior dorsal plate, 0–1 pairs of pores in striated integument, 1–2 pairs on posterior dorsal plate. Dorsum with 5–6 pairs of idiosomatic setae; ds-1, ds-2 and ds-4 generally remarkably long; small adanal setae on anal cone. Anterior epimeral plate divided longitudinally in the majority of species (rarely epimera fused in the median); each plate with 3 ventral setae and pair of epimeral pores. Posterior epimeral plate small, with 1 dorsal and 2–3 ventral setae. Female genital plate divided; 2 pairs of perigenital setae on genital plates and 1 pair within striated integument, on a pair of small sclerites or on single median sclerite; genital groove present. Male genitoanal plate large; 7–50 pairs of perigenital setae lateral to genital opening and genital groove; genital sclerites with 3 pairs of subgenital setae. Gnathosoma: Longer than wide. Rostrum slender, parallel-sided; from half as long to almost as long as palps. Both pairs of maxillary setae inserted on rostrum. Four-segmented palps slender, attached laterally and surpassing rostrum. Second palpal segment with 1–2 setae, either a single basal seta or 1 basal and 1 distal seta. Third palpal segment short, with 1 spine. Fourth palpal segment with 3 setae in basal whorl; apically with setula and 2 spurs. Legs: All legs slender; anterior 2 pairs of legs widely separated from posterior ones. Leg I longer than leg II. Genu of leg I only slightly shorter than telofemur and tibia; genua II–IV shorter than adjoining leg segments. Dorsal and lateral setae on legs remarkably long. Basifemora I to IV with (1–)2,(1–)2(–3),1–2,0 setae, respectively. Tibia I ventrally with 0–2 short spurs, 0–2 delicately pectinated setae and 3–5 smooth setae; tibiae II–IV with 2–3,2–3,2 ventral setae, 1–3 of these setae bipectinate. Tarsus I with enlarged lateral fossa membrane, 3 dorsal setae, and solenidion adjacent to fossa membrane; ventrally with 1 spur, rarely 2 spurs, and pair of small, eupathid setae. Tarsus II with 3 dorsal setae, claviform dorsolateral solenidion, and 0–1 ventral setae. Tarsi III and IV each with 3 dorsal and 0 ventral setae. All tarsi with apical pair of parambulacral setae. Paired claws on tarsus I somewhat smaller than those on following tarsi. All tarsi with small median claw.

<==Anomalohalacarus Newell 1949 B86
    |--A. anomalus (Trouessart 1894) B86
    |--A. arenarius Bartsch 1978 B86
    |--A. intermedius Bartsch 1976 B86
    |--A. litoralis Bartsch 1981 B86
    |--A. marcandrei (Monniot 1967) B86
    |--A. minutus Bartsch 1976 B86
    |--A. ruffoi Morselli & Mari 1979 B86
    |--A. similis Bartsch 1976 B86
    |--A. tenellus Bartsch 1979 B86
    `--A. tenuis Bartsch 1979 B86

*Type species of generic name indicated

REFERENCES

[B86] Bartsch, I. 1986. Acari: Halacaridae. In Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna inhabiting Subterranean Waters (including the Marine Interstitial) (L. Botosaneanu, ed.) pp. 638-642. E. J. Brill / Dr. W. Backhuys: Leiden.

Bartsch, I. 2006. Halacaroidea (Acari): a guide to marine genera. Organisms Diversity and Evolution 6 (Electronic Suppl. 6): 1-104.