Tarsonemini, Canestrini & Fanzago, 1877

Rezende, José Marcos, Bauchan, Gary, Lin, Jian-Zhen, Ochoa, Ronald & Lofego, Antonio Carlos, 2024, Review of the genus Daidalotarsonemus De Leon (Acari: Prostigmata: Tarsonemidae), Zootaxa 5426 (1), pp. 1-170 : 9-10

Tribe Tarsonemini Canestrini & Fanzago, 1877

Genus Daidalotarsonemus De Leon, 1956

Type species: Daidalotarsonemus tessellatus De Leon, 1956 ; by original designation. Type locality: South Miami , State of Florida, USA .

Description. With character states as described by Lindquist (1986), but restricted or augmented as follows:

Adults. Body. Medium-sized tarsonemids (idiosomal length 150–200 μm). Gnathosoma . Gnathosomal capsule usually longer than wide, with anterior extremity prolonged, slightly, or distinctly beak-like. Palpi short (1/4 length of gnathosoma) to moderately long (1/2 length of gnathosoma). Pharynx fusiform, occupying about 1/3 of gnathosomal width, thick, with muscular, thinly sclerotized walls. Dorsal and ventral gnathosomal setae smooth, unmodified. Palpcoxal setae not observed under LT-SEM. Cheliceral stylets short, with basal levers inconspicuous. Dorsal apodeme distinct on gnathosoma.

Females. Dorsum. Prodorsum, tergites C, D and EF usually reticulate medially and wrinkled laterally.Prodorsum broadly extended, hoodlike, over gnathosoma. Stigmata located equidistant to v1 and sc2 setal bases, opening on deep emarginations of lateral margins of prodorsum. Bothridial seta sc1 capitate, with tiny spines, at least partially covered by prodorsum. Prodorsum and tergite H usually with unmodified setae, smooth or slightly barbed. Setae of tergite C (c1 and c2) unmodified for most species, but also leaf-shaped or stout, capitate in some cases. Setae c1 transversely or obliquely aligned to c2, according to species. Setae of tergites D and EF (d, e and f) slightly barbed and usually leaf-shaped or stout, capitate. Venter. Setae 1a posteriad apodemes 1; 2a posterolaterad apodemes 2. Apodemes 1 forming a Y-shaped juncture with prosternal apodeme. Apodemes 2 not, weakly, or totally united with prosternal apodeme. Prosternal apodeme not, weakly, or fully united with sejugal apodeme. Sejugal apodeme continuous or weakened medially. Apodemes 3 extending diagonally from trochanters III to setae 3a, at level of anterior end of poststernal apodeme. Apodemes 4 connected to each other and to poststernal apodeme medially. Poststernal apodeme developed, generally bifurcated anteriorly. Two pairs of setae (3a and 3b) on metapodosomal venter. Fissures overlapping apodemes on metapodosoma, for some species. Tegula short, truncate, or slightly arched posteriorly. Pair of pseudanal setae present. Legs. Leg I chaetotaxy: 3-4-6(1 or 2 φ)+7(1 ω). Tibia I sensory cluster complete (φ1, φ2, famulus k), or lacking solenidion φ1. Tarsal solenidion ω stout, widest medially. Leg II chaetotaxy: 3-3-4-4 (1 ω). Genu II with seta l’ usually stout, barbed. Tarsal solenidion ω stout, widest medially. Leg III chaetotaxy: 1+2 or 3-4-4. Genual seta l” present or absent.

Males. Dorsum. Prodorsal shield trapezoidal. Setae sc2 usually shorter than sc1, inserted laterad of oblique longitudinal alignment with preceding three pairs (v1 v2 and sc1). Shield CD with setae arranged in rows (c2 transversely aligned anteriorly, c1 and d obliquely aligned posteriorly). Shield EF with paired setae f. Dorsal setae collectively moderately long and slightly barbed. Seta c1 closer to d than to c2, anterolateral to former. Venter. Apodemes 1 forming a Y-shaped juncture with prosternal apodeme.Apodemes 2 not united with prosternal apodeme. Sejugal apodeme continuous medially or interrupted on either side of midline or reduced laterally.Poststernal apodeme usually divided posteriorly into apodemes 5 along different extent of its length. Anterior margins of coxisternal plates III–IV flattened and concave. Legs. Leg I chaetotaxy: 3-4-6(1 or 2 φ)+8(1 ω). Tibia I sensory cluster complete (φ1, φ2, famulus k), or lacking solenidion φ1. Solenidion ω stout, widest medially. Leg II chaetotaxy: 3-3-4-4 (1 ω). Solenidion ω stout, widest medially. Leg III chaetotaxy: 1-2 or 3-4-3. Claw well developed.

Larvae. As described by Lindquist (1986).

Differential diagnosis. Females: According to Ochoa et al. (1995), Daidalotarsonemus , Ceratotarsonemus and Excelsotarsonemus are similar by the presence of some dorsal idiosomal setae heavily modified (either greatly elongated and barbed, or thickened and lanceolate to capitate), in lacking setae l” on femur I, pv” on tarsi II–III and spine-like seta pl” on tarsus II, and in possessing a prodorsum deeply emarginated on either side to accommodate the stigmata. Daidalotarsonemus and Excelsotarsonemus are different from Ceratotarsonemus by the presence of three to four setae on femorogenu III ( Ceratotarsonemus presents only two setae, v’ F and l’ G); and by the dorsal setae c2 being shorter than distance between their bases. Daidalotarsonemus is distinguished from these two genera by possessing dorsal setae v1 and c2 smooth or slightly serrate but not modified (leaflike or heavily elongate); by the setae v1 being shorter than, or as long as, the distance between their bases; and by tergite D being distinctly reticulate. Males: (the comparison is only between Daidalotarsonemus and Ceratotarsonemus as there are no males recorded for Excelsotarsonemus ): they are similar in having the anterior margins of coxisternal plates III–IV concave, with the anterolateral corners of plates III angulate; and in having an elongated femorogenu bearing seta v’ Fe on a proximal angular projection on leg IV; and in having scapular setae sc1 very long and coarsely barbed. Daidalotarsonemus differs from Ceratotarsonemus by the tibia IV being elongated, three to five times longer than the tarsus, while in Ceratotarsonemus it is two times longer.

List of species given in alphabetical order: