A review of Cunaxidae (Acariformes, Trombidiformes): Histories and diagnoses of subfamilies and genera, keys to world species, and some new locality records

Abstract

Cunaxidae are predaceous mites found in a variety of habitats. This work provides comprehensive keys to world subfamilies, genera, and species. Diagnoses and historical reviews are provided for subfamilies and genera. Cunaxa boneti, C. denmarki, C. exoterica, C. floridanus, C. lehmanae, C. lukoschusi, C. metzi, C. myabunderensis, C newyorkensis, C. rackae, C. reevesi, and C. reticulatus are moved to Rubroscirus and C. otiosus, C. valentis, and C. rasile are returned to Rubroscirus. Cunaxoides neopectinatus is moved to Pulaeus. Neocunaxoides pradhani and N. gilbertoi are transferred to Scutopalus. Pulaeus minutus and P. subterraneus are moved to Lupaeus. Pseudobonzia bakari, P. malookensis, and P. shamshadi are transferred to Neobonzia. Dactyloscirus bifidus is transferred to Armascirus. Scirula papillata is reported from the Western Hemisphere for the first time. Armascirus ozarkensis, A. primigenius, and Dactyloscirus dolichosetosus are reported from new localities.

Keywords: Bdelloidea; Eupodina; Identification; Prostigmata; key.

Figure 1.

Examples of cunaxids in ethanol illustrating how they would appear while sorting. 1a Armascirus 1b Cunaxa 1c Pulaeus 1d Parabonzia 1e Coleoscirus 1f Neobonzia.

Figure 2.

Setal types. Relative sizes will vary within a given setal type 2a Attenuate solenidion (asl) 2b Blunt rod-like solenidion (bsl) 2c Elongate, tri-pronged famulus (fam), as seen in Dactyloscirus 2d Famulus (fam), as seen in the majority of cunaxids 2e Duplex setae - microseta (mst) and attenuate solenidion 2f Spine-like seta (spls) 2g Simple tactile seta (sts) 2h Trichobothrium (T).

Figures 3–6.

a. dorsal. b. ventral. 3 3-segmented pedipalp (Cunaxoidinae) 4 4-segmented pedipalp (Scirulinae) 5 5-segmented pedipalp that does not extend beyond the subcapitulum by more than the distal half of the genua (Bonziinae, Coleoscirinae, and Orangescirulinae) 6 5-segmented pedipalp that reaches beyond the subcapitulum by at least the distal half of the genua (Cunaxinae).

Figure 7.

Generalized schematic of cunaxid idiosomal morphology. 7a Dorsal. 7b Ventral.

Figure 8.

Bonziinae key illustrations. 8a Telofemoral branched seta present in Bonziinae 8b Bonzia 8c Parabonzia.

Figures 9–11.

Bonzia key illustrations. 9a Setose tibial trichobothrium 9b Smooth tibial trichobothrium 10a Spiculate dorsal setae 10b Smooth dorsal setae 11a Close up of a spiculate seta 11b Close up of a smooth seta.

Figures 12–14.

Parabonzia key illustrations. 12a Unbranched pedipalp telofemoral seta 12b Multi-branched pedipalp telofemoral seta 13 Lightly barbed pedipalp tibiotarsal sigmoid seta 14 Spur-like process on femora III.

Figures 15–17.

Cunaxoidinae key illustrations. Setae are removed from figures 16–17 for clarity 15a Idiosoma with poorly demarcated dorsal plates 15b Idiosoma with well demarcated dorsal plates 16a Pedipalp tibiotarsus with subapical process and small teeth present 16b Pedipalp tibiotarsus with subapical process and small teeth absent 17a Pedipalp tibiotarsus with a single pointed process 17b Pedipalp tibiotarsus with two pointed processes.

Figures 18–23.

Cunaxoides key illustrations. See key for explanations.

Figures 24–27.

Lupaeus illustrations. 24a Pedipalp tibiotarsus 24b Genital setae not in a row, g₃ out of line 25–27 Lupaeus key illustrations. Setae and cupules removed from figures 25a, b to increase clairity 25a Lupaeus longisetus, dorsal 25b Lupaeus polilloensis, dorsal 26a Ventral, small platelet present 26b Ventral, small platelet absent 27a Setae f₁, f₂ born on small platelets 27b Setae f₁, f₂ born on integument.

Figures 28–34.

Neocunaxoides key illustrations. See key for explanations of figures.

Figures 35–39.

Pulaeus illustrations. 35 Genital setae in a row 36–39 Pulaeus key illustrations 36, 37 Venter, setae removed for clairity 36a Coxae I–II not coalesced medially, median platelet present 36b Coxae I–II not coalesced medially, median platelet absent 37a Coxae I–II coalesced medially, median platelet present 37b Coxae I–II coalesced medially, median platelet absent 38a Dorsal shield with punctures 38b Dorsal shield with broken striae 39a–c Pedipalp tibiotarsus 39a Tibiotarsus with elongate apophysis 39b Tibiotarsus with flat apophysis 39c Tibiotarsus with flange-like apophysis.

Figures 40–44.

Scutopalus key illustrations. 40a Coxae I–II faintly divided 40b Coxae I–II totally divided 41 Coxae I–II fused medially 42 Dorsal shield with thick, rod-like setae present 43 Dorsal shield smooth or punctate 44a Dorsal shield rugose 44b Dorsal shield reticulate 44c Dorsal shield sparsely granulate 45a Setae mps, c₁, c₂, d₁, e₁, f₁ clavate 45b Setae mps, c₁, c₂, d₁, e₁, f₁ setiform 46 Setae lps, mps, c₁, c₂, d₁, e₁, f₁ set on tubercles.

Figures 45.

Scirula key illustrations. 45a Scirula impressa 45b Scirula papillata.

Figures 46–48.

Cunaxinae key illustrations. 46 Pedipalps, dorsal 46a Rubroscirus 46b Riscus 46c Allocunaxa 46d Cunaxatricha 46e Cunaxa 46f Armascirus 46g Dactyloscirus. 47a, b. Distal end of tarsus 47a Armascirini, showing large tarsal lobes 47b Cunaxini, showing small to medium tarsal lobes 48a–c Idiosoma, dorsal. Setae and cupules have been removed for clairity. Shape of proterosomal plate and presence or absence, shape, and extent of hysterosomal plate(s) will differ between species 48a Plates smooth 48b Plates with dot-like pattern 48c Plates with reticulated pattern.

Figures 49–53.

Armascirus key illustrations. 49–51 Dorsal idiosoma 49a–e Hysterosomal shield complemented with setae 50a–d Hysterosomal shield small, not complemented with setae 51a–c Hysterosomal shield absent 52a, b Pedipalp tibiotarsal claw 52a Single claw 52b Bifid claw 53a Hysterosomal plate concave on lateral edges 53b Hysterosomal plate not concave on lateral edges.

Figures 54, 55.

Cunaxa key illustrations. 54a–e Proterosomal shield, dorsal 54a Proterosomal shield with oval area formed by broken striae around pt present, mps present 54b Proterosomal shield with oval area formed by broken striae around pt absent, mps present 54c Proterosomal shield striated, mps present 54d Proterosomal shield smooth, mps present 54e Proterosomal shield with lps absent 55a Smooth f₁, h₁ 55b Spiculate f₁, h₁.

Figures 56–60.

Cunaxa key illustrations. 56a, b Integumental striations 57a Chelicera with longitudinal striations present 57a Chelicera with longitudinal striations absent 58a–f Examples of variation in the hysterosomal median plate 59a Pedipalp telofemoral apophysis uncinated 59b Pedipalp telofemoral apophysis truncated 59c Pedipalp telofemoral apophysis short and cone-like 59d Pedipalp telofemoral apophysis short and finger-like 59e Pedipalp telofemoral femoral apophysis long 60a Pedipalp tibiotarsus with small teeth present 60b Pedipalp tibiotarsus with small teeth absent.

Figures 61–62.

Dactyloscirus key illustrations. 61a–h Pedipalp genu and tibiotarsus with adjoining apophysis present 61i Close up of bifid claw 62a–d Pedipalp genu and tibiotarsus with adjoining apophysis absent 62e Close up of trifid claw.

Figures 63–65.

Dactyloscirus key illustrations. 63a–d Dorsal idiosoma, lateral hysterosomal platelets present 64a–f Dorsal idiosoma, lateral hysterosomal platelet absent 65a Pedipalp telofemur with one apophysis, which is about as long as the width of the telofemur 65b Pedipalp telofemur with one apophysis, which is shorter than the width of the telofemur 65c, d Pedipalp telofemur with two apophyses, one apical and one basal which is flattened and disc-shaped.

Figures 66–69.

Cunaxoidinae key illustrations. 66a–d Idiosoma, dorsal. Position of setae will vary between species. 67a–d Idiosoma, ventral 66a, 67a Generalized Scutascirus. Presence, position, and extent of lateral plates will vary between species 66b, 67b Generalized Coleoscirus 66c, 67c Generalized Pseudobonzia 66d, 67d Generalized Neobonzia 68a Scutascirus pedipalp tibiotarsus, arrow indicates bifurcate tubercle 68b Coleoscirus pedipalp tibiotarsus, arrow indicates plan tubercle 69a Neoscirula pedipalps with short, cone-like tibiotarsus 69b Pseudobonzia and Neobonzia pedipalps with elongate, s-shaped tibiotarsus.

Figures 70–74.

Coleoscirus key illustrations. 70 Dorsal idiosomal shield with horizontal reticulations present 71 Gnathosoma with extensive reticulations present 72a Sternal plate rounded posteriomedially, indentation absent 72b Sternal plate rounded posteriomedially, indentation present 72c Sternal plate truncated posteriomedially 73a Dorsal idiosomal shield even sclerotized, light reticulation present 73b Dorsal idiosomal shield unevenly sclerotized, light reticulation absent 74a Integumental dots on legs forming rows 74b Integumental dots on legs random.

Figures 75, 76.

Neobonzia key illustrations 75a Sensilla at and pt clavate, short, length less than the width of the proterosomal shield 75b Sensilla at and pt clavate, long, length greater than the width of the proterosomal shield 75c Sensilla at and pt normal, not clavate 76a Coxae I–II nearly touching medially 76b Coxae I–II widely separated medially.

Figures 77–87.

Neoscirula key illustrations 77a Pedipalp basifemoral dorsal seta spine-like 77b Pedipalp basifemoral dorsal seta simple 78a Proterosomal shield with polygonal subcuticular sculpturing present 78b Proterosomal shield with polygonal subcuticular sculpturing absent 79a Sternal shield v-shaped posteriomedially, with polygonal subcuticular sculpturing absent 79b Sternal shield rounded posteriomedially, with polygonal subcuticular sculpturing present 80a Chelicera with dorsomedial reticulations present 80b Chelicera with dorsomedial reticulations absent 81a Pedipalp genua with hook-like apophysis present 81b Pedipalp genua with hook-like apophysis absent 82a Pedipalp tibiotarsal claw with tooth present 82b Pedipalp tibiotarsal claw with tooth absent 83a Pedipalp tibiotarsus with tubercle present 83b Pedipalp tibiotarsus with tubercle absent 84a Hypognathum with ventroapical shield-like process present 84b Hypognathum with ventroapical shield-like process absent 85a Chelicera tapering gradually 85b Chelicera tapering suddenly 86a Proterosomal shield with polygonal subcuticular sculpturing present 86b Proterosomal shield with polygonal subcuticular sculpturing absent 87a Subcapitulum with row of basal subcuticular sculpturing present 87b Subcapitulum with row of basal subcuticular sculpturing absent.

Figures 88, 89.

Pseudobonzia key illustrations 88a Pedipalp basifemur and telofemur with spine-like setae on both segments 88b Pedipalp basifemur and telofemur with simple setae on both segments 88c Pedipalp with simple seta on basifemur, spine-like seta on telofemur 89a Proterosomal plate convex posteriomedially 89b Proterosomal plate not convex posteriomedially.

Figures 90, 91.

Scutascirus key illustrations. 90a (after Corpuz-Raros and Garcia 1996). Pedipalp with tubercle not branched 90b (after Den Heyer 1980b). Pedipalp tibiotarsus with bifurcate tubercle positioned halfway along the length of the segment 90c (after Den Heyer 1980b). Pedipalp tibiotarsus with bifurcate tubercle positioned on distal third of segment 90d (after Lin et al. 2001). Pedipalp tibiotarsus with trifurcate tubercle 90a (after Den Heyer 1980b). Four pairs of dorsolateral hysterosomal plates present 91b (after Corpuz-Raros and Garcia 1996). Five pairs of dorsolateral hysterosomal plates present.