Ulyxes, Shaw, 2014

Shaw, Matthew D., 2014, Ulyxes, a new Australopapuan mite genus associated with arboreal nests (Acari: Laelapidae), Zootaxa 3878 (3), pp. 261-290 : 263-266

Ulyxes gen. nov.

( Figs 1−59 )

Type species: Haemolaelaps ulysses Domrow, 1961: 63 .

Diagnosis. Female. Medium-sized to large mesostigmatan mites.

Dorsum. Mid-podonotal region of dorsal shield smooth, or almost so. Lateral margins and opisthonotal region of dorsal shield usually with reticulations. Many species with 39 paired dorsal setae as defined for holotrichous Laelapidae by Evans & Till (1965). Some species exhibit loss of podonotal z3 and px2–3, and U. sisyphus exhibits further hypotrichy as noted in the key. Dorsal setae smooth, except U. laertes has Z5 with a few incipient barbs. Dorsal setae sometimes reduced to microsetae ( U. calypso and U. telemachus ). Anterior hexagon of podonotum lacks accessory setae. Accessory Jx setae absent in U. calypso , U. sisyphus and U. telemachus . Other species have 2–8 accessory Jx setae, which are borne in a posteriorly-positioned field in vicinity of J4, some may appear paired, none anteriad level of mid J3–J4.

Gnathosoma . Lateral arms of internal malae have fimbriae bearing highly charactertistic expanded tips (except in U. laertes , U. telemachus and U. theoclymenus ). These modified fimbriae are distally inflated, up to 2µm wide, and may be densely clustered. Pilus dentilis short and uninflated. Cheliceral digits show great variation in size and dentition ( Table 3 ). Fixed digit dentition varying in number and development from edentate to four strong teeth (count excludes apically-divided tip). Subcheliceral shelf usually with trident apex, but with three exceptions: U. calypso with 4−6 tines, U. species B with four tines, U. laertes with two tines and U. euryclea has an undivided pointed tip. Inner palp trochanteral setae, either setiform or blade-like (2–13 wide). Deutosternal groove with six rows of denticles; maximum number of denticles per row varies greatly, 2–19.

Venter. Tritosternal base smooth. Genito-ventral shield bearing st5, sometimes Zv1 and rarely also Jv1. Genitoventral shield extensive reaching close to, or touching, anal shield. Anterior portion of shield narrowly bordered by longitudinal striae extending posteriorly only to level of Jv1 or less. Shield bearing 6–8 serially-regular, broadly transverse striae (except with obscure striae in U. ulixes , apparently smooth in unnamed species A and with reticulate striae in U. sisyphus ). Anal shield broad being at least as broad as long or very broad (e. g. ca 1. 6 times broader in U. penelope ). Opisthogaster mildly to strongly hypertrichous, or hypotrichous in U. sisyphus .

Legs. Ulyxes spp are readily distinguished by certain dorsal leg setae being apically bifid on trochantera and femora ( Figs 9 , 18 , 41 ). Apically bifid setae may be short or long, stout or slender, and have parallel, non-tapering sides. They are flattened (strap-like). They are never borne ventrally (with one possible exception, see Fig. 42 ).These differ in both number and position between species, providing setal signatures that are largely characteristic of, and consistent within, a species. There are 12 different setal positions known to bear apically bifid setae of which 5–10 are bifid on any one species ( Table 4 ). Barbed setae absent. Tarsus I with apical stalk short, at most 16 long, or absent. Leg chaetotaxy holotrichous as defined by Evans (1963) for Laelapidae except genu IV variable with 8–10 setae, and U. sisyphus hypotrichous on various other segments ( Domrow, 1981).

Male. The six known males are the previously described U. telemachus , U. ulixes and U. sisyphus ( Domrow, 1964, 1972a, 1981); and described here are males of U. euryclea , U. laertes (Domrow) and U. penelope (Domrow) .

Cheliceral digits variable. Fixed digit varies from not reduced at all in U. laertes ( Fig. 57 ) or U. euryclea ( Fig. 56 ) to strongly reduced in U. telemachus ( Fig. 52 ). All species have fixed digits with apical hooks except U. telemachus . In all species the pilus dentilis emerges from the distal half, including at the apex in U. telemachus . Spermatodactyl varies from being mostly free of movable digit from ca. 10% of length fused, to 80% of length fused. The spermatodactyl is moderately long at most and upturns abruptly with a distinct bend. Spermatodactyl tip usually blunt and rounded but sometimes with a small triangular projection providing a sharp-tip ( U. euryclea , Fig. 24 ). Genital opening wider than deep, set anteriorly with posterior edge at least level with st1 ( Figs 26 , 40 , 46 ). Posterior holoventral shield with circumanal setae plus five setal pairs, or only four pairs with Jv3 off shield ( U. euryclea , U. ulixes ) or just three pairs with Jv3 and Zv2 off shield ( U. penelope , U. telemachus ). Tarsus II av2 distinctly modified in U. penelope ( Fig. 42 ).

Etymology. Ulyxes is a variant spelling of Ulysses.

Remarks. Ulyxes spp comprises thirteen species, eight previously described and five undescribed: U. telemachus on two small congeneric dasyurid marsupials ( Domrow, 1964); U. laertes from an Australian endemic murid rodent ( Domrow, 1972a); U. euryclea from the cavity nests of cockatoos and Leadbeater’s possum described herein; U. theoclymenus from a Papuan lory here described, and the remaining ten species on an diverse array of possums in the superfamilies Petauroidea ( Acrobatidae , Petauridae , Pseudocheiriidae) and Phalangeroidea ( Domrow, 1961, 1964, 1981). Host and area relationships of Ulyxes spp , described and undescribed, are given in Table 2 .

Haemolaelaps was resurrected from synonomy and rediagnosed in a separate paper ( Shaw 2014), where it is redefined as equivalent to the Haemolaelaps marsupialis group ( Domrow, 1988) and herein referred to as Haemolaelaps sensu stricto. Here I briefly contrast the diagnoses of Haemolaelaps ss and its former congener Ulyxes . The following five characters apply to Haemolaelaps sensu stricto, but not Ulyxes : there are never unpaired dorsal setae, the pilus dentilis is long, being at least as long as the movable digit (except shorter in H. hattenae ), the fimbriae on the lateral arms of internal malae never have inflated tips, the second poststigmatal pore is enlarged, leg setae are always barbed. Also the pilus dentilis of the male always emerges from the apex of the fixed digit in Haemolaelaps ss. Haemolaelaps is one of seven described Australian genera that are related to Ulyxes , and I regard Ulyxes as more closely related to some of these (e. g. Nidilaelaps ) than it is to Haemolaelaps ss.

Key to female Ulyxes spp

1. Fixed digit with 0–1 teeth, not including divided apex........................................................ 2

- Fixed digit with 2–4 teeth, not including divided apex....................................................... 8

2. Sternal setae 1–3 elongate and strongly thickened, ca. 10 µm or more at base ( Fig. 7 ); femur I ad1 long and stout but setiform................................................................................... U. calypso ( Figs 6–9 )

- Sternal setae 1–3 not elongate, setiform; femur 1 ad1 apically bifid............................................. 3

3. Trochanter I dorsal seta apically bifid........................................................... U. species B 1

- Trochanter I dorsal seta simple.......................................................................... 4

4. Jx accessory dorsal setae absent....................................................... U. telemachus ( Fig. 44 )

- Jx accessory dorsal setae present........................................................................ 5

5. Podonotal z3 present, inner palp trochanteral seta not broadened....................... U. autolycus sp. nov. ( Figs 1–5 )

- Podonotal z3 absent, palp trochanteral seta broad> 5 µm, even foliate.......................................... 6

6. Zv1 modified as a blunt peg-like seta.......................................................... U. species A 2

- ZvI not a blunt peg-like seta............................................................................ 7

7. Length of posteriormost setae flanking anal shield (Jv5) subequal to length of anal shield,> 100 µm; femur II ad1 apically bifid............................................................................................. U. ulixes

- Length of posteriormost setae flanking anal shield (Jv5), only half length of anal shield, <100 µm; femur II ad1 setiform................................................................................................. U. ulysses

8. Podonotal j2 and opisthonotal px 2–3 absent, unpaired Jx setae absent; pd3 genu IV absent, making eight setae on this segment; weakly thickened anterior setae on coxa II and III; femur IV ad2 setiform U. sisyphus

- Seta j2 and at least one of px 2–3 present, unpaired dorsal accessory setae present, leg setation essentially holotrichous (or hypertrichous on genu IV only), all coxal setae setiform; femur IV ad2 apically bifid............................... 9

9. Two pl setae on genu IV, making 10 setae on this segment.................................................. 10

- Single pl setae on genu IV, making 9 setae on this segment.................................................. 11

10. Inner palp trochanteral setae is distinctly broadened (<5 mm wide), though not foliate. Primary metapodal platelet a narrow oval, idiosomal length <850 µm, with small cheliceral digits, movable digit <40 µm; femur I ad3 setiform.................................................................................................. U. penelope Domrow

- Inner palp trochanteral seta setiform, enlarged subcircular metapodal platelet, very large mites> 1200 mm idiosomal length, with massive chelicerae, movable digit> 240 µm; femur I ad3 apically bifid....................... U. laertes Domrow

11. At least st5 and Zv1 on genito-ventral shield................................................ U. anticlea Domrow

- Only st5 on genito-ventral shield....................................................................... 12

12. Movable digit broad, scoop-shaped with teeth on both paraxial and antiaxial edges, trochanter IV pl setiform............................................................................................. U. theoclymenus sp. nov.

- Movable digit narrow, trochanter IV pl apically bifid......................................... U. euryclea sp. nov.

1 Ulyxes species B , is only known from a single female (QM S99209 ) from a tree hollow den used by Trichosurus vulpecula johnstoni at Massey Creek, Queensland.

2 Ulyxes species A , brief morphological notes are provided at the end of this section.

Figures

FIGURES 1–5. Ulyxes autolycus female. 1, dorsum, note gland pores (gd), holotype, scale = 100 µm; 2, gnathosoma, note fimbriae with inflated tips (f), labrum (la), paratype, scale = 50 µm; 3, chelicera, holotype, scale = 50 µm; 4, epistome, paratype, scale = 50 µm; 5, venter, holotype, suture (s) marking top of tritosternal base, exopodal IV shown on LHS only, scale = 100 µm.

FIGURES 6–9. Ulyxes calypso female ex Petaurus norfolcensis, Greenbank, QLD. 6, dorsum, scale = 100 µm; 7, venter, scale = 100 µm; 8, hypostomal area of gnathosoma, note fimbriae (f) on lateral arms of internal malae with expanded tips, and foliate trochanteral setae (pointers); 9, femur III, note apically bifid ad1, scale = 10 µm.

FIGURES 10–15. Ulyxes euryclea female. 10, dorsal shield, holotype, note prominent gland pores (gd) posterolaterad px2, scale = 100 µm; 11, epistome, nest 245, scale = 50 µm; 12, chelicera, axial view, paratype, nest 87, scale = 50 µm; 13, tritosternum, suture (s) marking top of tritosternal base, nest 87, scale = 50 µm; 14, gnathosoma, scale = 100 µm; 15, ventral idiosoma, holotype, scale = 100 µm.

FIGURES 16–21. Ulyxes euryclea female ex Glossy Black Cockatoo nest, Kangaroo Is, nest 245; 16, chelicerae, scale = 10 µm; 17, post-stigmatal plate showing gutter linking median (m) and posterior pore-like structures (only median visible in superficial SEM view) scale = 10 µm; 18, femur IV with apically bifid ad1 and ad2, scale = 10 µm; 19, habitus, ventral view, scale = 100 µm; 20, sclerotised plate-like structure at anterior pole of egg, rs = putative ramus sacculi, sf = putative sacculus foemineus, scale = 10 µm; 21, chelicera, anterior view showing apically divided tip, scale = 10 µm.

FIGURES 22–24. Ulyxes euryclea males: 22, venter, ex Leadbeater’s possum, Yellingbo, nest 486, scale = 100 µm; 23, femur II, ventral view, scale = 50 µm; 24, chelicerae, arrow indicates triangular tip of spermatodactyl, ex Long-billed Corella, Templestowe, nest 87, scale = 50 µm.

FIGURES 25–27. Ulyxes euryclea male ex Glossy Black Cockatoo nest, Kangaroo Island, nest 245: 25, ventral body, scale = 100 µm; 26, genital opening, scale = 10µm; 27, femur II, ventral view, scale = 10µm.

FIGURES 28–29. Ulyxes laertes male. 28, venter, Mt Clunie, nest 409, scale = 100 µm; 29, epistome, scale = 50 µm.

FIGURES 30–33. Ulyxes laertes. 30, male chelicera, Mt Clunie, nest 409, scale = 100 µm; 31, female chelicera, Tenison Woods Mt, scale = 100 µm; 32, male gnathosoma, nest 409, scale = 50 µm; 33, female gnathosoma, Tenison Woods Mt, scale = 50 µm.

FIGURES 34–37. Ulyxes laertes male, Mt Clunie, nest 409; 34, habitus, dorsal view, scale = 100 µm; 35, chelicerae, scale = 10 µm; 36, epistome, scale = 10 µm; 37, femur III ad1 apically bifid seta, scale = 10 µm.

FIGURES 38–42. Ulyxes penelope male, Boho, Victoria. 38, chelicera, scale = 50 µm; 39, gnathosoma, suture (s) marking top of tritosternal base, scale = 50 µm; 40, venter, scale = 100 µm; 41, femur II dorsal view, scale = 50 µm; 42, tibia and tarsus II ventral view, scale = 50 µm.

FIGURES 43–46. Ulyxes telemachus ex Antechinus stuartii, Kioloa, NSW. 43, female hypostomal area of gnathosoma, note broadened trochanteral setae (pointers), scale = 10 µm; 44, female habitus, dorsal view, note prominent gland pores (gd), scale = 100 µm; 45, female venter, scale = 100 µm; 46, male venter, scale = 100 µm.

FIGURES 47–51. Ulyxes theoclymenus holotype female. 47, dorsal shield, unpaired Jx setae indicated by x’s, scale = 200 µm; 48, chelicera, axial-ventrolateral view, scale = 50 µm; 49, epistome, scale = 50 µm; 50, gnathosoma, scale = 50 µm; 51, ventral idiosoma, suture (s) marking top of tritosternal base, exo- and endopodal shields shown on LHS only, scale = 200 µm.

FIGURES 52–57. Male chelicerae. 52, Ulyxes telemachus, Kioloa, NSW;53, U. penelope, Boho, Victoria; 54, U. ulixes Bauple SF, Queensland; 55, U. sisyphus, Timbillica; 56, U. euryclea; 57, U. laertes, Mt Clunie, NSW. All to same scale bar = 100 µm.

FIGURES 58–59. 58, Ulyxes calypso genu IV, Bairnsdale, Victoria, QM S58980, scale = 100 µm; 59, U. sisyphus genu IV, Timbillica, female paratype, QM S58771, scale = 50 µm.