Diamphidaxona sabinalensis, Smith, Ian M. & Cook, David R., 2006

Smith, Ian M. & Cook, David R., 2006, North American species of Diamphidaxona (Acari: Hydrachnida: Hygrobatidae), Zootaxa 1279, pp. 1-44 : 10-11

Diamphidaxona (s. s.) sabinalensis sp. nov.

( Figs. 30–34 )

Description. Male with character states of Diamphidaxona (s. s.) (female unknown). Dorsal edge of camerostome rounded anteriorly and not projecting to anterior end of idiosoma ( Fig. 31 ). Pedipalps with tibia bearing one ventral seta and tarsus with ventral spine­like seta bearing 2 strongly recurved denticles ventrally ( Fig. 32 ). Dorsal shield with anterior plate of same width as posterior plate and rounded anteriorly ( Fig. 30 ). Ventral shield with suture lines between third and fourth coxal plates with medial loops deeply arched and lateral loops U­shaped and open anteriorly ( Fig. 31 ). Projections covering insertions of fourth pair of legs with anterior extensions long and directed anteriorly parallel to edges of ventral shield ( Fig. 31 ). Genital field of males fused with ventral shield ( Fig. 31 ). Measurements of holotype: Male (n=1): Length/width anterior dorsal plate 149/ 238, length/width posterior dorsal plate 297/243, length/width ventral shield 436/282, length/width genital field 69/104. Lengths pedipalp segments: Tr 15, Fe 53, Ge 35, Ti 58, Ta 25. Lengths leg segments: ITr 33, IBFe 53, ITFe 55, IGe 58, ITi 60, ITa 69; IITr 38, IIBFe 53, IITFe 50, IIGe 58, IITi 58, IITa 68; IIITr 38, IIIBFe 40, IIITFe 45, IIIGe 58, IIITi 60, IIITa 75; IVTr 75, IVBFe 70, IVTFe 75, IVGe 85, IVTi 83, IVTa 75.

Female. Unknown.

Types. Holotype: Male from Can Creek beside East Trail, Lost Maples State Natural Area, near Vanderpool, Bandera Co., Texas on 27 May 1998 by IMS (slide, CNC).

Etymology. Named for the Sabinal River of which Can Creek is a tributary.

Distribution. Known only from the type locality.

Remarks. Adults of Diamphidaxona sabinalensis resemble those of D. dolichosoma and the following four species in that the projections covering the insertions of the fourth pair of legs are long and extend anteriorly parallel to the edges of the ventral shield, but differ in that the ventral spine­like seta on the tarsus of the pedipalp bears two strongly recurved denticles ventrally.

Figures

FIGURES 30 – 34. Diamphidaxona (s. s.) sabinalensis sp. nov., adult male. 30, dorsal shield; 31, ventral shield and genital field; 32, pedipalp; 33, leg I; 34, distal segments of leg IV.