Texanobathynella aaronswinki, Camacho & Mas-Peinado & Hutchins & Schwartz & Dorda & Casado & Rey, 2021

Camacho, A. I., Mas-Peinado, P., Hutchins, B. T., Schwartz, B. F., Dorda, B. A., Casado, A. & Rey, I., 2021, New stygofauna from Texas, USA: three new species of Parabathynellidae (Crustacea: Bathynellacea), Journal of Natural History 55 (15 - 16), pp. 979-1007 : 993-997

publication ID	https://doi.org/ 10.1080/00222933.2021.1928316
DOI	https://doi.org/10.5281/zenodo.5496913
persistent identifier	https://treatment.plazi.org/id/03924334-DA27-FF96-FF60-FB2CFEF3FD99
treatment provided by	Plazi
scientific name	Texanobathynella aaronswinki
status	sp. nov.

Treatment

Texanobathynella aaronswinki sp. nov. Camacho and Hutchins, 2020

http://zoobank.org/ urn:lsid:zoobank.org:act:74A8B360-D749-4576-9987-AC02460B82E7

Material examined ( Table 1)

Type locality. Sessom Creek , Hays County, Texas, USA ( WGS 84 29.88996ºN, − 97.93596ºE, 177 m amsl): holotype male ( MNCN 20.04 View Materials /20165 slide and MNCN / ADN 54863 DNA extract) and (two male and one female paratypes. Coll. by B. Hutchins and B. Schwartz, 21 July 2015 (sample 150.721-H1). GoogleMaps

Other localities: South Llano River, Kimble County, Texas, USA ( WGS84 30.45342, −99.80060, 520 m amsl): two females, one each from samples 160.415-H2 and 160.415- H3 GoogleMaps . Same collectors, 15 April 2016.

All four specimens examined (three females and one male) ( Table 1) belong to the type series: four slides (morphological type series MNCN 20.04 View Materials /20165 to MNCN 20.04 View Materials /20168), together with four DNA extractions from the specimens used for molecular analysis (DNA types MNCN / ADN 54862, MNCN / ADN 54863, MNCN / ADN 54865 and MNCN / ADN 54866) (see Table 1) .

Description. Body elongated, segments widening towards posterior end. Head longer than broad.

Antennule ( Figure 4 View Figure 4 (a)) 7-segmented; first three segments much longer than last four segments combined; first segment longest; third segment similar in length to last segment, but triple in width; fifth segment shortest, with four smooth setae; inner flagellum trapezoidal; setation as in Figure 4 View Figure 4 (a); segments five with two aesthetascs and segments 6 and 7 with three terminal aesthetascs.

Antenna ( Figure 4 View Figure 4 (b)) 3-segmented, segments similar in length; first two segments without setae, third segment slightly longer than other two, with four setae, of which three terminal, one plumose and the other smooth.

Labrum ( Figure 4 View Figure 4 (c)). Almost flat, with 10 main teeth, of which all bicuspidate except two central, and lateral-most at each side that are multicuspidate.

Mandible ( Figure 4 View Figure 4 (d)). Pars incisiva with four well-developed teeth and very thin proximal tooth as in Figure 4 View Figure 4 (d); pars molaris with seven uneven claws, two most proximal setulose, and joined basally; mandibular palp not exceeding pars incisiva.

Maxillule ( Figure 4 View Figure 4 (f)). Proximal endite with four unequal claws; distal endite with five claws, of which two apical smooth, the rest denticulate; three simple unequal setae placed subdistally on outer margin of endite, as figured.

Maxilla ( Figure 4 View Figure 4 (g)) 3-segmented; setal formula: 1, 2 + 1, 13.

Thoracopods I–VII ( Figure 5 View Figure 5 (a–g)). Well developed, increasing gradually in length from ThI to ThIII ( Figure 5 View Figure 5 (a–c)); ThIV ( Figure 5 View Figure 5 (d)) to VII ( Figure 5 View Figure 5 (g)) similar in length; ThI without epipod; epipod well developed on ThII to VII, reaching a little more than half length of basipod. Basipod of all Ths with one short, smooth terminal seta. Exopod 2-segmented (ThI, VI, VII; Figure 5 View Figure 5 (a,f,g)), 3-segmented (ThII–ThV; Figure 5 View Figure 5 (b–e)); exopod of ThI–III, VI and VII shorter than corresponding endopod, rami similar in length in ThIV–V; all exopodal segments with one barbed seta (with groups of ctenidia at base) and one short and smooth outer seta, except last segment, which has a long barbed seta and a shorter plumose seta. Endopod of all thoracopods 4-segmented, first segment small, second and third long and similar in length, both with cluster of strong spinules along outer margin; fourth segment reduced with two strong smooth claws and one simple seta; outer seta of second segments of Th I–VII plumose. Setal formula of endopod as follows:

ThI 1 + 1/1 + 1/1 + 0/3(1)

ThII–VII 0 + 0/0 + 1/0 + 0/3(1)

Male thoracopod VIII ( Figure 4 View Figure 4 (h,i)). Rectangular, 1.5 times as long as wide, comprising basipod with both exopod and endopod inserted on posterior side of segment. Proximal region of basipod prolonged anteriorly onto penial complex, with three lobes: subrectangular outer lobe fused with basipod, placed adjacent to exopod in internal view; small dentate lobe covered with small terminal ‘tubercles’ and rounded inner lobe with a small bulge on distal end. Basipod not very short, with seta implanted close to insertion of endopod; latter small and with two setae; exopod, only visible on the back side of basipod, reduced to a small conical process.

Female thoracopod VIII ( Figure 5 View Figure 5 (j)). Trapezoidal, unsegmented, with three small teeth on distal end.

Pleotelson. Without ventral seta. Anal operculum not pronounced, almost flat.

First pleopods. Absent.

Uropod ( Figure 5 View Figure 5 (h)). Sympod 3.5 times as long as wide and 2.5 times longer than rami, with six unequal barbed spines, distal spines twice longer than rest. Rami equal in length; endopod terminating in lancet-shaped spine, with two barbed and one plumose setae at base; exopod with three barbed setae.

Furca ( Figure 5 View Figure 5 (i)). Rami almost triangular, each with six barbed spines, terminal two longer than rest; two unequal plumose setae implanted dorsally on each ramus, more internal seta reduced.

Etymology. The species is named after Aaron Swink, junior researcher, who played a major role in the sampling of hyporheic sites in Texas and educated youth about groundwater ecology for 5 years as Assistant Director for the Edwards Aquifer Research and Data Center’s education programme. The epitheton is a noun in the genitive singular masculine.