Phallocryptus sublettei ( Sissom, 1976 ) Sissom, 1976

Rogers, D. Christopher, 2003, Revision of the thamnocephalid Genus Phallocryptus (Crustacea; Branchiopoda; Anostraca), Zootaxa 257, pp. 1-14 : 5-7

Phallocryptus sublettei ( Sissom, 1976) new combination

( Figure 1 b, 3a­f)

Branchinella sp. Sublette & Sublette, 1967

Branchinella sp. Sissom, 1971

Branchinella sp. Horne, 1974

Branchinella sublettei Sissom, 1976

“ Branchinella arlica ” Belk (Undescribed holotype (143837) and paratypes (143838) deposited at the USNM)

Diagnosis: Male: Cephalic appendages absent. First antennae three to four times as long as eye plus stalk. Second antennal proximal segment subequal in length to first antennae, subcylindrical, medial surface with small spines. Second antennal distal segment twice as long as proximal segment, arcuate, curving medially, and tapering to an acute apex. Medial surface of distal segment with a longitudinal row of small denticulate spines. Praeepipodite entire. Ventral surface genital segments without tubercles. First abdominal segment (first post­genital segment) without a medial­ventral spine–like projection on the distal margin of the segment. Each abdominal segment with a stout, distal, ventro­lateral spine, directed ventro­laterally.

Female. First antennae nearly four times as long as eye plus stalk, subequal in length to second antennae. Second antennae nearly joined basal­medially, slightly produced medially. Second antennae lamellar, bearing a basal­lateral slightly elevated region with scattered spines, apex tapering to a sub­acute tip. Brood pouch triangulate­pyriform, with paired basal­lateral and a single basal­medial projection. Each brood pouch projection is directed ventro­posteriorly. Brood pouch extends to the third or fourth abdominal segment, tapering posteriorly to apex. Gonopore produced distally, with dorsal “lip” longer than ventral lip. Abdominal segments without ventral­lateral spines.

Resting cyst: Sub­spherical with shallow sub­oval depressions, with a slit shape in the base of each depression. Depressions are separated by thin ridges.

Type Locality. USA, Texas, a saline playa (pan) near Tahoka.

Type. Holotype, allotype, and paratypes (USNM­143958, 143959 and 143960, respectively) deposited at the USNM.

Distribution. USA, Texas, Lynn, Terry and Gaines Counties on the Llano Estracado (the northwestern Texas highlands) ( Sublette & Sublette, 1967; Horne, 1974), and Hudspeth County ( Belk & Sissom, 1992). New Mexico: Otero County at Crow Flats (Rogers & Lang, in prep). The saline habitats at Crow Flats are nearly contiguous with the Hudspeth County, Texas saline pools. This species may also occur in México.

Habitat. Ephemeral saline lakes and pools.

Activity Period. August to October, depending upon rain fall.

Comments. Coocurrs with Branchinecta campestris Lynch, 1960 ( Sublette & Sublette, 1967) , Artemia franciscana Kellogg, 1906 and Streptocephalus texanus Packard, 1871 ( Horne, 1974) .

Conservation status. This species appears to be relictual, currently reported from only seven sites in Texas and New Mexico ( Sublette & Sublette, 1967; Horne, 1974; Belk & Sissom, 1992; Rogers & Lang, in prep). As it stands, this species meets the International Union for the Conservation of Nature and Natural Resources (IUCN) red list criteria for designation as a VU 2D2 species (IUCN, 2000). That is to say, this taxon is vulnerable due to the population being very small and restricted, that may be prone to the effects of human activities or stochastic events within a short period of time.

Material examined: USA: NEW MEXICO: Otero County: Crow Flats, numerous cysts, 20 September 2000, D.C. Rogers, B. K. Lang. TEXAS Hudspeth County: Crow Flats at Highway 82/180, 30 males, 30 females, 23 September 1986, D. Belk.

Figures

FIGURE 1. Phallocryptus, male genitalia: A) P. w r i g h t i; B) P. sublettei; C) P. s p i n o s a.