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<br />Glaridacris confusus Hunter,
<br />1929 (4/46); Monobothrium
<br />differtus Hunter, 1929 (5/46),
<br />,)led. Biacetabulum giganteum,
<br />tional records for Arkansas.
<br />assisted and identified speci-
<br />zinia Polytechnic Institute and
<br />RIVER SQUAWFISH AND
<br />d AND COLORADO RIVERS
<br />fishes of the American South-
<br />of which are currently listed
<br />threatened, or are currently
<br />mation on 1978 collections of
<br />ind the razorback sucker, from
<br />cius, was once quite common
<br />:y, it is considered extinct in
<br />eacon, Science 159:1424-1432,
<br />alnaker, Trans. Am. Fish Soc.
<br />Mile Colorado River squawfish
<br />km downstream from Aneth,
<br />.'er and McElmo Creek. The
<br />was 177 mm in total length
<br />of this species from the main-
<br />Juan include early works b,
<br />Evermann and Runner (Bull-
<br />records? of this species fron
<br />(Southwest. Nat. 5:174175
<br />ico; four adults from the Say.
<br />New Mexico Game and Fis-,
<br />at, Utah, in 1961 (Sigler an,
<br />ie specimen near Bloomfielc
<br />New Mexico Dep. Game an
<br />rs taking adults of this specie
<br />ly as 1977 (Bill Silvey, per
<br />once quite abundant in ti
<br />lid Fish Dep., 1973). Curren,
<br />to River, below Lake Moha-,
<br />i Lake Mohave, and in smai
<br />back sucker 100 m upstrea:
<br />imens were observed but we
<br />1 be spawning. This represer.
<br />-ion.
<br />The first specimen of X. texanus was taken from the Grand Canyon region of
<br />the Colorado River, from Bright Angel Creek, in 1944 by an angler. The second
<br />specimen was collected from the confluence of the Colorado and Paria rivers just
<br />after the impoundment of Glen Canyon Dam in 1963 (W. L. Minckley, pers.
<br />comm.). Hybrid specimens (Xyrauchen texanus x Catostornous latipinnis)also
<br />were taken from this last locality in 1966 by the Arizona Game and Fish Dep.,
<br />and by Suttkus et al. (Colorado Riv. Res. Prog. Tech. Rep. 5, 1976), who con-
<br />sidered this species extinct from the base of Glen Canyon Dam to Separation
<br />Rapids (Colorado River mile 240).
<br />These recent collections (1) document reproduction, (2) indicate that the
<br />Colorado and San Juan Rivers still contain suitable habitat for these native species,
<br />and (3) illustrate that the native ichthyofauna of the Southwest still exists in
<br />many areas throughout its former range despite the increasing pressure from
<br />exotic introductions and human activities.
<br />This research was supported by grants from the Nat. Park Serv. (contr. no.
<br />CX821070012); the Bureau of Reclamation, Boulder City Office (contr. no. 7-07-30-
<br />X0026); and by VTN Consolidated, Irvine, California, through the Bureau of
<br />Reclamation, Amarillo Office.--C. O. Minckley and S. W. Carothers, Museum of
<br />Northern Arizona, Route 4, Box 720, Flagstaf
<br />fAZ 86001.
<br />THE ASSOCIATED GASTROPOD FAUNA OF THE SANTA ANA NA-
<br />TIONAL WILDLIFE REFUGE WITH NOTES ON A COLONY OF THE
<br />SNAIL, HELICINA ORBICULATA.-The gastropod faun
<br />a of Santa Ana Nat.
<br />'
<br />Wrldl. Refuge, Hidalgo
<br />Co.
<br />Texas, includes at least 18 species representing 12
<br />families (Table 1). Aquatic gastropods were collected from the levee ditch along
<br />the N boundary of the refuge proper. Delnicki (Auk, in press) and Hiller (Texas
<br />Parks Wildl. 34[10]':16-17, 1976) reported Hook-billed Kites (Chondrohierax
<br />uncinatus) feeding here on Rhabdotus alternatus (Say). I deposited a sample of
<br />shells from beneath a kite's feeding perch and other specimens with the Dallas
<br />Mus. Nat. Hist. (DMNH). Snail identifications followed Cheatum and Fulling-
<br />ton (Dallas Mus. Nat. Hist. Bull. 1 [Supplement]: 18 pp., 1971; Dallas Mus.
<br />Nat. Hist. Bull. 1[1]: 74 pp., 1971; Dallas Mus. Nat. Hist. Bull. 1[21: 67 pp.,
<br />1973), Fullington and Pratt (Dallas Mus. Nat. Hist. Bull. 1[3]: 48 pp., 1974), and
<br />Burch (How to know the eastern land snails, Brown, Dubuque, 1962).
<br />Live terrestrial gastropods were difficult to locate except after rains. In Sep.
<br />1977 many extant species were seen which had been found only as shells earlier
<br />in drier periods. Additional observations in other habitats under favorable moisture
<br />conditions likely will produce more species.
<br />Fullington and Pratt (1974) noted the apparent absence of extant colonies of
<br />Helicina orbiculata (Say) in the Rio Grande Delta and most of South Texas. On
<br />21 Nov. 1976, while walking through Santa Ana Nat. Wildl. Refuge, I noticed
<br />a number of inactive Helicina. I have not observed extant individuals elsewhere
<br />in Delta counties in 3.5 yr of field work. A sample of 15 specimens was collected
<br />and deposited in the DMNH.
<br />. Helicina orbiculata were attached to Texas ebony trees, Pithecellobium flexi-
<br />caule (Benth.) Coutl., as high as 2 m above the ground. Personal observations
<br />of H. orbiculata in Austin, Travis Co., Texas, showed the snail spending con-
<br />siderable time on tree trunks and branches. Cheatum (in Pilsbry, Acad. Nat. Sci.
<br />687
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