Species List and Distribution data from: Meyers, M. and W. P. McCafferty. 2008. Mayflies (Ephemeroptera) of the far western United States. Part 3: California. Trans. Amer. Entomol. Soc. 134: 337-430.
AMELETIDAE
Species of Ameletus are common to California streams, and western North America streams in general (see McCafferty et al. 2012). Quite often one can find species of Ameletus in small pools on the edge of the stream (personal observation).
Zloty and Pritchard (1997) provided a very useful key to the larvae and adults of Ameletus. Even though the key is focused on species from Alberta, it can be used for California species if one keeps in mind that A. dissitus, A. imbellus, A. falsus, A. doddsianus, and A. amador are not included in the key. When identifying the larvae, one can start with the Zloty and Pritchard key (1997), and then use the original descriptions for the California species not included in their key (details given below). Unfortunately certain larval characteristics used by Zloty (e.g., spines on the posterior margins of the sternites–see couplet 3 in Zloty and Pritchard 1997) are not described in the older literature; however, quite often the dorsal color patterns can be quite useful. Adults are more or less readily identified by using the distinctive genitalia, and in some cases, wing coloration can actually be quite useful.
Day’s (1956) key in Usinger’s Aquatic Insects of California is just too incomplete to use, and it does not include larvae.
The distribution data of Ameletus in California is likely incomplete as the larvae, the most commonly collected stage, can be challenging to identify, and some larvae have not been described.
Ameletus amador Mayo
Type Locale: Amador Co., Dry Cr near Dry Town.
California Distribution: Amador, Calaveras, Fresno, Mariposa, Mendocino, Shasta, Siskiyou, Tulare, Tuolumne
Adult Description: Zloty (1996) included this species in his key to North American Ameletus adults. He provided a figure of the male genitalia (Fig. 8A, 20). Mayo (1939) included a whole body lateral view of the adult (Fig. 12), plus an excellent figure of the male genitalia (Fig. 10).
Larva: In Mayo’s (1939) description of this species, she included a very useful figure of the larvae (see Fig. 9). The larval color pattern is distinct, and I will use this as my starting point.
Identification Notes: Adults are best keyed using Zloty (1996), even though Day (1956) keyed the California species known at that time. The Zloty (1996) key is more comprehensive. At present there is no larval key that includes A. amador, but the larval coloration is rather distinct (see Fig. 9 in Mayo 1939), making this species one of the easier ones in the genus to identify in California.
Ecological notes: This species has been collected from ephemeral streams in the Sierra Nevada foothills (pers. observ.). The type locale, Dry Creek, is appropriately named as it is dry by the end of summer.
References:
Day, W. C. 1956. Ephemeroptera. Pages 79-105 In: Aquatic Insects of California. R. L. Usinger (ed). University of California Press, Berkley.
Mayo, V.K. 1939. New Western Ephemeroptera. Pan-Pacific Entomol. 15: 144-154.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Ameletus andersoni Zloty
Type Locale: Washington
California Distribution: Mendocino
Adult description: Zloty (1996) provided a key to and description of the adult, with figures of the genitalia (8D, 21) and wing color pattern (Fig. 45B). There is no formal description of the larvae, although Zloty (1996) noted larvae were collected along with the adults. Zloty (1996) noted that habitat information can be found in Dieterich (1992).
Larval Description: none.
Identification Notes: Personally I have not seen this species and so have no comments based on experience. I suggest use Zloty’s (1996) key. In California this species is only known from the far north-western corner, and so one should be aware of this species if collecting in that region.
Ecological Notes: Dieterich and Anderson (2000) described this species as being found in temporary streams in Oregon, and so it is possible this species can be found in temporary streams in California.
References:
Dieterich, M. 1992. Insect community composition and physicochemical processes in summer-dry headwater streams of western Oregon. PhD dissertation, Oregon State University, Corvallis, OR. 202p.
Dieterich, M and Anderson 2002. The invertebrate fauna of summer-dry streams in western Oregon. Archiv für Hydrobiologie 147 (not easily available on-line)
Ameletus bellulus Zloty 1996
Type Locale: Oregon
California Distribution: Amador, Butte, El Dorado, Humboldt, Inyo, Kern, Marin, Mariposa, Mendocino, Mono, Monterey, Nevada, Placer, San Bernardino, San Luis Obispo, Santa Clara, Sierra, Siskiyou, Stanislaus, Sonoma, Tehama, Trinity, Tulare.
Adult Description: Zloty (1996) described and provided a key to the adults, including figures for the male genitalia (Fig. 22) and wings (Fig. 46B). An additional key to the adults was published by Zloty and Pritchard (1997), albeit the key is limited to the species found in Alberta, Canada. Zloty’s (1996) key is the one to use.
Larval Description: Zloty and Pritchard (1997) described the larvae and provided a key to the larval species from Alberta. The dorsal abdominal color pattern can be found in Fig. 17a. When using the Zloty and Pritchard’s key (1996), one just needs to keep a description of Day’s (1952, 1956) and Mayo’s (1939, 1952) on hand to verify the species is not one of those. In southern California it is possible A. falsus might be found eventually. A larval description and figures of this species can be found in Allen and Chao (1981) as A. falsus and A. sp. “C” (Zloty 1996).
Identification Notes: The key by Zloty and Pritchard (1997), although focused on species known from Alberta, can work in California as long as one uses this key and having the descriptions of the species described by Mayo and Day on hand. Zloty’s (1996) key works well for the California species as that key includes all known western USA species of Ameletus.
References:
Day, W. C. 1952. New species and notes on California mayflies. Pan-Pacific Entomol. 28: 17-39.
Day, W. C. 1956. Ephemeroptera. Pages 79-105 In Aquatic Insects of California. R. L. Usinger (ed). University of California Press, Berkley.
Mayo, V. K. 1939. New western Ephemeroptera. Pan. Pacific Entomol. 15: 145-154.
Mayo, V. K. 1952. New western Ephemeroptera, III. Pan-Pacific Entomol. 23: 93-103.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and G. Pritchard. 1997. Larvae and adults of Ameletus mayflies (Ephemeroptera: Ameletidae) from Alberta. Can. Entomol. 129: 251-289.
Ameletus celer McDunnough
Type Locale: Alberta, Canada (McDunnough 1934)
California Distribution: Contra Costa, Shasta, Solano.
Adult Description: Traver (1935) did key the adult and includes a figure of the male genitalia (Fig. 116), but Zloty’s (1996) key is the one to use. It is the most complete and with more detailed figures (Figs 2, 11, 41, and 45a).
Larval Description: As with the adults, the larvae are keyed in Traver (1935), but again, the best larval key and description will be found in Zloty and Pritchard (1997). The dorsal and ventral abdominal color patterns are given in Figs. 17B and 17C.
Notes: Day (1956) did not include this species in his work on California as it was unknown from the state at that time. Meyer and McCafferty reported it in 2008 (Meyer and McCafferty 2008).
References:
McDunnough, J. 1934. New species of North American Ephemeroptera IV. Can. Entomol. 66: 154-164, 181-188.
Meyers, M. and W. P. McCafferty. 2008. Mayflies (Ephemeroptera) of the far western United States. Part 3: California. Trans. Amer. Entomol. Soc. 134: 337-430.
Traver, J. R. 1935. Part II. Systematic. Pp. 237-739 in The Biology of Mayflies by Needham, J.G., J. R. Traver, and Y.-C. Hsu. Comstock Publishing Company, Inc. Ithaca.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and G. Pritchard. 1997. Larvae and adults of Ameletus mayflies (Ephemeroptera: Ameletidae) from Alberta. Can. Entomol. 129: 251-289.
Ameletus cooki McDunnough
Type Locale: Montana
California Distribution: Alpine, Amador, Contra Costa, Humboldt, Marin, Mariposa, Plumas, Siskiyou
Adult Description: This species was originally described by McDunnough (1929), keyed by Traver (1935), but the best key and figures are found in Zloty (1996).
Larval Description: The best larval key and description will be found in Zloty and Pritchard (1997). The dorsal and ventral abdominal color patterns are given in Figs. 17D and 17E. As with identifying any species of California Ameletus using Zloty and Pritchard (1997), one must be aware of the species described by Day (1952, 1956) and Mayo (1939, 1952).
Notes: As with A. celer, this species had not been reported from California until the work by Meyer and McCafferty (2008).
References:
Day, W. C. 1952. New species and notes on California mayflies. Pan-Pacific Entomol. 28: 17-39.
Day, W. C. 1956. Ephemeroptera. Pages 79-105 In Aquatic Insects of California. R. L. Usinger (ed). University of California Press, Berkley.
Mayo, V. K. 1939. New western Ephemeroptera. Pan. Pacific Entomol. 15: 145-154.
Mayo, V. K. 1952. New western Ephemeroptera, III. Pan-Pacific Entomol. 23: 93-103.
McDunnough, J. 1929. Notes on North American Ephemeroptera with descriptions of new species, II. Can. Entomol. 61: 169-180.
Meyers, M. and W. P. McCafferty. 2008. Mayflies (Ephemeroptera) of the far western United States. Part 3: California. Trans. Amer. Entomol. Soc. 134: 337-430.
Traver, J. R. 1935. Part II. Systematic. Pp. 237-739 in The Biology of Mayflies by Needham, J.G., J. R. Traver, and Y.-C. Hsu. Comstock Publishing Company, Inc. Ithaca.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Ameletus dissitus Eaton
Type Locale: Marin Co., San Geronimo
California Distribution: Marin, Napa, Solano, Sonoma, Stanislaus, Yolo
Adult Description: Zloty (1996) provided the best key for identifying the adults. Day (1956) keyed out the adult and provided a figure of the male genitalia (Fig. 3:12a); the Zloty (1996) key is more complete and works well for California species.
Larval Description: The larvae are still unknown. All California records are based on adults.
Identification Notes: Keep in mind the keys to the adults found in Traver (1935) and Day (1956) described a long slender spine on each of the penes, but Zloty (1996) did not use that character but instead emphasized the twisted hook at the end of the titillator (Fig. 24B). Presumably the trait Zloty (1996) emphasized is more distinct (I have not seen adults of this species and so cannot provide any comment).
References:
Day, W. C. 1956. Ephemeroptera. Pages 79-105 In Aquatic Insects of California. R. L. Usinger (ed). University of California Press, Berkley.
Traver, J. R. 1935. Part II. Systematic. Pp. 237-739 in The Biology of Mayflies by Needham, J.G., J. R. Traver, and Y.-C. Hsu. Comstock Publishing Company, Inc. Ithaca.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Ameletus edmundsi Zloty
Type Locale: Utah
California Distribution: Fresno
Adult Description: Zloty (1996) originally described this species and keyed the adults. Zloty and Harper (1999) includes this species in their key of adult Ameletus found in western Oregon.
Larval Description: The larvae have not been formally described nor is the species included in any key to help with identification. Meyers and McCafferty (2008) reported adults and larvae from a lake in the Sierra Nevada’s.
References:
Meyers, M. and W. P. McCafferty. 2008. Mayflies (Ephemeroptera) of the far western United States. Part 3: California. Trans. Amer. Entomol. Soc. 134: 337-430.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and F. Harper. 1999. Two new Ameletus mayflies (Ephemeroptera: Ameletidae) from western North America. Can. Entomol. 131: 1-9.
Ameletus imbellis Day
Type Locale: Napa
California Distribution: Alpine, Colusa, Kern, Madera, Mono, Napa, Santa Clara, Shasta, Yolo
Adult Description: Day (1952) provided the first description, which included a figure of the wing (Plate V, Fig. 2) and the male genitalia (Plate V, Fig. 5). Zloty (1996) keyed the species and provided a figure of the genitalia (Fig. 27).
Larval Description: There is no description of the larvae available. Day (1952) noted larval exuviae were collected with the species, and Zloty (1996) concluded the exuviae was not complete enough to use for identification purposes or to be able to provide a larval description.
References:
Day, W. C. 1952. New species and notes on California mayflies. Pan-Pacific Entomol. 28: 17-39.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Ameletus majusculus Zloty
Type Locale: Alberta, Canada
California Distribution: Humboldt, Inyo, Madera, Napa, Siskiyou
Adult Description: Zloty (1996) described the species, including it in a key to adults and providing figures of the male genitalia in Fig 32 of Zloty (1996) and Fig. 7 in Zloty and Pritchard (1997). This species is also keyed in Zloty and Pritchard (1997). Zloty (1996) also figured sternites 2-4 (Fig 43)
Larval Description: The larvae were described by Zloty and Pritchard (1997), with a figure of the dorsal abdominal color pattern (Fig. 19A).
Identification Notes: Larvae and adults are keyed in Zloty and Pritchard (1997). In this paper they describe this species as one of the largest Ameletus species.
References:
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and G. Pritchard. 1997. Larvae and adults of Ameletus mayflies (Ephemeroptera: Ameletidae) from Alberta. Can. Entomol. 129: 251-289.
Ameletus minimus Zloty and Harper
Type Locale: Lane co. Oregon.
California Distribution: Humboldt, Mendocino
Adult Description: Zloty and Harper (1999) described the adult, providing a figure of the male genitalia (Fig. 1). In this paper they also included this species in a key to the celer group in western North America.
Larval Description: Zloty and Harper (1999) described the larvae and included a figure of the dorsal and ventral color patterns (see Fig. 3).
Identification Notes: Zloty and Harper (1999) described the larvae as being distinguished from other Ameletus by dorsal and ventral coloration, color pattern, and small body size. Body size generally must be used with caution, however. Body size may be a good rough sort but color pattern is usually more reliable.
Ecological Notes: In Oregon this species was collected with A. andersoni in first order streams. (Zloty and Harper 1999). They described the streams as not flowing during the summer months, and so this is likely a drought tolerant species.
References: Zloty, J. and F. Harper. 1999. Two new Ameletus mayflies (Ephemeroptera: Ameletidae) from western North America. Can. Entomol. 131: 1-9.
Ameletus pritchardi Zloty
Type Locale: Alberta, Canada
California Distribution: Contra Costa Co.
Adult Description: Zloty (1996) described the species, including it in a key to adults. This species is also keyed in Zloty and Pritchard (1997). In the 1996 paper, the male genitalia are in Fig. 14 and Fig. 8 (Zloty and Pritchard 1997). Adults are also included in a key to the celer group (see Zloty and Harper 1999).
Larval Description: The larvae were described by Zloty and Pritchard (1997), with a figure of the dorsal abdominal color pattern (Fig. 19B).
Identification Notes: Adults and larvae are keyed in Zloty and Pritchard (1997).
Ecological Notes: Zloty and Pritchard (1997) described this species as occurring in first or second order streams or side channels of those streams that dry up at the end of summer. This would be consistent with the habitat of Bollinger Cr, a typical California stream that is dry by the end of the summer.
References:
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and G. Pritchard. 1997. Larvae and adults of Ameletus mayflies (Ephemeroptera: Ameletidae) from Alberta. Can. Entomol. 129: 251-289.
Zloty, J. and F. Harper. 1999. Two new Ameletus mayflies (Ephemeroptera: Ameletidae) from western North America. Can. Entomol. 131: 1-9.
Ameletus shepherdi Traver
Type Locale: Santa Cruz
California Distribution: Mendocino, Santa Cruz, San Mateo, Siskiyou, Tehama
Adult Description: Traver (1934) originally described this species from Waddell Cr, a stream that empties directly into the Pacific Ocean (it’s quite pretty). She provided a figure of the male genitalia (Fig 19), and revised this figure for her 1935 publication (Fig. 117). Day (1956) included this species in his California key to the adults, effectively recreating the figure from Traver (1935) (Fig. 3:13b). Zloty’s (1996) update of the adult Ameletus included this species in his key, providing new figures of the genitalia (Fig. 16). This species is also included in Zloty’s key to Oregon adult Ameletus (Zloty and Harper 1999, Fig. 5c, 5d). Zloty (1996) also synonomized A. querulus McDunnough with this species.
Larval Description: An updated and more detailed description of the larva is warranted. A description is in Traver (1934 and 1935) but is of limited use.
Identification Notes: As with much of the older taxonomic literature, the original descriptions are of limited use.
References:
Day, W. C. 1956. Ephemeroptera. Pages 79-105 In Aquatic Insects of California. R. L. Usinger (ed). University of California Press, Berkley.
Traver, J. R. 1934. New North American species of mayflies (Ephemerida) J. Elisha Mitchell Sci Soc. 50: 189-255.
Traver, J. R. 1935. Part II. Systematic. Pp. 237-739 in The Biology of Mayflies by Needham, J.G., J. R. Traver, and Y.-C. Hsu. Comstock Publishing Company, Inc. Ithaca.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and F. Harper. 1999. Two new Ameletus mayflies (Ephemeroptera: Ameletidae) from western North America. Can. Entomol. 131: 1-9.
Ameletus similior McDunnough
Type Locale: Alberta, Canada
California Distribution: Amador, Butte, Inyo, Marin, Mendocino, Shasta, Siskiyou, Ventura
Adult Description: McDunnough (1928) provided the first description of this species, and Zloty (1996) updated the description and provided an updated figure of the male genitalia (Fig. 15 and Fig 11) in Zloty and Pritchard (1997). Ameletus monta Mayo was synonomized with this species, but Mayo (1952) in her description of A. monta included a figure of the male genitalia (Fig. 11) and the gill (Fig. 9).
Larval Description: Larvae are included in the key by Zloty and Pritchard (1997) Figs. 18C, D, and E show dorsal and ventral coloration. Mayo (1952), as A. monta, included a figure of the gill (Fig 9). The gill can be diagnostic, particularly where the mesal band occurs–either on the margin or more interior (see the key in Zloty and Pritchard 1997)
Identification Notes: Adults are included in Zloty and Pritchard (1997) and Zloty and Harper’s (1999) key to Oregon Ameletus.
References:
Mayo, V. K. 1952. New Western Ephemeroptera, III. Pan-Pac. Entomol. 23: 93-103.
McDunnough, J, 1928. The Ephemeroptera of Jasper Park, Alta. The Canadian Entomol. 60: 8-10.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and G. Pritchard. 1997. Larvae and adults of Ameletus mayflies (Ephemeroptera: Ameletidae) from Alberta. Can. Entomol. 129: 251-289.
Ameletus sparsatus McDunnough
Type Locale: Alberta, Canada
California Distribution: Alpine, Butte, Colusa, Contra Costa, Fresno, Glenn, Mariposa, Mendocino, Mono, Plumas, San Bernardino, San Luis Obispo, Santa Cruz, Shasta, Sierra, Tuolumne, Yuba
Adult Description: This species was originally described by McDunnough (1931). Traver (1935) figured the male genitalia (Fig. 118), and included this species in her key to adult Ameletus. Zloty (1996) provides the most useful description and key that includes this species, providing a new figure to the genitalia (Fig. 28) and wing coloration (Fig 46c). The adult is also included in Zloty and Pritchard (1997).
Larval Description: The larvae were also described by McDunnough, but in a later paper (McDunnough 1935). Zloty and Pritchard (1997) updated the description and figures, including it in their key to Alberta Ameletus (dorsal color pattern can be found in Fig. 21c.)
Identification Notes: Zloty (1996) described geographic variation in wing coloration. Wing variation in California populations has not been documented, however. See Zloty (1996) for details on adults and Zloty and Pritchard (1997) for details on separating this species from A. cooki and A. suffusus.
References:
McDunnough, J. 1931. New species of North American Ephemeroptera. The Canadian Entomol. 63: 82-93.
McDunnough, J. 1935. Notes on western species of Ephemeroptera. The Canadian Entomol. 67: 95-104.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and G. Pritchard. 1997. Larvae and adults of Ameletus mayflies (Ephemeroptera: Ameletidae) from Alberta. Can. Entomol. 129: 251-289.
Ameletus subnotatus Eaton
Type Locale: Colorado
California Distribution: Lake
Adult Description: Eaton (1885) originally described this species, but Spieth (1941) provided a much more useful description, including a figure of the genitalia (Figs. 5, 7). Zloty (1996) included this species in his key, redescribed the adult, and included a more detailed figure of the genitalia (Figs. 34, 36c.)
Larval Description: Zloty and Pritchard (1997) provided the first description of the larvae and included it in their key to the Alberta mayflies. In this paper is a very useful figure of the dorsal abdominal coloration (Fig. 20b).
Identification Notes: Spieth (1941) and Zloty (1996) both noted the figure of the genitalia in Traver (1935) was actually a different species (A. doddsianus).
Ecological Notes: Zloty and Pritchard (1997) noted this species was unusual in that it is found in larger streams. In California the North Fork of Cache Creek does not quite fit that profile, however.
References:
Eaton, A. E. 1883-1888. A revisional monograph of recent Ephemeridae or mayflies. Transactions of the Linnean Society of London, Zoology 2: 1-352.
Spieth, H. T. 1941. The North American ephemeropteran types of the Rev. A.E. Eaton. Annals Entomol. Soc. Amer. 34: 87-98
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and G. Pritchard. 1997. Larvae and adults of Ameletus mayflies (Ephemeroptera: Ameletidae) from Alberta. Can. Entomol. 129: 251-289
Ameletus suffusus McDunnough
Type Locale: British Columbia
California Distribution: Colusa, Contra Costa, Glenn, Humboldt, Lake, Madera, Marin, Mariposa, Mendocino, Monterey, Napa, Nevada, San Bernardino, Santa Clara, Siskiyou, Tulare, Ventura.
Adult Description: McDunnough (1936) originally described this species, and Zloty (1996) included this species in his key, providing a more detailed and useful figure of the male genitalia (Fig. 29). Additional figures of the adult can be found in Zloty and Pritchard (1997).
Larval Description: Zloty and Pritchard (1997) included it in their key of Alberta species, and provided the first description of the larvae, including dorsal coloration (Fig 20a).
Identification Notes: The abdominal coloration works well in California in separating this species from other Ameletus.
References:
McDunnough, J. 1936. Further notes on the genus Ameletus with descriptions of new species (Ephemeroptera). Canadian Entomol. 68: 207-211.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and G. Pritchard. 1997. Larvae and adults of Ameletus mayflies (Ephemeroptera: Ameletidae) from Alberta. Can. Entomol. 129: 251-289
Ameletus validus McDunnough
Type Locale: Alberta
California Distribution: Alpine, El Dorado, Fresno, Humboldt, Lake, Nevada, Mendocino, Placer, San Bernardino, San Mateo, Santa Clara, Siskiyou
Adult Description: McDunnough (1923) first described this species. Zloty (1996) and Zloty and Pritchard (1997) included this species in their key to adults, and updated the figures (see Fig. 7 in Zloty 1996).
Larval Description: Zloty and Pritchard (1997) were the first to describe the larvae and illustrated the dorsal color pattern (Fig. 18f).
Identification Notes:
In addition Day (1954) provided a figure of the genitalia (Plate III, Figs. 12-14). For the larvae, dorsal abdominal segments 8 and 9 are distinctive for this species.
Ecology: Day (1952) briefly describes the emergence of this species from Upper Truckee River, noting it seemed to prefer calm waters. In that paper he described how the larvae emerged from the water, crawling completely out and then emerging into the subimago.
References:
Day, W. C. 1954. New species and notes on California mayflies. II. Pan-Pacific Entomol. 30: 15-29.
McDunnough, J. 1923. New Canadian Ephemeridae with notes. Canadian Entomol. 55: 39-50.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and G. Pritchard. 1997. Larvae and adults of Ameletus mayflies (Ephemeroptera: Ameletidae) from Alberta. Can. Entomol. 129: 251-289
Ameletus vancouverensis McDunnough
Type Locale: British Columbia
California Distribution: Lake, Napa, Santa Clara, Sonoma, Siskiyou
Adult Description: McDunnough (1933) originally described this species. Zloty (1996) included this species in his adult key to western Ameletus. He also provided a more recent figure of the male genitalia (Fig. 30) and forewing (Fig. 47C).
Larval Description: The larvae remain undescribed, although they have been collected from California populations (see Meyer and McCafferty 2008).
Identification Notes: The wings are essentially completely pigmented with an amber color, although Zloty (1996) cautioned that in southern populations (e.g., California) coloration may be reduced. Day (1952) also provided a figure of the genitalia (Fig. 6, 6a), although he thought he was describing a new species (A. facilis). Zloty (1996) synonomized A. facilis with A. vancouverensis.
References:
Day, W. C. 1952. New species and notes on California mayflies (Ephemeroptera). Pan-Pacific Entomol. 27: 17-39.
McDunnough, J. 1933. New species of North American Ephemeroptera, III. Can. Entomol. 65: 155-158.
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Ameletus velox Dodds
Type Locale: Colorado
California Distribution: Los Angeles, Nevada, Placer, Riverside, San Bernardino, Santa Clara, Siskiyou, Tulare
Adult Description: Adults were first described by Dodds (1923), who provided a figure of the male genitalia (Fig. 17). Zloty (1996) and Zloty and Pritchard (1997) subsequently included this species in their keys to adult Ameletus.
Larval Description: Dodds (1923) provided a figure of the hypopharynx (Fig. 16), but Zloty and Pritchard provided the only useful description and figures in their key to the Alberta mayflies. They also included a figure of the dorsal coloration (Fig. 20c). Allen and Chao also described a larvae they called A. velox, but this was really the larvae of A. doddsianus (see Zloty and Pritchard 1997).
Identification Notes: Stick with the key in Zloty and Pritchard (1997) as many older descriptions of A. velox actually pertain to other species of Ameletus (see Zloty and Pritchard 1997 for more detail). Although not indicated in the key (Zloty and Pritchard 1997), I have noticed the antennae to be pale in color but with brown middle segments.
References:
Allen, R. K, and E. S.M. Chao. 1981. Mayflies of the southwest: new records and notes of the Siphlonuridae (Ephemeroptera). Pan-Pacific Entomol. 57: 449-456.
Dodds, G. S. 1923. Mayflies from Colorado, Descriptions of certain species and notes on others. Trans. Amer. Entomol. Soc. 59:93-114.
Ameletus vernalis McDunnough
Type Locale: British Columbia
California Distribution: Alameda, Butte, Lake, Napa, Santa Clara, Shasta, Tulare
Adult Description: McDunnough (1924) originally described this species. Zloty (1996) subsequently included this species in his key of western North America Ameletus. His figure of the genitalia (Fig. 31) is the best one to use to distinguish this species from similar species (see Diagnosis for this species in Zloty 1999).
Larval Description: The larvae was first described by McDunnough (1936) but that description was improved by Zloty and Pritchard (1997), including a figure of the dorsal color pattern (Fig. 21a).
Identification Notes: In California populations, I have noticed the antennae to be pale with brown middle segments.
References:
McDunnough, J. 1924. New Canadian Ephemeridae with notes, II. Canadian Entomol. 56: 90-98, 113-122, 128-133.
McDunnough, J. 1936. Further notes on the genus Ameletus with descriptions of new species (Ephem.). Canadian Entomol. 68: 207-211
Zloty, J. 1996. A revision of the Nearctic Ameletus mayflies based on adult males, with descriptions of seven new species (Ephemeroptera: Ameletidae). Can. Entomol. 128: 293-346.
Zloty, J. and G. Pritchard. 1997. Larvae and adults of Ameletus mayflies (Ephemeroptera: Ameletidae) from Alberta. Can. Entomol. 129: 251-289