Notes on Indiana crayfish (Decapoda: Cambaridae) with comments on distribution, taxonomy, life history, and habitat.

ABSTRACT. Large collections of crayfish made throughout Indiana during the past several years have increased our knowledge of various aspects of the biology of Indiana's crayfish fauna, including Orconectes (F.) indianensis, a species that had conservation status. New information on distribution, taxonomy, life history, or habitat is provided for Orconectes (Faxonius) indianensis, Orconectes (Trisellescens) immunis, Orconectes (Crockerinus) propinquus, Orconectes (Procericambarus) rusticus, Cambarus (Tubericambarus) sp. "A," Cambarus (Erebicambarus) tenebrosus, Cambarus (Erebicambarus) laevis, Procambarus (Ortmannicus) acutus and P. (Scapulicambarus) clarkii. Reproductive biology, fecundity, egg diameter size, and instar lengths are provided for Orconectes (F.) indianensis, Orconectes (T.) immunis, Orconectes (C.) propinquus, Cambarus (T.) sp. "A," and Procambarus (S.) clarkii, including chronology of appearance on the female abdomen. The largest ova diameters belong to Cambarus (T.) sp. "A" and Procambarus (S.) clarkii with diameters between 2.1-2.5 mm, while Orconectes (T.) immunis had the smallest ova ranging between 1.4-2.0 mm.

Keywords: Distribution, taxonomy, life history, habitat

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Hobbs (1989), less than 20 years ago, indicated that 17 species of crayfish were known to occur in Indiana. Our knowledge of the biology and zoogeography of Indiana species is limited to mostly those species occurring in the northern portions of the state; however, the species composition of the southern portions of the state has been clouded by taxonomic and ecological uncertainties. Since the publication of the Hobbs list, Page & Mottesi (1995) and Simon (2001) have presented checklists of the crayfish fauna of Indiana, adding several species previously unknown to occur in the state, and have reported on the recommended conservation status. Simon & Thoma (unpubl. data) and Simon (2002) expanded the range of another introduced crayfish, while Taylor (2000) described a new species that ranges into the state. Further investigation and field surveys have discovered additional new species (Simon unpubl. data).

Several hundred collections made during the past several years have added significantly to our understanding of the biology of many Indiana crayfish, including several species that have limited ranges or the greatest parts of their ranges within the State. This paper provides new distribution, taxonomic, and habitat data for nine species that occur in Indiana, and reproductive information on five of these species.

METHODS

Crayfish carapace length (CL) was measured from the anterior tip of the rostrum to the posterior margin of the areola using digital calipers that measured to the nearest 0.1 mm. Ova diameters and instar lengths were measured using an optical micrometer inserted in a Bausch and Lomb Stereozoom 7 microscope. All ova and instars were measured to the nearest 0.01 min. All crayfish were collected legally, with permission from the appropriate state government agencies. Life history and distribution information is based on new observations from referenced Indiana collections. We do not repeat previously published distribution information published in Simon & Thoma (2003) and Thoma et al. (in press); however, information presented on significant reproductive biology information is based on material from the Patoka River collections which is included for the reader's benefit.

The following abbreviations are used in the text: INBS = Indiana Biological Survey, Crustacean Collection, Bloomington; US = United States highway; SR = Indiana state highway; CR = Indiana secondary (county) road; d/s = downstream; lat = latitude; lon = longitude. Names of collectors are provided in first usage, initials thereafter. Specimen abbreviations include PCL = postorbital carapace length, TCL = total carapace length, MI = first form male, MII = second form male, F = female, FE = female with eggs, FOVIG = ovigerous female, juv = juvenile, and P = partial specimen (usually a chelae). Catalogue numbers are those of voucher specimens in the INBS Crustacean Collection unless otherwise noted.

RESULTS AND DISCUSSION

Orconectes (Faxonius) indianensis (Hay) Indiana Crayfish

The Indiana crayfish Orconectes (F.) indianensis is a state Species of Special Concern and was considered a federal candidate species until the release of a conservation status report published by Page (1994). Simon (2001) recommended that the state list the Species as Special Concern because of its apparent rarity until further studies could be completed.

Distribution.--Page & Mottesi (1995) determined that O. (F.) indianensis did not warrant conservation status because the species had been found at 10 locations in Indiana. The majority of these sites were in the Patoka River drainage, an area that is threatened from oil and gas exploration and coal extraction (Simon et al. 1995; Simon et al. 2005). The species presence was investigated in the Patoka River drainage to determine whether additional occupied locations existed (Simon & Thoma 2003). Simon & Thoma (unpubl. data) evaluated the conservation status of the species in the Patoka River drainage and found that it was much more common than previously known.

The species was collected from the following additional locations: PATOKA RIVER DRAINAGE: Dubois County: Little Flat Creek, CR 300 W bridge, 2 mi SE Otwell, Madison Twp., lat 38.4225 N, lon 87.0687 W, 11 April 2001,, 4 FE, 4 FOVIG, l0 MI, l0 MII, (Thomas P. Simon). Mill Creek, CR 600 N bridge, 1.5 mi SW Haysville, Boone Twp., lat 38.4672 N, lon 86.7563 W, 11 April 2001, 4 FE, 1 MI, 1 MII, 2 juv, (TPS). Davis Creek, Cuzco Road bridge, Crystal, Columbia Twp., lat 38.4878 N, lon 86.7563 W, 19 May 2001, 2 FOVIG, 25 MI, 18 MII, (TPS, Roger F. Thoma & Foster Purrington). Orange County: Cane Creek, CR 500 S bridge, 4.5 mi S French Lick, Jackson Twp., lat 38.4790 N, Ion 86.6588 W, 19 May 2001, 47 FE, 2 FOVIG, 59 MII, (TPS, RFT & FP). Unnamed tributary Patoka River, CR 825 S bridge, Valeen, Southeast Twp., lat 38.4342 lon 86.3975 W, 21 May 2001, 1 FE, 1 FOVIG, (TPS, RFT & FP).

Life history.--Limited information is available on the reproductive biology of O. (F.) indianensis. The species is lithophilic, requiring minimal amounts of rock, and usually associated with the areas beneath bridges (Simon & Thoma unpubl, data). The earliest date in 2001 that a female was found carrying ova was mid-April, while the latest that instars were observed was late May (Table 1). Page (1985) reported females carrying ova during March and April and young only during May. Ova ranged from 1.2-1.8 mm diameter (Table 1). First form males were collected in Indiana during April, July, and October, while Page (1985) indicated that first form males were present in Illinois during March, August, September, and October.

Orconectes (Trisellescens) immunis (Hagen) Calico Crayfish

Distribution.--Orconectes (G.) immunis has one of the widest geographical ranges, occurring from Maine and Connecticut to eastern Colorado and Wyoming, and from Alabama to southern Manitoba, Ontario, and Quebec (Hobbs 1989). The distribution of the species in Indiana has not been completely surveyed; however, it occurs statewide with perhaps the greatest abundance in southwestern Indiana.

Life history.--Despite the thousands of specimens residing in research collections, limited life history information is available for the species in Indiana. Life history information has been reported for northern populations from Ontario (Crocker & Barr 1968), Wisconsin (Hobbs & Jass 1988), and Illinois (Page 1985). Detailed life histories for this species have been done by Tack (1941) and Caldwell & Bovbjerg (1964).

First form males were collected from southern Indiana during April, May, July, and August. The earliest ovigerous female found was during early April in the South Fork Patoka River, CR 300 E bridge, 1.5 mi SE Coe, Monroe Twp., lat 38.2872 N, lon 87.2193 W, 4 April 2001, (TPS) (Table 1). Ova ranged in diameter from 1.0-2.0 mm. Juvenile crayfish were collected in mid-May and July.

Orconectes (Crockerinus) propinquus (Girard) Northern Clearwater Crayfish

Distribution.--Our data are based on these specimens: EAST FORK WHITE RIVER DRAINAGE: Monroe County: Jordan River, 1.5 mi E Bloomington, Bloomington Twp., lat. 39.16648 lon 86.52454, (TPS). Jackson Creek, d/s Rogers Road, 2.75 mi SE Bloomington, Perry Twp., 16-18 June 2002, lat 39.13656 N, lon 86.50660 W, (TPS & Cameron C. Simon). Bean Blossom Creek, Currie Pike Rd, 7 mi N Bloomington, Bloomington Twp., 26 June 2001, lat 39.2377 N, lon 86.5275 W, (TPS).

Life history.--Most life history information for Orconectes (C.) propinquus is based on data from Ontario, Wisconsin, and limited data from Illinois (Crocker & Barr 1968; Hobbs & Jass 1988; Page 1985). Life history data from the southern portions of the range in Indiana are lacking. First form males from the above sites in southern Indiana were collected during April, July, August, and October. Females carried ova from mid-June until late August (Table 1). Ova ranged from 2.0-2.2 mm diameter.

Orconectes (Procericambarus) rusticus (Girard) Rusty Crayfish 

Distribution.--The native range of Orconectes (P.) rusticus in Indiana includes the Whitewater, Greater Miami, and Maumee river drainages (Hay 1896). The transport and spread of this species through bait-bucket transfer of adults has had devasting effects on the aquatic assemblages of northern Wisconsin lakes (Lodge et al. 1986; Lodge et al. 1994). Taylor & Redmer (1996) reported on the spread of Orconectes rusticus in Illinois, but no information exists for the status of the species in Indiana. Specimens obtained from the Bureau of Water Quality, City of Muncie, from surveys during the early 1970s document the species as common in the upper West Fork White River from multiple locations near Muncie (Simon unpubl, data). Surveys in the West Fork of the White River found the species to be dominant in tributaries extending from the Ohio state line west to Indianapolis and in the upper East Fork and major tributaries (Simon unpubl, data). Taylor & Redmer (1996) documented the spread of O. rusticus in Illinois. A similar study has not been completed in Indiana so exact distribution of the species is unknown. A life history study is also being conducted in the Little Mississinewa River, Randolph County.

Cambarus (Tubericambarus) sp. "A" Painted-hand Mudbug 

Taxonomy.--Jezerinac (1993) created the subgenus Tubericambarus and indicated that there were multiple undescribed species within the Cambarus diogenes complex. The species assigned as Cambarus (T.) sp. "A" by Jezerinac (1993) is currently being described (Thoma et al. in press). This species is distributed from southeastern Michigan south to Tennessee, and from western Pennsylvania to eastern Missouri.

Distribution.--The type locality is PATOKA RIVER DRAINAGE: Pike County: Flat Creek, CR 124 S bridge, Washington Twp., lat 38.4019 N, lon 87.3066 W, 24 March 2001, 4 MI, 3 MII, 8 F (TPS, RFT & FP). Thoma et al. (in press) provides thorough distribution information for this species. Further research on the Cambarus diogenes complex will result in the recognition of other species from Indiana, and possibly another six species throughout that species' former range.

Life history.--First form males were collected from southern Indiana in 2001 during March, April, and May. Females were first found carrying ova in early April, and instars were last collected in mid-June (Table 1). Juveniles were collected in mid-May.

Cambarus (Erebicambarus) laevis Faxon Karst Crayfish

Taxonomy.--Taylor (1997) synonomized Cambarus (E.) laevis with Cambarus (E.) tenebrosus based on morphological characters and found fewer differences among sites than within sites. However, based on our observations, several key morphological differences were observed among Indiana populations of these two forms. We observed preliminary differences in first form male gonopod structure, branchiostegal tubercle presence, chelae shape, size of first form males, and pigmentation (Simon unpubl. data).

Distribution.--Cambarus (E.) laevis is a wide-ranging species found throughout central and southern Indiana, but few published records exist for the species outside of Monroe County. The following collections, all represented by voucher specimens, establish the presence of Cambarus (E.) tenebrosus into southern Indiana: EAST FORK WHITE RIVER: Monroe County: Unnamed tributary, Birdie Galien Road, 8.5 mi E Bloomington, Salt Creek Twp., lat 39.15301 N, lon 86.38444 W, 18 December 1998, 1 F, (TPS, TPS IV, CCS). PATOKA RIVER DRAINAGE: Pike County: Unnamed tributary Patoka River, SR 364 bridge, 1.5 mi SE Winslow, Marion Twp., lat. 38.3558 N, lon 87.16683 W, 18 May 2001, 1 F, 2 P (TPS). Dubois County: Mill Creek, CR 600 N bridge, 1.5 mi SW Haysville, Boone Twp., lat 38.46717 N, lon 86.94717 W, 27 March 2001, 1 F (TPS). Orange County: Cane Creek, CR 500 S bridge, 4.5 mi S French Lick, Jackson Twp., lat 38.4790 N, lon 86.65883 W, 11 May 2001, 1 F, 3 MII, 2 juv, (TPS, RFT & FP). Cane Creek, Cuzco Road, S Cuzco, Columbia Twp., lat. 38.4705 N, lon 86.7220, l F (TPS, RFT & FP). Young's Creek, CR 600 S bridge, Hoosier National Forest, Greenfield Twp., lat. 38.51583 N, lon. 86.51567 W, 11 April 2001, 1 F, 1 MI, 1 MII, 2 juv, (TPS, RFT & FP). Unnamed tributary Patoka River, CR 825 S bridge, Valeen, Southeast Twp., lat 38.434167 N, lon 86.3975 W, 21 May 2001, 1 F, (TPS, RFT & FP). Patoka River, CR 500 E bridge, 2 mi SSE Chambersburg, Stampers Creek Twp., lat 38.48433 N, lon 86.37367 W, 7 June 2001, 1 F, (TPS).

Life history.--The karst crayfish Cambarus (E.) laevis is generally found in small brooks, creeks, and streams beneath large flat stones. These stones can be distributed throughout the width of the stream, but generally are found along the edges of the stream in the greatest current. First form males from the Patoka River drainage were collected in May.

Carnbarus (Erebicambarus) tenebrosus Hay Cavespring Crayfish

Taxonomy.--We recognize Taylor's (1997) recommendation to synonomize Cambarus (E.) laevis with Cambarus (E.) tenebrosus, but we have chosen to keep these two forms separate until further cladistic and genetic analysis can be accomplished since we observed several differences, which might prove that the species are distinct.

Distribution.--Cambarus (E.) tenebrosus occurs in southern Indiana along the edge of the Wisconsian glacial advance south into karst areas. Distribution of the species occurring primarily throughout Monroe County and further south has not been well-documented. Our new records include: PATOKA RIVER DRAINAGE: Orange County: Unnamed tributary Patoka River, Spring Spring's cave outlet, CR 475, Stumpers Creek Twp., lat 38.48966 N, lon 86.36317 W, 21 May 2001, 1 FE, 1 MI, 1 MII, (TPS, RFT & FP).

Life history.--The cavespring crayfish is generally found within caves near the outlet of small to moderate-sized streams beneath large flat stones with non-imbedded cobble substrates. Large adults are generally found beneath the largest slab stones along either the edge or in the center of the stream. First form males were collected during December.

Procambarus (Ortmannicus) acutus (Girard) White River Crayfish

Distribution.--Procambarus (O.) acutus is widespread and abundant in the Coastal Plain and the Piedmont Plateau of North Carolina (Cooper 2002), but is limited to lowland streams in Indiana. The following are new vouchered records for the species: PATOKA RIVER DRAINAGE: Pike County: Unnamed tributary Cup Creek, unnamed CR, 0.75 mi NW Pikeville, Lockhart Twp., lat 38.32733 N, lon 87.12893 W, 26 March 2001, 1 F, (TPS, RFT & FP). Dubois County: Indian Creek, SR 64 bridge, lat 38.299333 N, Ion 86.91533 W, 18 May 2001, 1 F,(TPS, RFT & FP). Short Creek, Sunset Road, 1.5 mi SE Huntingburg, Ferdinand Twp., lat. 38.2743 N, lon. 86.9322 W, 18 May 2001, 1 F, (TPS, RFT & FP).

Life history.--We have collected this species from the West Fork White River drainage in intermittent and perennial headwater streams. The species is more common in southwestern Indiana, occurring in wetlands, small vernal ponds, and stream habitats (Simon unpubl. data).

Procambarus (Scapulicambarus) clarkii (Girard)

Louisiana Red Swamp Crayfish

Distribution.--Page (1985) indicated that Procambarus (S.) clarkii was limited to the Coastal Plain lowlands of Illinois and that the species was rare in Indiana. Simon & Thoma (unpubl. data) found the species along the southern shore of Lake Michigan in drowned river mouth coastal wetlands. The species has since been found in additional locations including: LAKE MICHIGAN DRAINAGE: Lake County: East Branch Grand Calumet River, d/s Kennedy Avenue, East Chicago, Lake Twp., 18 November 1999, 1 FOVIG, (TPS & James R. Smith). West Branch of the Grand Calumet River, d/s Indianapolis Boulevard, East Chicago, Lake Twp., 2 December 1999, lat 41.61430 N, 8747975 W, 3 FOVIG, 1 MI, (TPS & Alex Peine).

Life history.--Ovigerous females collected from the West Branch of the Grand Calumet River and from Illinois, Lake County, Dead River mouth in Illinois Beach State Park included females with 1st instar and ova with eyespots on the verge of eclosion (Table 1). First form males were collected in July, September, November, and December from Indiana and Illinois populations. Ovigerous females had ova that ranged from 2.0-2.5 mm diameter (Table 1).

ACKNOWLEDGMENTS

We appreciate the specimens provided by many colleagues. Without their diligent efforts and well-documented voucher specimens we would not be as knowledgeable about the distribution and biology of these species. Special thanks to Anthony Brannam, Natural Resource Conservation Service; Brant E. Fisher, Indiana Department of Natural Resources; Stacy Sobat, Indiana Department of Environmental Management; and Dale Sparks, Indiana State University, all of whom provided crustaceans during the course of their own various field surveys.

Manuscript received 16 March 2005, revised 19 May 2005.

LITERATURE CITED

Caldwell, M.J. & R.V. Bovbjerg. 1964. Natural history of the two crayfish of northwestern Iowa, Orconectes virilis and Orconectes immunis. Iowa Academy of Science Proceedings 76:463-472.

Cooper, J.E. 2002. North Carolina crayfishes (Decapoda: Cambaridae): Notes on distribution, taxonomy, life history, and habitat. Journal of the North Carolina Academy of Science 118:167-180.

Crocker, D.W. & D.W. Barr. 1968. Handbook of the Crayfishes of Ontario. Royal Ontario Museum, University of Toronto Press, Toronto.

Hay, W.P. 1896. The crawfishes of the state of Indiana. Pp. 475-507, In 20th Annual Report of the Department of Geology and Natural Resources of Indiana.

Hobbs, H.H., Jr. 1989. An illustrated checklist of the American crayfishes (Decapoda: Astacidae, Cambaridae, and Parastacidae). Smithsonian Contributions in Zoology 480: 1-236.

Hobbs, H.H., III & J.P. Jass. 1988. The Wisconsin Decapod Crustaceans (Cambaridae, Palaemonidae). Contributions of the Milwaukee Public Museum, viii + 177 pp.

Jezerinac, R.F. 1993. A new subgenus and species of crayfish (Decapoda: Cambaridae) of the genus Cambarus, with an amended description of the subgenus Lacunicambarus. Proceedings of the Biological Society of Washington 106:532-544.

Lodge, D.M., T.K. Kratz & G.M. Capelli. 1986. Long-term dynamics of three crayfish species in Trout Lake, Wisconsin. Canadian Journal of Fisheries and Aquatic Sciences 43:993-998.

Lodge, D.M., M.W. Kershner, J.E. Aloi & A.P. Covich. 1994. Effects of an omnivorous crayfish (Orconectes rusticus) on a freshwater littoral food web. Ecology 75:1265-1281.

Page, L.M. 1985. The crayfishes and shrimps (Decapoda) of Illinois. Illinois Natural History Survey Bulletin 4:335-448.

Page, L.M. 1994. The distribution and status of the Indiana crayfish, Orconectes indianensis. Illinois Natural History Survey, Champaign. Center for Biodiversity, Technical Report 1994(2).

Page, L.M. & G.B. Mottesi. 1995. The distribution and status of the Indiana crayfish, Orconectes indianensis, with comments on the crayfishes of Indiana. Proceedings of the Indiana Academy of Science 104:103-111.

Simon, T.P. 2001. Checklist of the crayfish and freshwater shrimp (Decapoda) of Indiana. Proceedings of the Indiana Academy of Science 110:104-110.

Simon, T.P. 2002. North American crayfish: Introductions from bait bucket and the aquarium trade. Lakeline 22:52-54.

Simon, T.P., R.L. Dufour & B.E. Fisher. 2005. Changes in the biological integrity of fish communities in the Patoka River as a result of anthropogenic disturbance from 1888 to 2001. Pp. 245-261, In Historical Changes in Large River Fish Assemblages of the Americas. (J.N. Rinne, R.M. Hughes & B. Calamusso, eds.). American Fisheries Society, Bethesda, Maryland.

Simon, T.P., S.A. Sobiech, T.H. Cervone & N.E. Morales. 1995. Historical and present distribution of fishes in the Patoka River basin: Pike, Gibson, and Dubois counties, Indiana. Proceedings of the Indiana Academy of Science 104: 193-206.

Simon, T.P. & R.F. Thoma. 2003. Distribution patterns of freshwater shrimp and crayfish (Decapoda: Cambaridae) in the Patoka River basin of Indiana. Proceedings of the Indiana Academy of Science 112:175-185.

Tack, P.I. 1941. The life history and ecology of the crayfish, Cambarus immunis Hagen. American Midland Naturalist 25:420-446.

Taylor, C.A. 1997. Taxonomic status of members of the subgenus Erebicambarus, genus Cambarus (Decapoda: Cambaridae), east of the Mississippi River. Journal of Crustacean Biology 17: 352-360.

Taylor, C.A. 2000. Systematic studies of the Orconectes juvenalis complex (Decapoda: Camharidae), with descriptions of two new species. Journal of Crustacean Biology 20:132-152.

Taylor, C.A. & M. Redmer. 1996. Dispersal of the crayfish Orconectes rusticus in Illinois, with notes on species displacement and habitat preference. Journal of Crustacean Biology 16:547-551.

Thoma, R.F., R.F. Jezernac & T.P. Simon. in press. Cambarus (Tubericambarus) polychromatus (Decapoda: Cambaridae), a new species of crayfish from the midwestern United States. Proceedings of the Biological Society of Washington.

Thomas P. Simon, Matthew Weisheit, Elizabeth Seabrook, Lori Freeman, Scott Johnson, Lynn Englum, Katherine W. Jorck, Matthew Abernathy and Thomas P. Simon IV: Aquatic Research Center, Indiana Biological Survey, 6440 Fairfax Road, Bloomington, Indiana 47401 USA

Table 1.--Reproduction biology of select crayfish species including
information on chronology of appearance, ova size, and instar
development. Columns include Indiana Biological Survey (INBS)
Crustacean Collection number, postorbital carapace length (PCL),
date of collection, number, and condition (ova and instar size and
number).

Collection   PCL
number       (mm)   Date

Orconectes (F.) indianensis
    93        22    11 April 2001
              25
              21
              22
    79        23    11 April 2001
    83        19    19 May 2001
    51        14
   200        21    19 May 2001
              17
   193        20    21 May 2001

Orconectes (T.) immunis
    67        30    4 April 2001
   128        21    5 April 2001
   141        22    5 April 2001
              27
    70        23    5 April 2001
              25
    73        32    5 April 2001
   160        18    10 April 2001
   178        13    11 April 2001
    87        21    11 April 2001
    87        26
    87        26
   126        25    11 April 2001
   136        22    11 April 2001
   136        23
   162        24    11 April 2001
   136        27
    56        23    11 April 2001

Orconectes (C.) propinquus
   215        25    16 June 2001
   219        25    2 August 2001
   222        20    21 August 2001

Cambarus (T.) sp. "A"
    67        29    4 April 2001
    67        34
   163        47    23 March 2001
    64        35    21 May 2001

   224        42    16 June 2001

Procambarus (S.) clarkii
   226        34    8 July 2000
   227        37    21 September 2002

Collection   PCL
number       (mm)   Condition

Orconectes (F.) indianensis
    93        22    155 1st instar young, ca. 3-4 mm PCL (rostrum
                      undeveloped);
              25    205 1st instar young, ca. 3-4 mm PCL (rostrum
                      undeveloped)
              21    101 ova with eyespots on verge of eclosion, ca.
                      1.5-mm diameter
              22    159 ova, 1.2-1.8 mm diameter
    79        23    209 ova, 1.5-1.7 mm diameter
    83        19    16 1st instars, ca. 3-4 mm PCL (rostrum
                      undeveloped)
    51        14    23 1st instars, ca. 3-4 mm PCL (rostrum
                      undeveloped)
   200        21    20 1st instars, ca. 3-4 mm PCL (rostrum
                      undeveloped)
              17    17 1st instars, ca. 3-4 mm PCL (rostrum
                      undeveloped)
   193        20    108 1st instars, ca. 4 mm PCL

Orconectes (T.) immunis
    67        30    367 ova, 1.7-2.0 mm diameter
   128        21    194 ova, 1.0-1.5 mm diameter
   141        22    194 ova, 1.5-2.0 mm diameter
              27    237 ova, 1.4-2.1 mm diameter
    70        23    204 ova, 1.2-1.8 mm diameter
              25    229 ova, 1.6-1.8 mm diameter
    73        32    191 ova, 1.9-2.1 mm diameter
   160        18    104 ova, 1.4-2.0 mm diameter
   178        13    33 ova, 1.2-1.5 mm diameter
    87        21    185 ova, 1.5-1.7 mm diameter
    87        26    372 ova, 1.5-1.8 mm diameter
    87        26    68 ova, 1.1-2.0 mm diameter
   126        25    333 1st instar young, ca. 3 mm PCL (rostrum
                      undeveloped); 1 ova with eyespots on verge of
                      eclosion, ca. 1.8 mm diameter
   136        22    90 ova, 1.5-1.8 mm diameter
   136        23    184 ova, 1.7-2.0 mm diameter
   162        24    33 1st instars, ca. 3-4 mm PCL
   136        27    58 1st instars, ca 3-4 mm PCL
    56        23    209 ova, 1.6-2.0 mm diameter

Orconectes (C.) propinquus
   215        25    232 ova, 2.0-2.1 mm diameter
   219        25    34 1st instars, ca. 4 mm PCL
   222        20    5 ova with eyespots on verge of eclosion, ca.
                      2.0-2.2 mm diameter
Cambarus (T.) sp. "A"
    67        29    75 1st instar young, ca. 4 mm PCL (rostrum
                      undeveloped); 1 ova with eyespots on verge of
                      eclosion, ca. 2.4 mm diameter
    67        34    118 1st instar young, ca. 4-5 mm PCL
   163        47    234 ova, 2.1-2.5 mm diameter
    64        35    36 instars, ca. 4-5 mm PCL; 5 ova, 2.1-2.4 mm
                      diameter
   224        42    72 1st instars, ca. 4-5 mm PCL; 36 ova, 2.1-2.5 mm
                      diameter

Procambarus (S.) clarkii
   226        34    198 ova, 2.0-2.5 diameter
   227        37    132 1st instar young, ca. 3-4 mm PCL (rostrum
                      undeveloped); 4 ova with eyespots on verge of
                      eclosion, ca. 2.0-2.4 mm diameter