Annulus Ventralis Research Articles

Changes in secondary sexual characteristics of female red swamp crayfish (Procambarus clarkii) and relationship to ovarian development: Implications for intensive breeding of seedlings

A rapid selection method of mature Procambarus clarkii females for use in intensive breeding of seedlings is proposed based on evaluation of secondary sexual characteristics and variation patterns in this study. Following regular sampling in ponds, the weight, cephalothorax length, annulus ventralis length, body width, white patch coverage (WC) on the uropod, and uropod content weight-to-weight (WW) ratio of female P. clarkii were found to change significantly during ovarian development. The random forest model identified white patches on the uropod as secondary sexual characteristics of female P. clarkii. In fact, the ovarian maturity status could be determined based on the variable pattern of these white patches (distribution shape, coverage, and density), particularly WC. White patches waxed and waned during ovarian development and oviposition. Specifically, white patches were absent from the uropod of female P. clarkii before the avitellogenic stage; visible on the uropod in the early vitellogenic stage (WC < 30%); WC 30–45% occurred in the midvitellogenic stage; WC > 45% occurred in the late vitellogenic stage; and white patches disappeared from the uropod of female P. clarkii in the post-vitellogenic and resorptive stage. The accuracy of identifying mature female P. clarkii (late vitellogenic stage) based on the white patch pattern was 86.36%. Hence, the observation of white patch changes on the uropod might represent an effective method for rapidly identifying mature female P. clarkii with the potential to improve artificial intensive breeding.

Alternation of the female form in Cambaridae (Decapoda: Astacidea) and the designation of a neotype for Procambarus clarkii (Girard, 1852) (Cambaridae: Decapoda)

Abstract The alternation of the female form is examined in eleven species of Cambaridae: Cambarus angularisHobbs &amp; Bouchard, 1994, C. bartonii (Fabricius, 1798), Faxonius virilis (Hagen, 1870), Procambarus alleni (Faxon, 1884), P. clarkii (Girard, 1852), P. fallax (Hagen, 1870), P. pallidus (Hobbs, 1940), Cambarellus leslieiFitzpatrick &amp; Laning, 1976, C. patzcuarensisVillalobos, 1943, C. schmittiHobbs, 1942, and C. shufeldtii (Faxon, 1884). All species show form-alternation in their annulus ventralis, that of Form I showing a cornified sinus and inflated fossa, but the Form-II females show a un-cornificed sinus and deflated fossa. Morphology of the Form-II annulus ventralis is similar to that of a juvenile. A wider abdomen in Form-I females occurred in five species (C. angularis, C. virilis, C. lesliei, C. schmitti, and C. shufeldtii), and inflation of the palm of the cheliped in Form-I females was observed in four (C. angularis, C. bartonii, F. virilis, and P. clarkii). The range of morphometric female-form alternation demonstrates four patterns: 1) wider abdomen and inflated chela (C. angularis, and C. bartonii), 2) wider abdomen and no chela inflation (C. lesliei, C. schmitti, and C. shufeldtii), 3) no wide abdomen and inflated chela (F. virilis and P. clarkii), 4) no wider abdomen and no chela inflation (P. alleni, P. pallidus, and P. fallax,). A neotype of P. clarkii is also designated and described.

Two new species of freshwater crayfish of the genus Faxonius (Decapoda: Cambaridae) from the Ozark Highlands of Arkansas and Missouri

Two new species of freshwater crayfish are described from the Ozarks Plateau of northern Arkansas and southern Missouri. Both species are restricted to the mainstem of rocky streams that are at least fourth-order or greater in size. Recent genetic and morphological investigations of the coldwater crayfish, Faxonius eupunctus Williams, 1952, indicated that it was actually composed of several undescribed species. Faxonius eupunctus is herein restricted to just the Eleven Point River system. Faxonius roberti, new species is found in the mainstem of the Spring and Strawberry river systems in northern Arkansas. It differs from F. eupunctus by lacking a male Form-I gonopod with a distal spatulate mesial process, and presence of two spines on the dorsal side of the merus, where F. eupunctus typically has 1 spine. Faxonius wagneri, new species is known from a 54 mile (86 km) stretch of the Eleven Point River mainstem, ranging from just southeast of Greer, Missouri to just north of Birdell, Arkansas. Faxonius wagneri can be differentiated from both F. eupunctus and Faxonius roberti sp. nov. by using the male Form-I and Form-II gonopods, the shape of the chelae, and the female annulus ventralis. In F. wagneri, the terminal elements of the first pleopod are almost twice as long as those in F. eupunctus and F. roberti, with the tips of the appendage reaching the posterior base of the first perieopod when the abdomen is flexed forward, whereas, in the other two species, these elements only reach the base of the second pereiopod. The species also possesses two spines on the dorsal side of the merus of the first pereiopod, which helps distinguish it from F. eupunctus.

Hybridization between an invasive and a native species of the crayfish genus Orconectes in north-central Ohio

Hybridization between native and invasive species is an important but little-studied factor in crayfish invasions, with few documented natural cases. Here, we report genetic evidence of hybridization between invasive O. rusticus (Girard, 1852) and native O. sanbornii (Girard, 1852) in the Huron River in north-central Ohio based on a combination of molecular markers: nuclear DNA, mitochondrial DNA, and allozymes. Although we found no fixed differences between the species at nuclear DNA loci, fixed differences in mtDNA and allozyme loci confirmed the presence of individuals of hybrid ancestry. We also found preliminary evidence of possible mitochondrial recombination and biparental inheritance (though the existence of rare haplotypes cannot be excluded at the present time). We examined morphological features of both species in sympatry and allopatry and confirmed species-diagnostic morphological features including gonopod traits and shape of the annulus ventralis. This study is the second to detect hybridization between O. rusticus and a congener, which suggests that this may be an important mechanism of invasion by O. rusticus when closely related species are present. Further study of this system, including more extensive sampling and additional molecular markers, is necessary to understand the extent and implications of hybridization for the native species.

Procambarus (Ortmannicus) luxus (Decapoda: Cambaridae), a new crayfish from southern Texas

Procambarus (Ortmannicus) luxus is described from Bee, Brooks, Jim Wells, Kleberg, Nueces, Refugio and San Patricio counties, Texas. It may be distinguished from its nearest relative, P. (O.) texanus, by its strongly asymmetrical first pleopods with proximal extremities separated by a distinct gap; strongly corneous, narrow, scarcely laterally deflected mesial process; slightly more recurved cephalic process and central projection; and an annulus ventralis which is more weakly overhung by the adjacent sternum and bears a prominent caudomedian tonguelike projection.

Four new crayfishes (Decapoda: Cambaridae) of the genus Orconectes from Texas

Four new crayfishes of the genus Orconectes from Texas are described, including Orconectes (Hespericambarus) cyanodigitus, Orconectes (Gremicambarus) castaneus, Orconectes (Buannulifictus) occidentalis and Orconectes (B.) texanus. O. cyanodigitus, of the Red River system, is most closely aligned with O. deanae and O. difficilis. It is distinguished from the former by its gonopod's much shorter, less recurved central projection; and from the latter by its much longer mesial process. O. castaneus, of a small section of the Colorado River system, is most similar to O. nais and O. palmeri longimanus. Its obliterated areola, longer gonopod processes, annulus ventralis structure and color distinguish it from the former; while its shorter gonopod processes, annulus ventralis structure, and color pattern distinguish it from the latter. O. p. longimanus, heretofore considered widely ranging in Texas, is split into three closely allied taxa, with its Texas range reduced to the Red River system and a small tributary of Trinity River; O. texanus occupying most of the remainder of east Texas, including the Sabine, Neches, Trinity, San Jacinto and Navasota basins; and O. occidentalis occupying the Colorado, Guadalupe, Medina, Frio and Nueces systems of central Texas. O. texanus is distinguished from O. p. longimanus by its gonopod's more recurved processes and more strongly tapered central projection, annulus ventralis structure and color pattern; and from O. occidentalis by its annulus ventralis configuration and color pattern. O. occidentalis is distinguished from O. p. longimanus primarily by its annulus ventralis structure and color pattern. Evidence of the extirpation of O. p. longimanus from its type locality is presented.

Conservation of Imperiled Crayfish-Orconectes (Procericambarus) Peruncus (Creaser, 1931) (Decapoda: Cambaridae)

Identification.—The Big Creek crayfish (Fig. 1), Orconectes peruncus, was first described by Creaser (1931) as Cambarus peruncus from Little Creek, a tributary to Big Creek in the St. Francis River drainage, near the town of Chloride, Iron County, Missouri (Fig. 2). This species is a member of the subgenus Procericambarus as defined by Fitzpatrick (1987). The form I male gonopods are long with slender, tapering central projections slightly curved posteriorly and reaching to the bases of the first pereiopods when the pleon is flexed (Creaser, 1931; Pflieger, 1996). The mesial projection of the gonopod is distinctly shorter and thicker than the central projection, and is grooved along its anterior margin, and the apex is widened and recurved (Creaser, 1931; Pflieger, 1996). Form I males possess hooks on the ischia of the third and fourth pereiopods that are reduced in size in form II males. The female’s annulus ventralis possesses an elevated extension on its posterior margin, an irregularly curved sinus, and a wide, shallow fossa (Creaser, 1931; Pflieger, 1996). The crayfish’s base color is described as olive green to tan or brown with many dark spots on the chelae, cephalothorax and pleon, and a prominent blackish saddle stretching laterally across the dorsal surface of the posterior edge of the cephalothorax and anterior edge of the pleon (Creaser, 1931; Pflieger, 1996).

Procambarus (Ortmannicus) hidalgoensis (Crustacea: Decapoda: Cambaridae), a new species of crayfish from Mexico

A new species of crayfish from Camino a Olotla, Tlanchinol County, Hidalgo, Mexico, is described. Procambarus (Ortmannicus) hidalgoensis is most closely related to P. (O.) cuevachicae (Hobbs, 1941) and P. (O.) toltecae Hobbs, 1943, from which it can be distinguished by having a gonopod with a mesial process slightly flattened distally and directed caudodistally; a cephalic process slightly larger than the rest of the terminal elements, originating on the caudal surface; and a plate-like caudal process, exhibiting a strongly folded external part of the pleopod. The annulus ventralis in the new species is rhomboidal, with two strong crests, forming a deep V-shaped depression anteriorly, ending in a sinus in the middle region.

A NEW STYGOBITIC CRAYFISH FROM MEXICO, PROCAMBARUS CAVERNICOLA (DECAPODA: CAMBARIDAE), WITH A REVIEW OF CAVE-DWELLING CRAYFISHES IN MEXICO

Abstract Procambarus (Austrocambarus) cavernicola, a new species of stygobitic crayfish known only from Gabriel Cave, Oaxaca, Mexico, is described. The new species is characterised by a body that lacks pigmentation, except for small purple spots on the eyes; with small setae on the tip of the eye; elongated chelipeds, with the surface of chela covered with small tufts of short setae; first pleopod of form I male with mesial process elongated and conical, triangular central projection, reduced cephalic process and cephalic shoulder forming convex border; annulus ventralis with preannular plate covered with short setae, postannuluar plate oval-shaped, with blunt tubercles. The new species is morphologically similar to other stygobite members of the subgenus Austrocambarus from the Oaxaca–Veracruz area, whose relationships are discussed. The distributions and levels of adaptation to the subterranean environment of 16 cave-inhabiting taxa of Procambarus in Mexico are reviewed.

PHYLOGENY OF FOSSIL AND EXTANT FRESHWATER CRAYFISH AND SOME CLOSELY RELATED NEPHROPID LOBSTERS

The phylogeny of freshwater crayfish is assessed using a morphological analysis of fossil and extant taxa. Based on external morphological characters, primarily characters of the carapace and appendages, the crayfish comprise a monophyletic group (Astacida). The sister taxon to the crayfish is the Chilenophoberidae, a clade of extinct marine lobsters. Synapomorphies of the freshwater crayfish include a distinctive carapace groove pattern and mobility of the last thoracic segment. Within the Astacida, three smaller clades, considered to be family-level groups, are identified and redefined. All parastacid genera except Gramastacus comprise a monophyletic clade. Species in the Cambaridae are characterized by an apomorphous annulus ventralis in the female, and hooks on the ichiopodites on the third pereiopod in the male. Species in the Astacidae are characterized by randomly arranged tubercules on the medial portion of dactyl. The monophyly of the Astacoidea (Cambaridae plus Astacidae) is also supported. The familial affinity of Cambaroides is questioned, and this genus is tentatively reassigned from the Cambaridae to the Astacidae.

A New Stygobitic Crayfish from Mexico, Procambarus Cavernicola (Decapoda: Cambaridae), with a Review of Cave-Dwelling Crayfishes in Mexico

Procambarus (Austrocambarus) cavernicola, a new species of stygobitic crayfish known only from Gabriel Cave, Oaxaca, Mexico, is described. The new species is characterised by a body that lacks pigmentation, except for small purple spots on the eyes; with small setae on the tip of the eye; elongated chelipeds, with the surface of chela covered with small tufts of short setae; first pleopod of form I male with mesial process elongated and conical, triangular central projection, reduced cephalic process and cephalic shoulder forming convex border; annulus ventralis with preannular plate covered with short setae, postannuluar plate oval-shaped, with blunt tubercles. The new species is morphologically similar to other stygobite members of the subgenus Austrocambarus from the Oaxaca–Veracruz area, whose relationships are discussed. The distributions and levels of adaptation to the subterranean environment of 16 cave-inhabiting taxa of Procambarus in Mexico are reviewed.

BEHAVIOR OF JUVENILES OF THE JAPANESE ENDEMIC SPECIES CAMBAROIDES JAPONICUS (DECAPODA: ASTACIDEA: CAMBARIDAE), WITH OBSERVATIONS ON THE POSITION OF THE SPERMATOPHORE ATTACHMENT ON ADULT FEMALES

Abstract The behavior of juveniles of the Japanese endemic crayfish Cambaroides japonicus (Decapoda: Cambaridae) was observed in the field and in the laboratory. In addition, the occurrence and placement of spermatophores on adult females is described from specimens inhabiting small brooks at Otaru and Hamamasu, Hokkaido, Japan, sampled from 1998 to 1999. The second stage juveniles left their mother permanently after some exploration behavior. In adult females, spermatophores were attached to the surface of the seminal receptacle (annulus ventralis), which is situated at the posterior margin of the seventh thoracic sternite. In C. japonicus the invagination of the annulus ventralis is not deep enough to hide the male spermatophores. Previous studies of the Astacidae reported that juveniles left their mother at the second stage, that spermatophores were attached to the surfaces of sternal plates of the last three pereopods, and that an annulus ventralis did not exist. In contrast, Cambaridae juveniles norm...

Aspects of embryonic and postembryonic development of the Japanese freshwater crayfish Cambaroides japonicus (Crustacea, Decapoda) including a hypothesis on the evolution of maternal care in the Astacida

AbstractLittle is known about the biology of the East Asian freshwater crayfish of the genus Cambaroides. Furthermore, the phylogenetic relationships of Cambaroides are controversial. To gain more information about East Asian crayfish and to shed some light on the phylogeny and evolution of freshwater crayfish, some aspects of the embryonic and postembryonic development of the Japanese freshwater crayfish species Cambaroides japonicus are described. The general appearance of the embryo and the growth zone consisting of about 40 ectoteloblasts correspond with the apomorphic pattern described for all other freshwater crayfish species. The occurrence of eight mesoteloblasts is a typical malacostracan character. In addition to the occurrence of freshwater crayfish apomorphies, such as a telson thread, the postembryonic development of C. japonicus follows the ground pattern of the Northern Hemisphere Astacoidea. In particular, some characteristics are in common with the postembryonic development of the Astacidae. These concern the shape of the telson of the juvenile stage 1 and the occurrence of plumose telson setae in juvenile stage 2. Furthermore, the recurved hooks of the hatchlings are lost in the juvenile stage 2, indicating an early independence of the juveniles from the mother. On the other hand, the early appearance of a spermatheca (annulus ventralis) is shared between C. japonicus and the other (American) Cambaridae. The hypothesis is developed that the evolutionary success of the different freshwater crayfish taxa might be related to the stepwise extension of maternal care as an adaptation to the freshwater environment.

ORCONECTES NEGLECTUSIS ESTABLISHED IN THE NORTHEAST

Orconectes neglectus, a crayfish native to the Mississippi River drainage in Arkansas, Oklahoma, Missouri, and Kansas, is reported from streams in southeastern New York for the first time. This species is the newest component of a crayfish fauna that is increasingly dominated by introduced species. Individuals of this species were collected in 1997–1999. First and second form males and females ranged in size from 7.5–40.9 mm carapace length. Ovigerous females were collected in May 1999. These data demonstrate that this species is established and reproducing in clear, rubble-bottom streams in southeastern New York. O. neglectus is readily identifiable by its distinctive coloration and color pattern; other characteristics of the rostrum, mandible, gonopod and annulus ventralis also are useful in distinguishing it from other species inhabiting northeastern North America. Currently, O. neglectus is known in the northeastern United States only from tributaries of the upper Croton River of the lower Hudson River drainage. We assume that it was introduced into the area accidentally.

Morphological variation in fossil crayfish of the Jehol biota, Liaoning Province, China and its texonomic discrimination

Twelve morphological characteristics in 61 fossil crayfish specimens, which came from the Upper Jurassic Yixian Formation, are discussed respectively in the present paper. A study of these new and better preserved materials allows us to add to and revise the original description for Family Cricoidoscelosidae. In our collection, no modifications of the second pleopod of the males have yet been noted. This would be a crucial factor for the diagnosis of the family. Based on the presence of annulus ventralis in bothCricoidoscelosus andPalaeocambarus, they would appear to be very closely allied to those characteristics of the Family Cambaridae. In regard to the family Protastacidae, we seriously doubt it is actually crayfish, in light of the lack of any apomorphies identifiable within the Astacida, and their marine habitat.

Procambarus (Pennides) vioscai paynei, a New Subspecies of Crawfish from East of the Mississippi River (Decapoda, Cambaridae)

-Most of the populations of Procambarus (Pennides) vioscai which occur E of the Mississippi River differ morphologically from the typical forms W of the river. They are here described as a new subspecies, P. vioscai paynei, and are distinguished by unique features of the first pleopod of the Form I male and of the annulus ventralis of the female. The new subspecies is found from the Wolf River drainage of Tennessee in the N to the Tombigbee River drainage in Alabama in the E, and in the S as far as the middle Pearl and upper Pascagoula drainages of Mississippi; in general, it is replaced by other members of the subgenus in drainages leading into Mississippi Sound and the lower Pearl. The zone of intergradation is in the Florida parishes of Louisiana and southwest Mississippi. Some life history data for the two subspecies are presented.

A Revision of the Dwarf Crawfishes (Cambaridae, Cambarellinae)

ABSTRACT Three species-groups of dwarf crawfishes (genus Cambarellus) are accorded subgeneric status: Pandicambarus, containing the most generalized species and restricted to the United States; the monotypic Dirigicambarus, the range of which lies within that of the former; and the nominate subgenus, which is confined to Mexico. Present knowledge of the several character states is such that infrasubgeneric grouping is best attempted by classical rather than cladistic techniques. Tertiary geological data indicate that the Cambarellinae were established in the lower Mississippi River basin prior to the Miocene, reinvading the eastern part of the Gulf Coastal Plain in late Miocene or early Pliocene times. Some descriptive terms to be applied to the annulus ventralis are introduced.

A New Species of Gyretes from Western Florida (Coleoptera; Gyrinidae)

Fig. 1. Mesial view of distal end of first pleopod of first form male. Fig. 2. Lateral view of carapace. Fig. 3. Lateral view of distal end of first pleopod of first form male. Fig. 4. Mesial view of distal end of first pleopod of second form male. Fig. 5. Lateral view of distal end of first pleopod of second form male. Fig. 6. Lateral view of first pleopod of first form male. Fig. 7. Epistome. Fig. 8. Annulus ventralis. Fig. 9. Antennal scale. Fig. 10. Dorsal view of carapace. Fig. 11. Basiopodites and ischiopodites of fourth and third pereiopods of first form male. Fig. 12. Distal three podomeres of first pereiopod of first form male.

STUDIES ON THE SECONDARY SEXUAL CHARACTERS OF CRAYFISHES: X. THE ANNULUS VENTRALIS IN TRUE INTERSEXES OF CAMBARUS

The external secondary sexual characters in the genus Cambarus are so constant in structure and position that they are used extensively for sub-genus and species diagnosis. Some variation has been found in structure, number, and position of these characters, however, in many instances characters of one sex being found on members of the opposite sex. Such variations occur principally in copulatory hooks, oviducal pores, first and second abdominal appendages and, to a lesser extent, in the male genital pores. Variations in the annulus ventralis are extremely rare, records of only four cases being found in the literature. Two additional specimens were recently collected by E. P. Creaser on June 29, 1932. Both specimens were found in one locality, the Huron River, five miles southwest of Dexter, Michigan. These latter two are the only ones seen by the writer in examining more than 75,000 females of the genus Cambarus.