Ostracoda of Moss Town Blue Hole, Great Exuma Island, Great Bahama Bank (Crustacea: Ostracoda: Myodocopa)

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1 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON 121(2): Ostracoda of Moss Town Blue Hole, Great Exuma Island, Great Bahama Bank (Crustacea: Ostracoda: Myodocopa) Louis S. Kornicker*, Thomas M. Iliffe, and Elizabeth Harrison-Nelson (LSK & EHN) MRC 163, Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, D.C., , U.S.A.; (TMI) Department of Marine Biology, Texas A&M University at Galveston, Galveston, Texas, , U.S.A. Abstract. Eight species of myodocopid Ostracoda (six Myodocopina, one Halocypridina, and one Cladocopina) are reported from 30 to 60 m depths in Moss Town Blue Hole, an ocean blue hole located in a bay on the west side of Great Exuma Island, Exuma Cays, Great Bahama Bank. The collection from Moss Town Blue Hole contained no new species, but five species had not been reported previously from the blue holes of Great Exuma Island, and three species had not been reported previously from the blue holes of the Exuma Cays. The collection provided the opportunity to describe the adult male and female, as well as early instars, of Eusarsiella fax and Metapolycope duplex, and the adult female of Eusarsiella merx, and also, to compare the ostracode populations in the various niches in the Exumas. Eight species of myodocopid Ostracoda (six Myodocopina, one Halocypridina, and one Cladocopina) are reported from 30 to 60 m depths in Moss Town Blue Hole, an ocean blue hole located in a bay on the west coast of Great Exuma Island, Exuma Cays, Great Bahama Bank (Fig. 1). Two of the species of Myodocopina, Skogsbergia lerneri (Kornicker, 1958), and Harbansus paucichelatus (Kornicker, 1958) had been reported previously from both Bahamian ocean blue holes and the Bahama platform, and one species of Myodocopina Asteropteron chelisparsa (Kornicker, 1958) had been reported previously from the Bahama platform. Two species of Myodocopina, Eusarsiella merx Kornicker et al., 2002, and E. fax Kornicker et al., 2007, had been reported previously from other ocean blue holes in the Bahamas. The only species of Halocypridina in the * Corresponding author. collection, Deeveya medix Kornicker, 1990, had previously been collected only in inland blue holes in the Bahamas. It is the second species of the genus to be reported from both inland and ocean blue holes in the Bahamas. The only species of Cladocopina in the collection, Metapolycope duplex Kornicker & Iliffe, 1989, had been collected previously only in inland anchialine caves in Bermuda. It is the second benthic myodocopid reported from both the Bahamas and Bermuda, and the first Cladocopina. Early instars of M. duplex have valves with fewer anteroventral serrations than later instars. The adult male and female of Eusarsiella fax and the adult female of E. merx are described for the first time herein. Also described are early instars of E. fax. Station data with specimens collected. Sta , 14 Jan 2003, Moss Town Blue Hole, Great Exuma Island, Exuma Cays, Bahamas; collected with suction bottle, plankton net, and vials (from m

2 238 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Fig. 1. Distribution of inland and ocean blue holes in the vicinity of the Exuma Cays and Great Exuma Island. depths for the plankton tow and 60 m depth for suction bottle and vials); maximum depth reached in the cave was 60 m. Specimens: Asteropteron chelisparsa, 3 juveniles; Deeveya medix, 1 adult male; Eusarsiella fax, 11 specimens; Eusarsiella merx, 1 adult male, 1 adult female, 6 instar I; Harbansus paucichelatus, 2 specimens; Metapolycope duplex, 25 specimens; Skogsbergia lerneri, 7 specimens; Cylindroleberidinae gen. indet., 1 juvenile. Previous work in vicinity of Great Exuma Island. Moss Town Blue Hole lies in a shallow bay at Moss Town on the west side of Great Exuma Island, located on the Great Bahama Bank close to the southwestern end of Exuma Sound. The ostracodes collected in two additional ocean blue holes off Great Exuma Island

3 VOLUME 121, NUMBER have been described: Master Harbor Blue Hole from the east side of the island (Kornicker et al. 2002), and The Subway on the west coast (Kornicker et al. 2007). Several cays are located off the eastern side of Great Exuma Island. The ostracodes collected in ocean blue holes in the vicinity of three of the cays have been described: 1) three blue holes off Stocking Island (Mystery Cave, Angelfish Blue Hole, and Bottomly s Blue Hole); 2) one blue hole off Crab Cay (Crab Cay Crevasse), and 3) one blue hole off Sugar Cay (Sugar Cay Blue Hole) (see Kornicker et al. 2007, table 3). Ostracodes were also reported from a ledge at 8 m depth just outside the cave entrance of Angelfish Blue Hole, which is located on the southwest side of Stocking Island (Kornicker & Iliffe 2000:12). The ostracodes collected in one inland anchialine cave in Great Exuma Island (Basil Minn s Blue Hole) and two inland anchialine caves in two cays making up the string of islands extending northwest from Great Exuma and known as the Exuma Cays: 1) Great Guana Cay (Oven Rock Cave), and 2) Norman s Pond Cay (Norman s Pond Cave) have been described (see Kornicker et al. 2007, table 3). The Great Bahama Bank is dissected by several steep-sided submarine canyons which reach oceanic depths, including Exuma Sound. The upper rim of the southwestern edge of Exuma Sound off Lee Stocking Island, Exuma Cays, is a steep escarpment that bears notches, ledges, and rock overhangs. Myodocopid ostracodes collected on the escarpment off Lee Stocking Island and Georgetown, Great Exuma Island, at depths of m have been reported by Kornicker & Iliffe Discussion. Anchialine inland caves generally are remotely connected to the sea, have minimal water currents and contain organisms usually restricted to caves. In contrast, ocean blue holes are located in or with direct connection to the sea, have strong tidal currents and generally contain organisms also living in the open waters. Some ocean blue holes have been found by cave divers to connect to inland caves, suggesting an environmental and ecological continuum between those two habitat types. In the Bahamas, long, narrow islands such as Great Exuma are located along the margins of large, shallow water platforms called banks. As such, one side of the island faces the shallow bank, while the opposite side borders deep waters of oceanic depths. Tides are delayed on the bank side such that sea levels across the island are consistently out of phase with each other. Ocean blue holes thus serve as tidal conduits with reversing water currents. The walls in such caves are covered with sponges, hydroids and other encrusting marine life, and cave water masses exchange with the sea each tidal cycle. Walls of inland caves are bare in contrast and may be hydrological dead ends, with water remaining within the cave for at least months to years. Moss Town Blue Hole (23u31.969N, 75u50.909W) is situated at the south side of an inland bay connected to the bank side of Great Exuma Island by tidal creeks (Fig. 1). The entrance consists of a circular submerged sinkhole with a steep rubble slope extending down from the surface to 60 m depths where a low but level passageway begins. This passage was only explored for a short distance due to the depth, but appears to continue for some distance. Significant tidal flow moves through the cave, as evidenced by the coarse gravel floor at depth and abundant filter-feeding marine growth. Dives were conducted in the cave at slack tide, and samples taken by stirring or scooping up bottom sediments and filtering water through a 93 mm meshplankton net or by collecting observed animals directly in individual vials. Several other deep blue holes in the vicinity of Moss

4 240 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Town also reach depths approaching 60 m and have significant tidal currents moving through them, suggesting the existence of a complex of deep cave passages in this area. Unfortunately, these other sites have not yet been biologically sampled. The anchialine inland caves in the Bahamas contain ostracodes in the suborders Halocypridina and Cladocopina, but none from the suborder Myodocopina have been reported. The only anchialine inland caves (three grietas) known to contain both an anchialine halocyprid ostracode and a species of Myodocopina are in Santa Cruz Island, Galapagos Islands (Kornicker & Iliffe 1989). The species of Myodocopina there has unusually small eyes suggesting that it may be a stygobiont. Some of the species of Myodocopina in ocean blue holes in the Bahamas are also present in the open sea on the Great Bahama Bank. However, several new species have been described from the ocean blue holes. It is not known at this time whether these also occur in the open sea, but have not been described, or are restricted to ocean blue holes. The species in Exuma s inland and ocean blue holes that were also present on the Exuma Sound escarpment and/or on the shallow waters of the Great Bahama Bank are shown in Table 1. Terminology. Ocean blue holes are openings on the sea floor to extensive, strongly tidal, submerged cave systems. Some oceanic blue holes connect to inland cave systems. For more detailed descriptions of blue holes, see Kornicker & Iliffe (2000:10). Disposition of specimens. All specimens are deposited in the collections of the National Museum of Natural History, Smithsonian Institution, and have been assigned USNM numbers. Symbols and abbreviations. Lowercase letters identify specific bristles (see Poulsen 1962); Roman numerals identify endites; Arabic numbers generally identify article numbers; unlabeled arrows either point to anterior of animal, or draw attention to a feature; stippling in internal shafts generally indicates sclerites; dashed internal shafts indicate muscles; stippling in eyes and upper lip indicate color. The following abbreviations are used in figures and legends: am, adductor muscle; ap, anterior process; av, anterior view; bas, basis; BO, Bellonci Organ; cox, coxa; end, endopod; ep, epipod; esoph, esophagus; ex, exopod; gen, genitalia; iv, inside view; le, lateral eye; lft, left; lv, lateral view; me, medial eye; mnd, mandible; mo, mouth; mv, medial view; mx, maxilla; nabs, not all bristles shown; ov, outside view; precox, precoxa; prot, protopod; rt, right; ul, upper lip; Y-scl, Y-sclerite. Subclass Myodocopa Sars Order Halocyprida Dana Suborder Halocypridina Dana Superfamily Halocypridoidea Dana Family Deeveyidae Kornicker & Iliffe Subfamily Deeveyinae Kornicker & Iliffe Deeveya Kornicker & Iliffe Deeveya medix Kornicker Fig. 2A E Deeveya medix Kornicker in Kornicker et al., 1990:44, figs. 22f, 27, 28, 29f, 30. Kornicker et al., 2007:74, fig. 40. Holotype. USNM , adult male. Type locality. Sagittarius Blue Hole, Sweeting s Cay, Grand Bahama Island, Little Bahama Bank Material examined. Moss Town Blue Hole, Great Exuma Island, Exuma Cays, Great Bahama Bank, Sta : USNM , 1 adult male (body and carapace separated) in 70% ethanol. Distribution. Little Bahama Bank, Sweetings Cay, Grand Bahama Island: Sagittarius Blue Hole and Virgo Blue Hole. Great Bahama Bank, Great Exuma

5 VOLUME 121, NUMBER Table 1. Species collected in Ocean and Inland Blue Holes in the vicinity of Exuma Cays and Great Exuma Island. Localities: ABH, Angelfish Blue Hole on Stocking Island (Stocking Island is 2.2 km NE of Georgetown, Great Exuma Island); BBH, Bottomly s Blue Hole on Stocking Island, part of Mystery Cave system; BMBH, Basil Minn s Blue Hole on Great Exuma Island; CCC, Crab Cay Crevasse on Crab Cay (Crab Cay is 3.6 km SE of Georgetown, Great Exuma Island); MC, Mystery Cave on Stocking Island; MHC, Master Harbor Cave on Great Exuma Island; MTBH, Moss Town Blue Hole on Great Exuma Island; NPC, Norman s Pond Cave on Norman s Pond Cay (Norman s Pond Cay is 49 km NW of Georgetown, Great Exuma Island); ORC, Oven Rock Cave on Great Guana Cay (Great Guana Cay is 78 km NW of Georgetown, Great Exuma Island); SCBH, Sugar Cay Blue Hole on Sugar Cay (Sugar Cay is 700 m N of northern tip of Great Exuma Island); TS, The Subway on Great Exuma Island. Species Ocean Blue Holes Inland Blue Holes SCBH MC BBH ABH CCC TS MHC MTBH ORC NPC BMBH Amboleberis americana** X Asteropteron chelisparsa*/** X Cylindroleberidinae gen. X X indet. Danielopolina exuma X X X Danielopolina kakuki X Danielopolina sp. A X Deeveya exleyi X X Deeveya medix X X Eurypylus hapax** X X Eusarsiella fax X Eusarsiella merx X X Eusarsiella syrinx X Eusarsiella spp. indet. X X X Harbansus paucichelatus** X X X X Junctichela pax X Metapolycope duplex X Pseudophilomedes X ferulanus** Rutiderma darbyi X Skogsbergia lerneri*/** X X X X Spelaeoecia capax X X Spelaeoecia styx X X Synasterope browni*/** X X Synasterope matrix X Synasterope sp. indet. X * Indicates that the species was also collected on the SW escarpment of Exuma Sound. ** Indicates that the species was also present in shallow water on the Great Bahama Bank. Island: Basil Minn s Blue Hole and Moss Town Blue Hole (new locality). Supplemental description of adult male (Fig. 2A E). Carapace ornamentation shown in Fig. 2C. Carapace size (length, height in mm): USNM , right valve 1.62, height with posterodorsal protuberance 1.19, height without posterodorsal protuberance 1.14 (Fig. 2A); left valve 1.62, 1.19 (Fig. 2B). Second antenna: Endopod differs from that described by Kornicker et al. (1990:46) in having a minute medial bristle just ventral to base of 3rd article (Fig. 2D). Copulatory organ: Fig. 2E. Suborder Cladocopina Sars Discussion of anteroventral serrations on valves. Fossils, as well as many species of extant Cladocopina, are known only from valves at an unknown stage of development, and the number of anteroventral serrations on the valves of some

6 242 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Fig. 2. Deeveya medix, adult male, USNM : A, right valve, iv, length 1.62 mm; B, left valve, iv, length 1.62 mm; C, detail of surface structure, right valve just posterior to adductor muscle, ov; D, endopod left second antenna, lv (not under cover slip); E, copulatory organ, lv (drawn on body, not under cover slip; proximal and distal parts separated in illustration). Eusarsiella merx, adult male, USNM : F, left valve on complete specimen, length 0.87 mm, ov; G, right valve on complete specimen (fossae not shown), ov.

7 VOLUME 121, NUMBER Table 2. Comparison of lengths of carapace and number of anteroventral serrations on valves of carapaces of specimens of Metapolycope duplex from Bermuda and the Bahamas. (F 5 female; M 5 male;? 5 sex unknown; nd 5 no data.) Stage** Bermuda* Bahamas Length (mm) Sex Serrations Length (mm) Sex Serrations Instar I 0.25? 4 nd nd nd Instar II nd nd nd nd nd nd Instar III 0.35? ? Instar IV 0.39? ? ? 13 nd nd nd Instar V 0.42 F ? F 15 nd nd nd 0.43 M 17 nd nd nd Instar VI 0.48 F M M 17 nd nd nd Adult 0.54 F F M M M M M M 20 * Data on carapace lengths and number of valve serrations of specimens from Bermuda are from illustrations and figure legends of Kornicker & Iliffe (1989:51 62). ** Stages were identified by appendage morphology, especially by distribution of claws and processes between the claws of the furcal lamellae. specimens has been used to differentiate species. Unless the stage is known, the number of serrations should be used with caution for discriminating species, because in M. duplex, and probably other species, the number of serrations is smaller on early instars (Table 2). Superfamily Polycopoidea Sars Family Polycopidae Sars Subfamily Polycopsisinae Chavtur Metapolycope Kornicker & van Morkhoven Metapolycope duplex Kornicker & Iliffe Figs. 3 6 Polycope spp. Maddocks & Iliffe, 1986: 73 [part]. Metapolycope duplex Kornicker & Iliffe, 1989:50, figs Kornicker et al., 2007, table 12. Holotype. USNM , adult male. Type locality. Bermuda Palm Cave, 13 and 16 Mar Material examined. Moss Town Blue Hole: USNM , adult female on slide and in 70% ethanol; USNM , adult male on slide and in 70% ethanol; USNM A, instar VI male; USNM B, C, 2 adult males; USNM D, instar IV, sex unknown; USNM F, instar V, sex unknown; instar IV, sex unknown; USNM E, instar III, sex unknown; USNM , 17 specimens in 70% ethanol (mostly juveniles). Distribution. Bermuda anchialine caves. Sta , Moss Town Blue Hole, Bahamas. Remarks. This species is the second benthic myodocopid and the first Cladocopina encountered in both Bermuda and the Bahamas. Therefore, an adult male and female from the Bahamas were studied in detail to determine whether the population possessed any morphological characters that could be used to differentiate them from Bermudan males and females. No material differences were

8 244 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Fig. 3. Metapolycope duplex, adult female, USNM : A, specimen from left side, carapace length mm; B, right valve, length mm, iv; C, Bellonci Organ, first and second antennae shown inside left valve (not under cover slip); D, distal left first antenna, lv; E, left second antenna, endopod, lv; F, left mandible, lv; G, precoxa endite of maxilla, coxa endite of mandible, upper lip, all viewed from right side.

9 VOLUME 121, NUMBER observed, except the adult male and female from the Bahamas are slightly smaller than those from Bermuda, and indistinct surface lineations are present on one of the adult males from the Bahamas. To document those observations, illustrations of many appendages of the male and female collected in Moss Town Blue Hole are presented herein. Instars I and II were not present in the collection from Moss Town Blue Hole. Description of adult female from the Bahamas (Figs. 3, 4). Carapace ornamentation: Valve surface smooth; anteroventral margin with serrations. Carapace size (length, height in mm): USNM : 0.489, Central adductor muscle attachments (Fig. 3A, B): Faint, wedge-shaped scars visible. First antenna (Fig. 3C, D): Second antenna (Fig. 3C, E); Mandible (Fig. 3F, G); Maxilla (Figs. 3G, 4A); Fifth limb (Fig. 4B, E G); Furca (Fig. 4C, D); Bellonci Organ (Fig. 3C); Upper lip (Fig. 3G). Description of adult male from the Bahamas (Fig. 5). Carapace ornamentation (Fig. 5A): Anterior outer surface of valves of USNM with lineations; lineations absent on USNM B and USNM C; anteroventral margin of valve with serrations. Carapace size (length, height in mm): USNM : 0.438, (right valve); USNM B: 0.439, 0.400; USNM C, 0.477, First antenna (Fig. 5B D); Second antenna (Fig. 5E); Mandible (Fig. 5F); Furca (Fig. 5G), Posterior of body (Fig. 5G), Copulatory organ (Fig. 5G); Upper lip (Fig. 5H). Description of instar III (sex unknown) from the Bahamas. Carapace ornamentation: Valves with smooth outer surface; anteroventral margin of valve with 12 or 13 serrations. Carapace size (length, height in mm): USNM E, 0.301, Description of instar IV (sex unknown) from the Bahamas. Carapace ornamentation: Valves with smooth outer surface; anteroventral margin of valve with 15 serrations. Carapace size (length, height in mm): USNM D, 0.363, Description of instar V (sex unknown) from the Bahamas. Carapace ornamentation: Valves with smooth outer surface; anteroventral margin with 16 serrations. Carapace size (length only, in mm): USNM F (lost), Description of instar VI male from the Bahamas. Carapace ornamentation: Surface of valves smooth; anteroventral margin of valve with 19 serrations. Carapace size (length, height in mm): USNM A, 0.428, Ontogeny. The numbers of claws and bristles on appendages of instars of the species are presented in Fig. 6. Order Myodocopida Sars Suborder Myodocopina Sars Superfamily Cypridinoidea Baird Family Cypridinidae Baird Subfamily Cypridininae Baird Skogsbergia Kornicker Skogsbergia lerneri (Kornicker) Skogsbergia lerneri (Kornicker, 1958). See Kornicker et al. (2002:34) for comprehensive synonomy. Kornicker et al., 2007:86. Holotype. USNM , whole dry specimen on slide. Type locality. Bimini, Great Bahama Bank. Material examined. Moss Town Blue Hole, Great Exuma Island, Exuma Cays, Great Bahama Bank, Sta : USNM , 7 undissected specimens in 70% ethanol (includes 1 instar I without carapace). Distribution. See Kornicker et al. (2002:34) and Kornicker et al. (2007:86). Herein, Great Bahama Bank, Great

10 246 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Fig. 4. Metapolycope duplex, adult female, USNM : A, right maxilla (not under cover slip), lv; B, right fifth limb (not under cover slip), lv; C, left lamella of furca, lv; D, anterior tip of furca; E, right maxilla (nabs), lv; F, exopod right maxilla, lv; G, right fifth limb (nabs), lv.

11 VOLUME 121, NUMBER Fig. 5. Metapolycope duplex, adult male, USNM : A, specimen from right side, length mm; B, right first antenna, mv; C, distal right first antenna (nabs), mv; D, distal left first antenna (nabs), mv; E, endopod left second antenna, mv; F, right mandible, lv; G, left lamella of furca, copulatory organ, and posterior of body from left side; H, upper lip.

12 248 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Fig. 6. Approximate total number of bristles and claws on each appendage of stages of Metapolycope duplex.

13 VOLUME 121, NUMBER Exuma Island, Exuma Cays, Moss Town Blue Hole (new locality). Superfamily Sarsielloidea Brady & Norman Family Philomedidae Müller Subfamily Pseudophilomedinae Kornicker Harbansus Kornicker Harbansus paucichelatus (Kornicker) Harbansus paucichelatus (Kornicker, 1958). See Kornicker et al. (2002:35) for comprehensive synonomy. Kornicker et al., 2007:87. Holotype. USNM , dried specimen in poor condition. Type locality. Bimini. Great Bahama Bank. Material examined. Moss Town Blue Hole, Great Exuma Island, Exuma Cays, Great Bahama Bank, Sta : USNM , 2 undissected specimens in 70% ethanol. Distribution. See Kornicker et al. (2002:34) and Kornicker et al. (2007:87). Herein, Great Bahama Bank, Great Exuma Island, Exuma Cays, Moss Town Blue Hole (new locality). Family Sarsiellidae Brady & Norman Subfamily Sarsiellinae Brady & Norman Eusarsiella Cohen & Kornicker Eusarsiella styx Kornicker & Iliffe Figs. 7A C, 13H Eusarsiella styx Kornicker & Iliffe, 1989:32, figs Holotype. USNM , ovigerous female in 70% ethanol. Type locality. Cherry Pit Cave, Bermuda. Material examined. Bermuda: Cherry Pit Cave: USNM , paratype, adult male appendages on slide; USNM , paratypes, 5 adult females in 70% ethanol. Distribution. Bermuda [see Kornicker & Iliffe (1989:32) for caves in Bermuda from which specimens were collected.] Discussion. Because of the similarity of specimens of Eusarsiella fax in the present collection and E. styx from Bermuda, types of the latter species were reexamined. Supplementary description of adult female (Holotype, USNM ) (Figs. 7A, 13H). Ornamentation of carapace adequately described by Kornicker & Iliffe (1989:32, fig. 18). Detail of posterior of valve from right side (Figs. 7A, 13H) shows absence of vertical ridge connecting posterior ends of U-shaped rib and, also, presence of outlines of shallow fossae. Supplementary description of adult male (Paratype, USNM ) (Figs. 7B,C). Mandible: Exopod described by Kornicker & Iliffe (1989:39, fig. 22f) as, well developed, about 1/3 length of dorsal margin of first endopodial joint, bifurcate distally with short outer branch; both branches hirsute; inner branch longer, folding over medial surface of joint. Reexamination of the exopod herein revealed indistinct suture on inner branch near base of small outer branch (Fig. 7B,C). Eusarsiella fax Kornicker et al. Figs. 7D H, 14 Eusarsiella fax Kornicker et al., 2007:122, figs Holotype. USNM , A-1 female in 70% ethanol. Type locality. Conch Sound Blue Hole, Andros Island, Great Bahama Bank. Material examined. Moss Town Blue Hole, Great Exuma Island, Exuma Cays, Great Bahama Bank: Sta : USNM , 1 adult female on slide and in 70% ethanol; USNM , 1 adult male on slide and in 70% ethanol; USNM , 1 instar II in 70% ethanol; USNM , 1 instar III in 70%

14 250 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Fig. 7. Eusarsiella styx: A, adult female, holotype, USNM , posterior surface right valve; B, C, adult male, paratype, USNM , exopod of mandible: B, right limb, mv; C, left limb, lv. Eusarsiella fax, adult female, USNM : D, right valve, length 1.17 mm; E, detail from right valve; F, posterior right valve, iv; G, left lateral eye posterior to edge of protopod of left second antenna; H, eggs loose on slide, length of one egg mm.

15 VOLUME 121, NUMBER ethanol; USNM , 1 undissected ovigerous female in 70% ethanol. USNM , 1 undissected instar II in 70% ethanol; USNM , 5 undissected instar IV in 70% ethanol (sex not determined). Distribution. Great Bahama Bank: Andros Island, Conch Sound Blue Hole. Herein, Great Exuma Island, Exuma Cays, Moss Town Blue Hole (new locality). Remarks. Kornicker et al. (2007) described the A-1 (instar IV) female and male of the species. The adult female and male and A-2 (instar III) and A-3 (instar II) instars are described herein. Description of adult female (Figs. 7D H, 8, 9, 13G). Carapace oval in lateral view with triangular fairly short pointed caudal process (Figs. 7D, F, 13G); ventral edge of caudal process slightly convex. Surface with U-shaped rib with posterior ends connected by posterior ridge; posterior ridge with 4 backward-projecting processes (Fig. 7D, E); posterodorsal edge of valve with 4 projecting processes (Figs. 7D, 13G). Ornamentation (Fig. 7D, E): Surface of valve with fossae mostly with irregular outline, but some oval; edge of fossae with inward-pointing minute spines. Minute spines covering valve surface (more apparent along valve edge); spines shorter on ribs. Edge of valve with long bristles with broad bases and shorter slender bristles; each process with long terminal bristle with broad base. Long bristles, some with broad base, sparsely distributed on valve surface. Surface coated with gel-like substance. Infold: Anterior infold with small bristle at midheight. Infold of caudal process with 5 or 6 slender bare bristles (Fig. 7F). Two setal bristles dorsal to caudal process (Fig. 7F). Selvage: Lamellar prolongation with smooth outer edge along valve margins. Prolongation with serrated edge extends well past end of caudal process. Carapace size (mm): USNM , length including caudal process 1.17; height including caudal process USNM , length with or without caudal process 1.19, height First antenna (Fig. 8A): First article bare. Second article with spinous dorsal bristle and few dorsal spines. Third and fourth articles fused; article 3 with 2 bristles (1 ventral, 1 dorsal); article 4 with 3 bristles (2 ventral, 1 dorsal). Article 5 with long ventral bristle with minute filament near midlength. Article 6 with short medial bristle. Article 7: a-bristle short; b-bristle slightly longer than a-bristle; c-bristle slightly shorter than bristle of fifth article, with minute proximal filament. Article 8: d- and e-bristles bare, slightly shorter than bristle of fifth article; f-bristle and g-bristle long with 2 or 3 minute marginal filaments. Second antenna (Fig. 8B, C): Protopod bare. Exopod: First article with small recurved medial spine (Fig. 8C); articles 2 8 with long bristle with proximal ventral spines and distal natatory hairs; bristles of articles 3 6 also with proximal dorsal hairs; ninth article with 2 bristles (dorsal bristle short; ventral bristle shorter than bristle of eighth article, with few proximal slender ventral spines and many distal natatory hairs). Endopod interpreted to be formed of 2 fused articles (Fig. 8B): first article with 2 short bristles; article 2 triangular, bare. Mandible (Fig. 8D, E): Coxa endite consisting of short stout spine; ventral margin of coxa with short spines. Basis: medial surface near ventral margin with 4 short bristles; dorsal margin with 2 short spine-like bristles. Exopod absent. Endopod: article 1 with distal medial spines, row of minute medial spines along distal margin near dorsal edge, 1 or 2 small subterminal dorsal spines, and minute medial bristle near base of stout terminal ventral claw. Article 2 with minute dorsal bristle and stout ventral claw. Article 3 with 2 minute bristles (1 ventral, 1 dorsal)

16 252 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Fig. 8. Eusarsiella fax, adult female, USNM : A, right first antenna, mv; B, endopod, right second antenna, mv; C, proximal articles of exopod of right second antenna, mv; D, left mandible, mv; E, proximal part right mandible, lv; F, left maxilla, lv; G, endite II of left maxilla, lv; H, part right maxilla, mv; I, sixth limb.

17 VOLUME 121, NUMBER Fig. 9. Eusarsiella fax, adult female, USNM : A, fifth limb; B, seventh limb; C, left lamella of furca and posterior of body; D, medial eye and Bellonci Organ, and medial view of proximal part of right first antenna; E, anterior view of upper lip and esophagus; F, left and right genitalia. and stout terminal claw. Minute lateral finger-like process present on distal edge of basis (Fig. 8E) may represent exopod, but not so interpreted herein. Maxilla (Fig. 8F H): Endite I with 6 bristles (Fig. 8H); endite II with 4 bristles (Fig. 8G); endite III with 6 bristles (Fig. 8F). Coxa with short dorsal bristle and lateral row of distal hairs. Basis with short bristle near exopod. Exopod with 2 bristles. Endopod with 2 articles: article 1 with stout alpha- and beta-bristles; article 2 with 2 a-bristles, 1 c-bristle, and 5 pectinate end bristles. Fifth limb (Fig. 9A): Coxa endite with 1 short bristle. Basis with 2 endites: endite I with 2 or 3 bristles; endite II with 3 bristles. Endopod with 2 fused articles: article 1 with 3 bristles; article 2 with 2 bristles. Exopod represented by 1 short bristle. Limb hirsute. Epipod with about 34 bristles. Sixth limb (Fig. 8I): Single endite with 3 small bristles. End article with

18 254 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON 11 bristles plus 2 plumose posterior bristles. Seventh limb (Fig. 9B): Each limb with 2 proximal bristles with 5 bells, and 6 terminal bristles (2 with 4 bells, 4 with 7 bells). Tip with opposing combs, each with 5 or 6 teeth. Each limb with 61 articles plus a terminal article. Furca (Fig. 9C): Each lamella with 5 claws; claw 1 fused to lamella, remaining claws separated from lamella by suture. Claw 1 with stout teeth and smaller teeth between them; claws 2 5 with small teeth. Claw 1 with long medial spines near base. Anterior edges of both lamellae with few minute indistinct spines. Left lamella with few spines along ventral edge following claw 5. Right lamella anterior to left by width of claw 1 at base. Bellonci Organ (Fig. 9D): Elongate with rounded tip. Eyes: Lateral eye with 5 ommatidia; brown pigment between ommatidia (Fig. 7G). Medial eye larger than lateral eye, with brown pigment (Fig. 9D). Genitalia (Fig. 9F): Consisting of 2 oval organs. No bristles observed. Upper lip: Tip with 2 short prongs (Fig. 9E, anterior view of lip compressed under cover slip). Y-Sclerite (Fig. 9C): With ventral branch. Posterior of body: Evenly rounded. Gut content: Unidentified light-amber colored particulate matter. Eggs: USNM with cluster of 5 eggs in marsupium (Fig. 7H) and several unextruded eggs. Diameter of 1 egg in marsupium mm. Description of adult male (Figs A). Carapace with rostrum and fairly short pointed caudal process (Fig. 10A, B); ventral edge of caudal process straight, not slightly convex as on female. Surface with elliptical rib more strongly developed along ventral, dorsal, and posterior parts; anterior part represented by row of bristles similar in length to those on other parts of rib; posterior part with 2 small backward projecting processes; posterodorsal edge of valve with small projecting process. Ornamentation (Fig. 10A): Surface of valve without well-defined fossae with irregular outline present on valve of female. Ribs with small spines. Surface between ribs with spines much shorter than those on ribs and along valve edge. Edge of valve with long and short slender bristles; some long slender bristles with thread-like terminal part. Processes on ribs with long terminal bristle. Long bristles sparsely distributed on valve surface, few with stout proximal part. Surface coated with gel-like substance reaching tips of spines. (Not all surface spines and bristles shown in Fig. 10A.) Infold: Anterior infold with small bristle at midheight. Infold of caudal process with 4 or 5 slender bare bristles (Fig. 10B). Two setal bristles dorsal to caudal process at about midheight of valve. Selvage (not illustrated): Lamellar prolongation with smooth outer edge along valve margins. Prolongation extends past end of caudal process. Carapace size (mm): USNM , length including caudal process 0.92; height First antenna (Fig. 10C, 11I): First article bare. Second article with distal dorsal bristle and distal curved lateral weakly defined line (?incipient suture). Articles 3 and 4 fused; article 3 with 2 bristles (1 ventral short, 1 dorsal longer); article 4 with 3 bristles (2 ventral, 1 dorsal). Article 5 wedged ventrally between articles 4 and 6; stem of sensory bristle with 4 small distal filaments and bifurcate tip (all long basal filaments not shown in Fig. 10C); Article 6 with short medial bristle. Article 7: a-bristle short; b-bristle medial, bare, slightly longer than a-bristle; c-bristle about same length as bristle of fifth article, with 4 marginal filaments. Article 8: lateral d- and e-bristles long, bare, with blunt tips; f-bristle shorter than d- and e-bristles,

19 VOLUME 121, NUMBER Fig. 10. Eusarsiella fax, adult male, USNM : A, complete carapace, length including caudal process 0.92 mm; B, caudal process right valve, iv; C, right first antenna, lv; D, E, endopod left second antenna, mv; F, right mandible, mv; G, exopod right mandible, detail from F; H, copulatory organ from left side.

20 256 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Fig. 11. Eusarsiella fax, adult male, USNM : A, left mandible, mv; B, distal part of maxilla (bristles obscured); C, fifth limb (bristles obscured); D, left sixth limb, lv; E, right seventh limb; F, right lamella of furca and posterior part of left lamella; G, left lateral eye, medial eye and Bellonci Organ; H, right Y-sclerite; I, anterior of body showing right first antenna (nabs), right second antenna (protopod and distal part of endopod), right lateral eye and Bellonci Organ.

21 VOLUME 121, NUMBER with 3 marginal filaments; g-bristles same length as c-bristle, with 5 marginal filaments. Second antenna (Fig. 10D, E, 11I): Protopod bare. Exopod: First article with small recurved medial spine or bristle; bristles of articles 2 8 with long bristle with proximal ventral spines and distal natatory hairs; bristles also with proximal dorsal hairs; ninth article with 2 bristles: dorsal bristle short, with few long marginal hairs; ventral bristle long, with few proximal slender ventral spines and many distal natatory hairs. Endopod with 2 articles (Fig. 10D, E): article 1 with 2 short proximal anterior bristles; article 2 elongate with short subterminal constriction followed by short broad part with 2 ringed terminal bristles. Mandible (Figs. 10F, G, 11A): Coxa endite consisting of short minute indistinct spine; ventral margin of coxa bare. Basis: ventral margin with 2 short proximal bristles; medial surface spinous, with 4 short bristles; dorsal margin with 2 bristles. Exopod about 1/2 length dorsal margin of first endopod article, with 2 articles: proximal article short, cylindrical, bare; second article long, pointed, with long marginal hairs; base of exopod on lateral side of basis. Endopod: first segment with medial spines, few minute medial spines along distal margin near dorsal edge, and 1 or 2 small subterminal dorsal spines; ventral margin with 3 bristles (1 very short). Article 2 with long terminal ventral bristle and dorsal bristle near midlength. Article 3 with 1 minute dorsal bristle, 2 ventral bristles (1 long, 1 minute), and short stout terminal claw with few minute proximal teeth. A stout internal muscle terminates near base of exopod (Fig. 10F). Maxilla (Fig. 11B): Extremely reduced, and details could not be resolved using oil immersion lens. Some indistinct bristles shown in Fig. 11B. Fifth limb (Fig. 11C): Limb reduced and with indistinct bristles difficult to resolve. Coxa endite with 1 short bristle. Basis with 2 endites: endite I with 2 bristles; endite II with about 2 bristles. Endopod with 2 fused articles bearing at least 4 bristles. Exopod represented by 1 short bristle. Limb hirsute. Epipod with about 28 bristles. Sixth limb (Fig. 11D): Single endite with 3 small bristles. End article with 11 bristles plus 2 plumose posterior bristles. Seventh limb (Fig. 11E): Each limb with 4 terminal bristles with 6 or 7 bells. Tip bare. Limb with 54 articles plus terminal article. Furca (Fig. 11F): Each lamella with 5 claws; claw 1 fused to lamella, remaining claws separated from lamella by suture. Claws 1 3 with stout teeth and smaller teeth between them; claws 4 and 5 with small teeth; claw 1 with long medial spines near base. Anterior edges of both lamellae with few minute indistinct spines. Left lamella with few spines along ventral edge following claw 5. Right lamella anterior to left by width of claw 1atbase. Bellonci Organ (Fig. 11G, I): Elongate with rounded tip. Eyes: Lateral eye with 6 or 7 ommatidia and brown pigment between ommatidia (Figs. 10A, 11I). Left lateral eye of USNM unusual in that eye appears to have 3 layers and more ommatidia than eye of female (Fig. 11G). Medial eye about same size as lateral eye, with brown pigment (Fig. 11G). Genitalia (Fig. 10H): Elongate paired organs, each with 3 lobes with bristles; longest lobe terminating in long sclerotized hook. Upper Lip: Tip squarish in anterior view (Fig. 12A, anterior view of lip compressed under cover slip showing relative location of endites of 6th limbs). Y-Sclerite (Fig. 11H): With ventral branch. Posterior of body: Evenly rounded. Gut content: Unidentified light-amber colored particulate matter.

22 258 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Fig. 12. Eusarsiella fax, adult male, USNM : A, upper lip and sixth limb under cover slip, av. Instar II, sex unknown, USNM ; B, complete specimen, length including caudal process 0.70 mm; C, part left first antenna drawn attached to body (nabs), lv; D, protopod and endopod right second antenna, mv; E, sixth limb; F, left seventh limb, lv; G, left lamella of furca and posterior of body showing Y-sclerite; H, anterior of body from right side showing right lateral eye, medial eye and Bellonci Organ; I, left lateral eye; J, anterior of body from right side. Description of instar II (sex unknown) (Fig. 12B J). Carapace in lateral view tapering to pointed caudal process (Fig. 12B). Ornamentation (Fig. 12B): Surface with minute spines and few long bristles. Long bristles with and without broad part near or proximal to midlength numerous along valve margins. Ribs and fossae not apparent. Gel-like substance covering short spines visible along valve margins.

23 VOLUME 121, NUMBER Infold: 1 indistinct bristle on infold of caudal process. Lamellar prolongation well developed along valve edge; prolongation with serrated edge extends well past tip of caudal process. Carapace size (mm): USNM : length including caudal process 0.70, length without caudal process 0.62, height USNM , length including caudal process 0.65, length without caudal process 0.56, height First antenna (Fig. 12C): First article bare. Second article with dorsal bristle. Third and fourth articles fused; third article with 2 bristles (1 ventral, 1 dorsal); fourth article with dorsal bristle. Sensory bristle of long fifth article with small indistinct filament near midlength. Sixth article minute, fused to fifth article, with small medial bristle. Seventh article: a-bristle about twice length of bristle of sixth article; b-bristle shorter than bristle of fifth article; c-bristle slightly longer than bristle of fifth article. Eighth article: d- and e-bristles long bare with blunt tips; f- and g-bristles slightly shorter than c-bristle (g-bristle with short filament proximal to midlength). (b-, c-, f-, and g-bristles may bear marginal filaments not apparent at magnification at which limb examined (403 objective, 15 ocular). Second antenna (Fig. 12D): Protopod bare. Endopod with single article with ventral protuberance (could be interpreted to be 2 fused articles as occurs on adult females), and 1 proximal anterior bristle. Exopod similar to that of adult female. Mandible, maxilla, fifth limb: Not examined in detail but of similar type as that of adult female. Sixth limb (Fig. 12E): With 1 ventral bristle. Seventh limb (Fig. 12F): Short and without bristles. Furca (Fig. 10G): Claw 1 fused to lamella; claws 2 5 separated from lamella by suture; claw 1 with long and short teeth along posterior edge and long medial hairs near base; claws 2 to 4 with short teeth along posterior edges (not all shown). Right lamella with few teeth along anterior edge; left lamella with few spines along edge following claw 5 (not shown). Right lamella anterior to left by width of base of claw 1. Bellonci Organ (Fig. 12H): Elongate with rounded tip. Eyes: Lateral eye with 5 ommatidia and black pigment between ommatidia (Fig. 12H, I). Medial eye larger than lateral eye, with brown pigment forming horizontal zone near midheight (Fig. 12H). Genitalia: Absent. Upper Lip: Rounded in lateral view (Fig. 12J). Y-Sclerite (Fig. 12G): With ventral branch. Posterior of body: Evenly rounded. Gut content: Unidentified light-amber colored particulate matter. Description of instar III,?female (Fig. 13A F). Carapace more ovate than that of instar II (Fig. 13A). Ventral edge of caudal process slightly concave as on adult female. Ornamentation (Fig. 13A): Surface with minute spines and few long bristles. Long bristles with and without broad part near or proximal to midlength numerous along valve margins. Ribs not apparent; small weakly developed process in posterodorsal corner of valve. Fossae very weakly developed. Gel-like substance covering short spines visible along valve margins. Infold: 1 or 2 indistinct bristles on infold of caudal process. Lamellar prolongation well developed along valve edge; prolongation with serrated edge extends well past tip of caudal process. Carapace size: USNM : length including caudal process 0.79 mm, length without caudal process 0.74 mm, height 0.58 mm. First antenna (Fig. 13B): First article bare. Second article with dorsal bristle. Third and fourth articles fused; third article with 2 bristles (1 ventral, 1 dorsal);

24 260 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Fig. 13. Eusarsiella fax, Instar III,?female, USNM : A, carapace from right side, length including caudal process, 0.79 mm; B, part left first antenna (nabs), medial eye and Bellonci Organ, lv; C, endopod left second antenna, mv; D, sixth limb drawn on body (nabs); E, left seventh limb; F, lateral eye. G, adult female, right valve, USNM , ov. H, Eusarsiella styx, adult female, USNM , holotype, right valve, ov. fourth article with 2 bristles (1 ventral, 1 dorsal). Sensory bristle of long fifth article with small indistinct filament near midlength. Sixth article minute, fused to fifth article, with small medial bristle. Seventh and eighth articles with bristles similar to those of adult female, but number of marginal filaments not determined. Second antenna (Fig. 13C): Protopod bare. Endopod and exopod similar to those of adult female. Right limb only of USNM with suture separating first and second articles. Mandible, maxilla, fifth limb: Not examined in detail but of similar type as that of adult female. Epipod of fifth limb with about 26 bristles. Sixth limb (Fig. 13D): With single endite with about 2 small bristles; ventral margin with 8 bristles and 2 posterior bristles. Seventh limb (Fig. 13E): About twice length of limb of Instar II, without bristles. Furca: Similar to that of adult instar II. Bellonci Organ (Fig. 13B): Elongate with rounded tip. Eyes: Lateral eye with 6 ommatidia and black pigment between ommatidia (Fig. 13F). Medial eye only slightly larger than lateral eye, without brown pigment

25 VOLUME 121, NUMBER forming horizontal zone near midheight (Fig. 13B). Genitalia: Absent. Upper lip: Obscured. Y-Sclerite: With ventral branch. Posterior of body: Evenly rounded. Gut content: Unidentified light-amber colored particulate matter. Supplementary description of instar IV (sex undetermined). Carapace size (mm): USNM , 5 specimens: 1, length with caudal process 0.94, length without caudal process 0.84, height 0.73; 2, length with caudal process 0.97, length without caudal process 0.88, height 0.71; 3, length with caudal process 0.93, length without caudal process 0.84, height 0.67; 4, length with caudal process 0.95, length without caudal process 0.86, height 0.68; 5, length with caudal process 0.93, length without caudal process 0.84, height Ontogeny. Carapace: The lateral outline of the female is more ovoid in later stages. Surface ribs are not apparent in instars II and III and are well developed in instar IV and the adult. Surface fossae are very indistinct in instars II and III and the adult male, and well developed in instar IV and the adult female. First antenna: The second article bears 1 dorsal bristle on stages II IV and the adult. The third article bears 2 bristles (1 ventral, 1 dorsal). The fourth article bears 1 ventral bristle on instar II, 2 bristles (1 ventral, 1 dorsal) on instar III, 2 or 3 bristles on instar IV (1 or 2 ventral, 1 dorsal), and 3 bristles (2 ventral, 1 dorsal) on the adult of both sexes. The fifth article of instars II IV bears a ventral sensory bristle; the number of marginal filaments probably increases on later stages. The adult female sensory bristle is of similar type to that of instars, but that of adult male bears a ventral process with abundant filaments, and the fifth article is wedged ventrally between the fourth and sixth articles. The sixth article bears a short medial bristle on all stages; the article is minute in instars II IV and adult female, but is long on adult male. The bristles of the seventh and eighth articles were not examined in detail on all stages, but appear fairly similar. Second antenna: The protopod is bare in all stages examined. The exopod has a similar number of bristles on all stages examined. The endopod of instars II and III (sex unknown) and the adult female have a small bare terminal node, which could be interpreted as a second article. The first article bears 1 ventral bristle on instar II and 2 on instars III and IV and adults of both sexes. The adult male bears an elongate second article with 2 short terminal bristles. Mandible: Instars II and III (sex unknown) of similar type as that of adult female, but not examined in detail. Instar IV (both sexes) similar to that of adult female. Adult male, unlike that of juveniles and adult female, with well developed exopod. Maxilla and fifth limb: Instars II and III of similar type as that of adult female, but not examined in detail. Adult male with much reduced maxilla and 5th limb. Sixth limb: Instar II with only 1 bristle. Instar III adults of both sexes with many bristles. Seventh limb: Instar II with short bare limb. Instar III with longer bare limb. Instar IV with long limb bearing tapered bristles. Adult male and female with cylindrical bristles. Adult female with both proximal and distal bristles and opposing teeth on terminal article. Adult male with only terminal bristles and without terminal teeth. Furca: In general, similar in instars II adults. Bellonci Organ: Similar in instars II adults. Eyes: Lateral eye of instars II IV (sex unknown) and adult female with 5 or 6 ommatidia. Adult male lateral eye may be larger than female eye and have a few more ommatidia. Medial eye about same

26 262 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON for instars II IV (sex of instars II and III unknown) and adults. Discussion. The morphology of the appendages and carapaces of E. fax and E. styx are quite similar, and whether juveniles and adult males of the two species can be separated from their morphology is uncertain. The adult female valve of E. fax bears a continuous posterior vertical rib (Fig. 13G), whereas the rib is discontinuous on E. styx (Fig. 13H). Also, the surface fossae of E. fax are better defined and more irregular in outline than those of E. styx. The third article of the adult female first antenna of E. fax bears 2 bristles compared to only 1 on E. styx. The exopod of the mandible of the adult male E. styx bears a small branch not present on the exopod of E. fax, but more specimens should be examined to ascertain variability. Eusarsiella merx Kornicker et al. Figs. 2F, G, Eusarsiella merx Kornicker et al., 2002:48, figs Holotype. USNM , adult male. Type locality. Sugar Cay Blue Hole, Sugar Cay, Andros Island, Great Bahama Bank. Material examined. Great Exuma Island, Exuma Cays, Moss Town Blue Hole, Great Bahama Bank, Sta , USNM , adult male in 70% ethanol; USNM ; dissected adult female on slide and in 70% ethanol; USNM , 6 undissected 1st instars in 70% ethanol. Distribution. Great Bahama Bank: Andros Island, Sugar Cay, Sugar Cay Blue Hole; Great Exuma Island, Exuma Cays, Moss Town Blue Hole (new locality). Remarks. Kornicker et al. (2002:48 59) described instars I to IV and the adult male. The adult female is described herein. Description of adult female (Figs ). Carapace oval in lateral view with triangular, short, rounded caudal process (Fig. 14A, B, D). Posterodorsal part of each valve with small lateral process. Short low elongate lateral rib present near valve midlength about 1/4 valve height measured from ventral margin. Gel-like coating absent. Ornamentation: Surface of valve with round fossae mostly with minute indistinct inward pointing spines along edge. Smaller brown round spots more abundant than fossae on valve surface; some of these (possibly all) bear short stout spines (Fig. 14C); spines indistinct and some may not terminate in point. Posterodorsal process and lateral rib with long terminal bristle. Edge of valve with long bristles with broad bases and shorter slender bristles. Long bristles sparsely distributed on valve surface. Infold: Infold of caudal process with 7 or 8 slender bare bristles (Fig. 14D). Two bristles dorsal to caudal process (Fig. 14D). Selvage: Lamellar prolongation with smooth outer edge along valve margins. Central adductor muscle attachments (Fig. 14E, F): Indistinct, about 14 oval attachments. Carapace size (mm): USNM , length including caudal process 1.28; height including caudal process First antenna (Fig. 14G): First article bare. Second article with bare dorsal bristle. Third and fourth articles fused; article 3 with 2 bare bristles (1 ventral, 1 dorsal); article 4 with 4 bare bristles (3 ventral, 1 dorsal). Article 5 with long ventral bristle with 1 or 2 minute proximal filaments. Article 6 with short medial bristle. Article 7: a-bristle short; b-bristle twice length of a-bristle; c-bristle slightly shorter than bristle of fifth article, with minute proximal filament. Article 8: d- and e-bristles bare with blunt tips (d-bristle about same length as c-bristle; e-bristle about 2/3 length of d-bristle); f-bristle and g-bristles long.