Caridina fossarum Heller, 1862

Caridina fossarum Heller, 1862 View in CoL

Caridina fossarum Heller, 1862: 411 View in CoL . [Schiraz]

not: Caridina syriaca Bouvier, 1904: 132 . [Syrie]

( Figs. 2 View Fig – 6)

Material examined

Syntypes. 8 ♂♂, 15 ♀♀, 13 ovig. ♀♀, Persien (= Iran), Shiraz, leg. Kotschy, det. Heller 1862, NHW 469 .

Additional material

Iran: 11 ♀♀ cl 4.5 – 6.9 mm, 4 ♂♂ cl 4.6 – 5.3 mm, Fars Province, small streams, leg. P. Malekpouri, 04.2012, OUMNH 2012-01-0063 ; 1 ovig. ♀ cl 5.8 mm, Fars Province, Persepolis, Kor River , leg. P. Bianco & S. Zeruhian, 30.05.76, RMNH.CRUS.D.31507 ; 4 ♀♀ cl 2.67 – 5.0 mm, 1 ♂ cl 2.77 mm, 6 juveniles 2.08 – 2.57 mm, Fars Province, south bank of Lake Maharloo , leg. S. Bauer, 09.06.1975, ZMA.CRUS.D.103251 ; 6 ♀♀ cl 3.52 – 4.41 mm, 1 ♂ cl 3.22 mm , Fars Province, springs around Maharloo Lake (= Daryacheh-ye Maharlu) , 29 ° 25 ' N 52 ° 50 ' E, leg. S. Gorgin, 07.09.1992, RMNH.CRUS.D.42411 GoogleMaps ; 1 ovig. ♀ cl 5.20 mm, 9 ♀♀ cl. 2.97 – 4.85 mm, Fars province, Spring Beedee (= Cheshmeh-Beedee), about 15 km S of Shiraz , 29 ° 24 ' N 52 ° 24 ' E, altitude 1400 m above sea level, RMNH.CRUS.D.42408 GoogleMaps ; 4 ♂♂ cl 2.13 – 2.97 mm, 2 ♀♀ cl 2.23 – 2.97 mm, 22 juveniles, Fars Province, S of Shiraz (= Sjiras), Baba Hadji , leg. K. Lindberg, 11.03.1940, RMNH.CRUS.D.20934 ; 8 ovig. ♀♀ cl 5.05 – 6.04 mm, 2 ♀♀ cl 4.55 – 4.95 mm, Fars province, N of Tashk (= Nargis), E of Shiraz, Spring Gumum (= Cheshmeh-e-Gumum) , 29 ° 48 ' N 53 ° 28 ' E, altitude 1600 m, leg. S. Gorgin, 01.04.1993, RMNH.CRUS.D.42537 GoogleMaps ; 1 ♂ cl 3.81 mm, 9 ♀♀ cl 4.90 – 6.14 mm, Fars province, SE of Shiraz, Kampe-Atashkadeh near Fasa , 29 ° 8 ' N 53 ° 37 ' E, altitude 1700 m, leg. S. Gorgin, 25.03.1993, RMNH.CRUS.D.42538 GoogleMaps ; 2 ♀♀ cl 3.47 – 4.95 mm, 10 ♂♂ cl 3.17 – 3.81 mm, Fars province, SE of Shiraz, W of Maharloo Lake, Barmishur-e-Paeen , 29 ° 27 ' N 52 ° 41 ' E, altitude 1450 m above sea level, leg. S. Gorgin, 12.03.1993, RMNH.CRUS.D.42559 GoogleMaps .

Comparative material examined

Syntypes. C. syriaca Bouvier, 1904 . Syria: 1 ♀ cl 4.7 mm in poor condition, leg. Letourneux, 1882, MNHN-IU-2013-11299 (= MNHN-Na906) ; remainings of 1 specimen, probably female, leg. Letourneux, 1882 MNHN-IU-2013-11298 (= MNHN-Na906) ; components of 6 specimens, cl 4.5 – 4.7 mm, leg. Letourneux, 1882, MNHN-IU-2013-11297 (= MNHN-Na905) .

Description

Cephalothorax and cephalic appendages. Medium-sized shrimp with carapace length 2.1 – 6.1 mm in apparently adult specimens (n = 65). Carapace ( Figs. 2 A View Fig and 4 A View Fig ) smooth, antennal spine almost fused with the inferior orbital angle, pterygostomial angle rounded. Rostrum ( Figs. 2 A, B View Fig and 4 A View Fig ) pointed, slightly sigmoid or almost straight, armed with 19 – 26 teeth throughout dorsal margin, with 5 – 13 teeth on ventral margin, reaching to or (in most specimens) slightly overreaching distal margin of scaphocerite, slightly overreaching antennular peduncle in few specimens, 0.92 – 1.18 (median 0.93, n = 5) times as long as carapace. Rostrum formula 2 – 6 (4) + 15 – 21/5 – 13 (6). Eyes ( Figs. 2 A View Fig and 4 A View Fig ) well developed with pigmented globular cornea. Antennula ( Fig. 4 B View Fig ) and antenna ( Fig. 4 C View Fig ) well developed. Antennular peduncle ( Fig. 4 B View Fig ) 0.72 – 0.92 (median 0.76, n = 4) times as long as carapace, first segment 1.80 – 2.04 (median 1.785, n = 3) times as long as second segment, distolateral angle with an acute projection 0.37 – 0.40 (median 0.38, n = 3) times as long as second segment; second segment 1.79 – 2.25 (median 2.18, n = 3) times length of third segment. Stylocerite pointed, reaching to 0.73 – 0.84 (median 0.80, n = 3) times length of basal segment of antennular peduncle. Scaphocerite ( Fig. 4 C View Fig ) with well-developed distolateral tooth, 3.33 – 4.21 (median 3.83, n = 3) times as long as wide.

Abdominal somites, telson and uropods. Sixth abdominal somite ( Fig. 2 A View Fig ) 0.49 – 0.57 (median 0.53, n = 3) times length of carapace, 1.75 – 1.96 (median 1.82, n = 3) times as long as fifth somite, 0.77 – 0.80 (median 0.77, n = 3) times as long as telson. Telson ( Fig. 4 D, I View Fig ) slightly tapering distally, 3.0 – 3.32 (median 3.30, n = 3) times as long as proximally wide, distal margin convex to triangular, without or with a very small median projection, lateral angles not overreaching distal margin, with 4 – 6 (n = 36) pairs of dorsal short spiniform setae and one pair of short spiniform setae dorsolateral; distal margin with 6 – 16 (n = 36) strong spiniform setae of about equal length. Preanal carina ( Fig. 4 E View Fig ) rounded or triangular without a tooth or spine. Uropodal diaeresis ( Fig. 4 F View Fig ) with 7 – 10 (mostly 9, n = 39) movable spiniform setae, outermost one shorter than lateral angle.

Mouthparts and branchiae. Mandible ( Fig. 5 A View Fig ) without palp, incisor process ending in irregular teeth, molar process truncated. Lower lacinia of maxillula ( Fig. 5 B View Fig ) broadly rounded with long pappose setae and few rows of serrate setae near margin and scattered cuspidate setae proximal, upper lacinia elongate, with numerous distinct cuspidate setae flanked by a row of serrate setae on inner margin and few papose setae subterminal, palp slender with few papose setae and one cuspidate seta near tip. Upper endites of maxilla ( Fig. 5 C View Fig ) subdivided, furnished with numerous pappose, simple and papposerrate setae arranged in rows, palp slender, scaphognathite tapering posteriorly, fringed with long, curved serrulate setae at truncated posterior margin and plumose setae inferior. Palp of first maxilliped ( Fig. 5 D View Fig ) ending in a triangular extension, caridean lobe and flagellum with plumose setae, basis with numerous pappose, papposerrate and serrate setae arranged in rows and tufts. Podobranch on second maxilliped ( Fig. 5 E View Fig ) well developed; exopod slender, overreaching propodal segment, with long plumose setae distally; basis and merus with rows of papose setae, distolateral margin of penultimate segment with several pappose and serrate setae; dactylus with numerous serrate setae flanked by a row of pappose setae. Third maxilliped ( Fig. 5 F View Fig ) slender, with one well developed and one strongly reduced arthrobranch; exopod slender, slightly overreaching the distal margin of antepenultimate segment, with few long plumose setae distally; antepenultimate segment of endopod slender, with several simple setae and some pappose setae basally and few plumose setae distally, inner margin with few short serrate setae; penultimate segment slender, with straight lateral margins, with few plumose setae on dorsal and ventral margin, inner margin with rows of short serrate setae; ultimate segment longer than penultimate segment, tapering distally, ending in a claw-like curved spiniform setae (nail), proximal to the nail about 18 cuspidate setae are arranged in two rows; inner margin dense beset with rows of serrated setae; epipod well developed, with distal hook. One well developed podobranch on second maxilliped, two arthrobranchs (one of them strongly reduced) on third maxilliped, first pereiopod without an arthrobranch. Pleurobranchs present on all pereiopods. Well-developed epipods (with hooks on distal end) present on third maxilliped and first 4 pereiopods. Setobranchs on all pereiopods.

Pereiopods. First and second pereiopods chelate. Chela of first pereiopod ( Fig. 4 G View Fig ) caridinoid in shape, with well-developed palm, 2.03 – 2.44 (median 2.15, n = 6) times as long as wide, 1.16 – 1.44 (median 1.30, n = 6) times as long as carpus; tips of fingers rounded, without hooks; dactylus 2.70 – 3.66 (median 3.01, n = 6) times as long as wide, 0.98 – 1.35 (median 1.14, n = 6) times as long as palm, with tufts of setae distally; carpus slender, slightly excavated distally, 1.63 – 2.41 (median 1.87, n = 7) times as long as wide, 0.86 – 1.00 (median 0.92, n = 7) times as long as merus. Merus not inflated, 2.59 – 3.45 (median 3.17, n = 7) times as long as wide, 1.12 – 1.41 (median 1.19, n = 7) as long as ischium. Chela of second pereiopod ( Fig. 4 H View Fig ) caridinoid in shape, with well-developed palm, 2.22 – 2.89 (median 2.76, n = 6) times as long as wide, 0.74 – 0.86 (median 0.82, n = 6) times as long as carpus; tips of fingers rounded, without hooks, dactylus 3.14 – 4.29 (median 3.55, n = 5) times as long as wide, 1.04 – 1.48 (median 1.18, n = 6) times as long as palm, with tufts of setae distally; carpus slender, 4.45 – 5.22 (median 4.67, n = 6) times as long as wide, 1.05 – 1.21 (median 1.14, n = 5) times as long as merus. Merus not inflated, 4.23 – 5.21 (median 5.17, n = 5) times as long as wide, 1.08 – 1.27 (median 1.18, n = 3) times as long as ischium. Third pereiopod ( Figs. 2 C, E View Fig and 6 A View Fig ) sexually dimorphic; dactylus ( Fig. 6 B View Fig ) 3.10 – 4.29 (median 3.59, n = 6) times as long as wide (terminal claw and spiniform setae on flexor margin included), terminating in 2 large claws, with 27 or 28 accessory spiniform setae on flexor margin in males, terminating in one large claw with 20 – 26 accessory spiniform setae on flexor margin in females; propodus strongly dilated distally and with numerous small spiniform setae on inner margin in adult males, less dilated in females and subadult males, propodus 5.67 – 8.92 (median 8.18, n = 6) times as long as wide, 2.32 – 3.13 (median 2.67, n = 6) times as long as dactylus; carpus 4.18 – 4.96 (median 4.70, n = 5) times as long as wide, 0.60 – 0.69 (median 0.64, n = 5) times as long as propodus, 0.50 – 0.60 (median 0.55, n = 5) times as long as merus, with one large spiniform setae near distal margin; merus 5.85 – 7.64 (median 6.97, n = 5) times as long as wide, 1.67 – 2.02 (median 1.82, n = 5) times as long as carpus, bearing 2 or 3 strong movable spiniform setae on externo-inferior margin; ischium with one spiniform setae (lacking in one female specimen examined). Fourth pereipopod ( Figs. 2 D, 2 F View Fig , 6 C View Fig – D), similar to third but slightly smaller. Fifth pereiopod ( Fig. 6 E View Fig ) slender; dactylus ( Fig. 6 F View Fig ) 3.17 – 4.09 (median 3.81, n = 5) times as long as wide (terminal claw and spiniform setae on flexor margin included), terminating in one large claw, with 33 – 52 spiniform setae on flexor margin; propodus with small spiniform setae on ventral margin, more densely in distal part, distal pair of spiniform setae not enlarged, propodus 7.71 – 9.20 (median 8.0, n = 5) times as long as wide, 2.40 – 2.84 (median 2.55, n = 5) times as long as dactylus; carpus 4.0 – 4.21 (median 4.17, n = 3) times as long as wide, 0.56 – 0.58 (median 0.57, n = 3) times as long as propodus, 0.63 – 0.67 (median 0.63, n = 3) times as long as merus, with 1 strong spiniform setae near distal margin; merus 5.50 – 6.40 (median 5.94, n = 3) times as long as wide, 1.49 – 1.60 (median 1.58, n = 3) times as long as carpus, bearing 2 – 3 strong appressed movable spiniform setae on externo-inferior margin. Ischium without a spiniform seta.

Pleopods. Endopod of male's first pleopod ( Figs. 3 C View Fig and 6 G View Fig ) slender leaf-like, subdistally with a distinct appendix interna furnished with numerous small cincunnuli near tip, 3.33 – 3.85 (n = 2) times as long as proximal width, 0.54 – 0.67 (n = 2) times as long as exopod, with long setae on outer and distal margin, with few short pappose setae on basal part of inner margin. Appendix masculina on male second pleopod ( Figs. 3 D View Fig and 6 H, I View Fig ) rod-like, 7.69 (n = 1) times as long as wide, 0.57 (n = 1) times as long as endopod, armed with strong spiniform setae on inner margin and distal margin; appendix interna arising from about 0.4 times length of appendix masculina, failing short of tip of appendix masculina.

Sexual dimorphism. Males similar to females except size, third and fourth pereiopods ( Figs. 2 C View Fig – F, 6 A – D) and sexual appendages ( Figs. 3 A View Fig – D, 6 G – I). The main morphological differences from females lead in the shape and spinulation of distal segments of third and fourth pereiopods and structure of the endopod of first pleopod as well as the presence of an appendix masculina in second pleopod ( Figs. 3 D View Fig , 6 G View Fig – I).

Reproductive biology. Ovigerous females with few large eggs ( Fig.3 A View Fig ); size of developed eggs(with eyes) 1.07 – 1.13 × 0.61 – 0.73 mm.

Size. Postorbital carapace length of apparently adult specimens 2.1 – 6.1 mm.

Colouration. Unknown.

Distribution. The species is known from freshwaters in Iran, and specifically from rivers, springs and lakes of the Fars province ( Fig. 1 B View Fig ).

Remarks. The original description of C. fossarum published in 1862 ( Heller 1862) is rather brief and does not contain many details on morphology of third pereiopods, branchiae or sexual appendages. Reexamination of the type material as well as examination of additional material deposited at the OUMNH and RMNH revealed a remarkable sexual dimorphism of this species not yet described in other species of genus Caridina . Although some morphological characters of C. fossarum , e.g., the reduced branchial formula and the striking sexual dimorphism with propodi of third pereiopods dilated distal and beset with numerous spiniform setae in males are matching the description of the genus Puteonator , it might be premature to assign C. fossarum to this genus as in molecular analysis this species is found in a narrow clade with other members of genus Caridina and no material of Puteonator iraquiensis Gurney, 1987 is available for DNA analysis.