Caridina shahrazadae, Klotz & von Rintelen & Christodoulou, 2019

Caridina shahrazadae View in CoL sp. nov.

( Figs. 14 View Fig – 17)

Material examined

Holotype. ♀ cl 5.7 mm, Iran, Hamadan Province, Pirsalam Lagoon, Asadabad , 34 ° 39.452 ' N 47 ° 55.888 ' E, leg. A. Ghane, 02.2008, OUMNH 2008-13-0001 GoogleMaps .

Paratypes. Iran: 5 ♀♀ cl 4.1 – 5.7 mm OUMNH 2008-13-0001 , same data as holotype; GoogleMaps 2 ♂♂ cl 4.1 mm, 1 ♀ cl 3.7 mm, Hamadan Province, leg. A. Ghane, 04.01.2008, QUMNH 2011-01-0023 ; 6 ♀♀ cl 4.3 – 5.1 mm, 4 ♂♂ cl 3.5 – 3.8 mm, Fars Province, Nurabad, Spring near the village Sarab-e-Bahram , 30 ° 01 ' N 51 ° 33 ' E, altitude ca. 920 m, leg. S. Gorgin 05.09.1994, RMNH.CRUS.D.46090 GoogleMaps ; 2 ovig. ♀♀ cl 4.1 mm, 6 ♀♀ cl 3.5 – 4.3 mm, 1 ♂ cl 3.1 mm, Kermanshah Province, Sarab-e-Dehlor , 34 ° 23 ' N 47 ° 52 ' E, 08.02.1996, leg. friend of S. Gorgin, don. S. Gorgin, RMNH.CRUS.D.46889 GoogleMaps ; 3 ♂♂ cl 3.1 – 3.4 mm, 1 ♀ cl 5.0 mm, Khuzestan Province, road between Behbahan and Ramhormoz , 30 ° 39 ' N 50 ° 09 ' E; 29.12.1994, leg. S. Gorgin, RMNH.CRUS.D.46151 GoogleMaps ; 2 ♂♂ cl 3.2 and 3.6 mm, 2 ovig. ♀♀ cl 4.0 and 4.6 mm, Lorestan Province, near Kuhdasht, Spring Seeyab (= Chesmeh-e-Seeyab), Tang-e-Seeyab , 33 ° 23 ' N 47 ° 12 ' E; altitude 890 m, 17.11.1995, leg. S. Gorgin, RMNH.CRUS.D.46695 GoogleMaps .

Comparative material examined

Caridina chauhani Chopra & Tiwari, 1949 , India: 1 ovig. ♀, Karnataka, Jog Falls , 14 ° 13.7 ' N 74 ° 48.72 ' E, leg. Riedel, 23.03.2007, ZMB 30756 GoogleMaps ; 1 ♂ cl 2.9 mm, 2 ♀♀ cl 2.7 and 3.2 mm, 3 ovig. ♀♀ cl 3.9 – 4.0 mm, Karnataka, MH Patna Lake near national highway 73 , 13 ° 19.85 ' N 76 ° 59.48 ' E, leg. F. Riedl, 02.12.2014, ZMB 30759 GoogleMaps ; 1 ♂ cl 3.1 mm, 1 ♀ cl 4.9 mm, 1 ovig. ♀ cl 5.1 mm, Karnataka, river near Edakkara , 11 ° 21.65 ' N 76 ° 18.73 ' E, leg. F. Riedl, 07.12.2014, ZMB 30760 GoogleMaps .

Description

Cephalothorax and cephalic appendages. Medium-sized shrimp with carapace length 3.1 – 5.7 mm in apparently adult specimens (n = 36). Carapace ( Fig. 14 A View Fig ) smooth, antennal spine slightly separated from the inferior orbital angle, pterygostomial angle rounded. Rostrum ( Fig. 14 A View Fig ) slightly sigmoid or almost straight, armed with 13 – 26 teeth throughout dorsal margin, with 3 – 10 teeth on ventral margin, reaching to distal margin of scaphocerite in most specimens, in some specimens reaching to distal end of antennular peduncle, 0.40 – 0.83 (median 0.8, n = 3) times as long as carapace. Rostrum formula 1 – 4 + 10 – 23/3 – 10. Eyes ( Fig. 14 A View Fig ) well developed with pigmented globular cornea. Antennula ( Fig. 14 B View Fig ) and antenna ( Fig.14 C View Fig ) well developed. Antennular peduncle ( Fig.14 B View Fig ) 0.35 – 0.71 (median 0.51, n = 4) times as long as carapace, first segment 1.77 – 2.05 (median 1.86, n = 4) times as long as second segment, distolateral angle with an acute projection 0.38 – 0.55 (median 0.45, n = 4) times as long as second segment; second segment 2.17 – 2.61 (median 2.40, n = 4) times length of third segment. Stylocerite ( Fig.14 B View Fig ) pointed, reaching to 0.84 – 0.89 (median 0.86, n = 3) times length of basal segment of antennular peduncle. Scaphocerite ( Fig. 14 C View Fig ) with well-developed distolateral tooth, 3.75 times as long as wide.

Abdominal somites, telson and uropods. Sixth abdominal somite 0.50 – 0.60 (n = 2) times length of carapace, 1.69 – 2.00 (n = 2) times as long as fifth somite, 0.84 times as long as telson. Telson ( Fig. 14 D, I View Fig ) slightly tapering distally, distal margin rounded to broadly convex without a median projection, lateral angles not overreaching distal margin, dorsal with 5 – 6 (n = 2) pairs of short spiniform setae and one pair of short spiniform setae dorsolateral; distal margin with 9 – 10 (n = 5) strong spiniform setae. Lateral pair longer than intermediate ones, sublateral pair shortest. Preanal carina ( Fig.14 E View Fig ) low, rounded, mostly with a small hump, without a tooth or spine. Uropodal diaeresis ( Fig. 14 F View Fig ) with 9 – 10 (n = 3) movable spiniform setae, outermost one distinct shorter than lateral angle.

Mouthparts and branchiae. Mandible ( Fig. 15 A) without palp, incisor process ending in irregular teeth, molar process truncated. Lower lacinia of maxillula ( Fig. 15 B) broadly rounded to subrectangular with long pappose setae and few rows of serrate setae near margin, upper lacinia elongate, with numerous distinct cuspidate setae flanked by a row of serrate setae on inner margin and few pappose setae subterminal, palp slender with few pappose setae and one cuspidate seta near tip. Upper endites of maxilla ( Fig. 15 C) 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. 15 D) ending in a long, fingerlike extension, caridean lobe and flagellum with plumose setae, basis with numerous pappose, papposerrate and serrate setae arranged in rows and tufts. Endopod reaching beyond distal margin of caridean lobe. Podobranch on second maxilliped ( Fig.15 E) reduced to a lamina with few short finger-like projections; exopod slender, overreaching propodal segment, with long plumose setae distally; basis and merus with rows of pappose 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. 15 F) slender, with one well developed and one small arthrobranch; exopod slender, slightly overreaching the distal margin of antepenultimate segment, with few long plumose setae distally; antepenultimate segment of endopod slender, with some pappose setae basally, distal with few short simple setae; penultimate segment slender, with straight lateral margins, with few plumose setae on dorsal and ventral margin, inner margin with rows of short serrated setae; ultimate segment longer than penultimate segment, tapering distally, ending in a claw-like curved spiniform setae (nail), proximal to the nail about 8 cuspidate setae; inner margin dense beset with rows of serrate setae, some serrate setae also on dorsal margin; epipod well developed, with distal hook. Podobranch on second maxilliped reduced to a lamina with few short protuberances distally, two arthrobranchs (one of them reduced) on third maxilliped, first pereiopod with arthrobranch reduced to a worm-like structure. Pleurobranchs present on all pereiopods. Well-developed epipods (with hooks on distal end) present on third maxilliped and first four pereiopods. Setobranchs on all pereiopods.

Pereiopods. First and second pereiopods chelate. Chela of first pereiopod ( Fig. 14 G View Fig ) caridinoid in shape, with well-developed palm, 1.78 – 2.24 (median 2.08, n = 5) times as long as wide, 1.36 – 1.71 (median 1.39, n = 5) times as long as carpus; tips of fingers rounded, with strong hooks and tufts of setae distally; dactylus 2.30 – 3.25 (median 2.46, n = 3) times as long as wide, 0.92 – 1.24 (median 1.19, n = 5) times as long as palm; carpus stout, slightly excavated distally, 1.40 – 2.08 (median 1.81, n = 5) times as long as wide, 0.80 – 0.95 (median 0.87, n = 4) times as long as merus. Merus not inflated, 2.50 – 3.31 (median 2.75, n = 4) times as long as wide, 1.14 – 1.25 (n = 2) as long as ischium. Chela of second pereiopod ( Fig. 14 H View Fig ) caridinoid in shape, with well-developed palm, 1.76 – 2.47 (median 2.34, n = 4) times as long as wide, 0.88 – 0.91 (median 0.90, n = 4) times as long as carpus; tips of fingers rounded, with hooks and tufts of setae distally, dactylus 3.80 – 4.28 (n = 2) times as long as wide, 1.15 – 1.57 (median 1.42, n = 4) times as long as palm; carpus slender, 3.79 – 4.31 (median 4.0, n = 4) times as long as wide, 0.95 – 0.96 (n = 2) times as long as merus. Merus not inflated, 4.69 – 5.04 (n = 2) times as long as wide, 1.36 times as long as ischium. Third pereiopod ( Fig. 16 A, H) slightly dimorphic between sexes; dactylus ( Fig. 16 B) 2.23 – 2.47 (n = 2) times as long as wide (terminal claw and spiniform setae on flexor margin included), terminating in 2 large claws, with 4 or 5 accessory curved spiniform setae on flexor margin in males, 3.6 times as long as wide (terminal claw and spiniform setae on flexor margin included) terminating in one large claw with 6 or 7 accessory straight spiniform setae on flexor margin in females; propodus not dilated distally and with two rows of small spiniform setae on inner margin, slightly curved in males, propodus 8.15 – 9.38 (median 8.18, n = 3) times as long as wide, 2.90 – 3.86 (median 3.32, n = 4) times as long as dactylus; carpus 5.31 – 5.57 (n = 2) times as long as wide, 0.71 – 0.73 (n = 2) times as long as propodus, 0.58 – 0.64 (n = 2) times as long as merus, with one large spiniform seta near distal margin; merus 5.90 – 7.10 (n = 2) times as long as wide, 1.57 – 1.72 (n = 5) times as long as carpus, bearing 3 strong movable spiniform setae on externo-inferior margin; ischium with one spiniform seta. Fourth pereipopod similar to third but slightly smaller ( Fig. 16 C – D). Fifth pereiopod ( Fig. 16 E) slender; dactylus ( Fig. 16 F) 3.14 – 3.59 (median 3.75, n = 3) times as long as wide (terminal claw and spiniform setae on flexor margin included), terminating in one large claw, with 28 – 45 spiniform setae on flexor margin; propodus with 2 rows of small spiniform setae on ventral margin, distal pair of spiniform setae not enlarged, propodus 10.22 – 12.19 (median 11.20, n = 3) times as long as wide, 3.07 – 3.39 (median 3.08, n = 3) times as long as dactylus; carpus 4.46 – 5.22 (n = 2) times as long as wide, 0.47 – 0.52 (n = 2) times as long as propodus, 0.64 (n = 2) times as long as merus, with 1 strong spiniform setae near distal margin; merus 6.06 – 6.67 (n = 2) times as long as wide, 1.55 – 1.57 (n = 2) times as long as carpus, bearing 2 strong movable spiniform setae on externo-inferior margin. Ischium without a spiniform seta.

Pleopods. Endopod of male's first pleopod ( Fig. 17 A) slender leaf-like, tip slightly curved inwards, without an appendix interna, 1.97 times as long as proximal width, 0.40 times as long as exopod, with simple setae on proximal 2/3 of inner margin, with pappose setae on distal and outer margin. Appendix masculina on male second pleopod ( Fig. 17 B – C) rod-like, 11.08 times as long as wide, 0.76 times as long as endopod, armed with strong spiniform setae on inner and distal margin; appendix interna arising from about 0.4 times length of appendix masculina, reaching to about 0.6 times length of appendix masculina.

Sexual dimorphism. Males similar to females except size, third and fourth pereiopods and sexual appendages. The main morphological differences from females lead in the shape and spinulation of third and fourth pereiopod dactyli ( Fig. 16 B, H) and structure of the endopod of first and second pleopods as well as presence of an appendix masculina ( Figs. 16 G and 17 A – C).

Reproductive biology. Ovigerous females with few large eggs; size of developed eggs (with eyes) 0.98 – 1.03 × 0.61 – 0.64 mm.

Size. Postorbital carapace length of apparently adult specimens 3.1 – 5.7 mm.

Colouration. Unknown.

Distribution. The species is known from freshwaters in Hamadan, Fars, Kermanshah, Khuzestan, Lorestan Provinces of Iran ( Fig. 1 B View Fig ).

Etymology. C. shahrazadae sp. nov. is named after Shahrazad, the character that portraits the storyteller in the book One Thousand and One Nights.

Remarks. C. shahrazadae sp. nov. is similar to C. fossarum in having few and large-sized eggs. The new species can be easily distinguished from C. fossarum by the reduced branchial formula found in the latter. Further, the new species can by distinguished by the absence of an appendix interna in the male's first pleopod endopod vs. the presence of a well-developed appendix interna subdistally on the endopod in C. fossarum . The two species can also be distinguished by lacking prominent sexual dimorphism of propodi of the third and fourth pereiopods (with few spiniform setae in males and females and not strongly inflated distally) vs. the propodi of the third and fourth pereiopods with numerous small setae and being strongly inflated distally in males of C. fossarum . C. shahrazadae sp. nov. is also similar to C. chauhani from Karnataka, India and Caridina rajadhari Bouvier, 1918 from Chattisgarh, India. The new species from Iran can be distinguished from these species by lacking an appendix interna on the first pleopod of male specimens, a shorter rostrum (0.40 – 0.83 times as long as carapace vs. 0.99 – 1.25 times as long in C. chauhani ) with a lower number of teeth on the dorsal margin of the rostrum (16 – 26 vs. 25 – 33), the distal segment of third maxilliped about as long as median segment (vs. distal segment shorter than median in C. chauhani ), arthrobranch on first pereiopod and podobranch on second maxilliped reduced (vs. well developed in C. chauhani ), a higher number of spiniform setae on distal margin of telson (9 – 10 vs. 6 in C. chauhani ), larger eggs (developed eggs 0.98 – 1.03 × 0.61 – 0.64 mm vs. 0.61 – 0.68 mm x 0.38 – 0.39 mm in C. chauhani or 0.50 – 0,61 × 0.30 – 0.50 mm in Caridina radjadhari ).