Palaemon

Tzomos, Theodoros & Koukouras, Athanasios, 2015, Redescription of Palaemon antennarius H. Milne Edwards, 1837 and Palaemon migratorius (Heller, 1862) (Crustacea, Decapoda, Palaemonidae) and description of two new species of the genus from the circum-Mediterranean area, Zootaxa 3905 (1), pp. 27-51 : 49

Key to identification of the inland Palaemon species from the circum-Mediterranean area

1. Fifth pleuron distal end not rounded ( Figures 2 E, 7B, 10A)..................................................... 2

- Fifth pleuron distal end rounded ( Figure 6 B, 9B)............................................................. 7

2. Fifth pleuron distal end strongly pointed ( Figure 2 E, 7B)....................................................... 3

- Fifth pleuron distal end subquadrate and not pointed ( Figure 10A )............................................... 6

3. Telson with two plumose setae on posterior margin ( Figures 5 A, 5B, 8C, 10C); third maxilliped exopod equal or longer than isciomerus ( Figure 3 H); endopod of first pleopod of male clearly shorter than exopod ( Figures 4 F, 8A); appendix masculina shorter than the endopod of the second pleopod ( Figure 4 G).................................................... 4

- Telson with 2–6 plumose setae on posterior margin (Figure 13 in Azzouna, 1994); third maxilliped exopod shorter than isciomerus ( Figure 7 in Azzouna, 1994); endopod of first pleopod of male slightly shorter than exopod (Figure 12 in Azzouna, 1994); appendix masculina longer than the endopod of the second pleopod (Figure 12 in Azzouna, 1994)..... P. mesogenitor

4. Telson plumose setae fail to overpass the inner spines ( Figure 5 B); first maxilliped endites separated with their inner edges forming an obtuse angle ( Figure 3 F); branchiostegal tooth originating just before anterior margin of carapace ( Figure 2 C)... 5

- Telson plumose setae overpass the inner spines ( Figure 10 C); first maxilliped endites are arranged almost in a straight line forming just a notch between them ( Figure 10 F); branchiostegal tooth marginal ( Figure 2 A in González-Ortegón & Cuesta, 2006)........................................................................................ P. varians

5. Telson with 40–50 pairs of marginal lanceolate setae ( Figures 8 C, 8D); in males, endopod of the first pleopod deeply concave on the mesial portion of inner margin ( Figure 8 A); in females, endopod of the first pleopod with concave inner margin and rounded tip ( Figure 8 B).................................................................. P. colossus sp. nov.

- Telson with 0–6 pairs of marginal lanceolate setae just proximally ( Figure 5 A); in males, endopod of the first pleopod slightly concave on the mesial portion of inner margin ( Figure 4 F); in females, endopod of the first pleopod lanceolate ( Figure 4 H)............................................................................................. P. antennarius

6. Telson with two plumose setae on posterior margin ( Figure 6 c in Holthuis, 1961); endopod of first pleopod of male almost as long as exopod ( Figure 8 c in Holthuis, 1961); appendix masculina longer than the endopod of the second pleopod ( Figure 8 d in Holthuis, 1961).............................................................................. P. t u rc o r u m

- Telson with 4–6 plumose setae on posterior margin ( Figure 10 E); endopod of first pleopod of male clearly shorter than the exopod; appendix masculina shorter than the endopod of the second pleopod................................ P. zariquieyi

7. Telson always with two plumose setae on posterior margin ( Figure 9 C).............................. P. minos sp. nov.

- Telson with 4–12 plumose setae on posterior margin ( Figures 6 F, 10D)........................................... 8

8. Telson with 10–12 plumose setae on posterior margin ( Figure 10 D); third maxilliped exopod shorter than ischiomerus ( Figure 10 G); outer margin of scaphocerite concave ( Figure 10 H)......................................... P. mesopotamicus

- Telson with 4–7 plumose setae on posterior margin ( Figure 6 F); third maxilliped exopod equal or longer than ischiomerus; outer margin of scaphocerite straight........................................................... P. migratorius

Figures

FIGURE 2. Palaemon antennarius H. Milne Edwards, 1837. A. Whole animal, lateral view. B. Eye, dorso-mesial view. C. Frontal region. D. Antennula. E. Fifth pleuron. F. Uropod. G. Scaphocerite. Lectotype ♀ (pocl 7.7 mm), MNHN – IU – 2013 – 9296 (= MNHN – Na 1500), Trasimeno Lake, Italy. Scale bar indicates 5 mm (A), 1 mm (B), 3 mm (C, D, F, G), 2 mm (E).

FIGURE 3. Palaemon antennarius H. Milne Edwards, 1837. A. Thoracic sternal armature. B. Abdominal sternal armature. C. Mandible. D. Maxillula. E. Maxilla. F. First maxilliped. G. Second maxilliped. H. Third maxilliped. A – H ♀ paralectotype (pocl 8.0 mm), MNHN – IU – 2013 – 4023 (= MNHN – Na 1500), Trasimeno Lake, Italy; A – B ♂ (pocl 6.6 mm), Trasimeno Lake, 6.9. 1974, coll. Froglia C. & E. Peloni. Scale bar indicates 1.5 mm (A, B, E – H), 1 mm (C, D).

FIGURE 4. Palaemon antennarius H. Milne Edwards, 1837. A. First pereiopod. B. Second pereiopod. C. Third pereiopod. D. Fourth pereiopod. E. Fifth pereiopod. F. First pleopod male. G. Second pleopod male. H. First pleopod female. I. Second pleopod female. J. Third pleopod female. K. Fifth pleopod female. A – E, H – K ♀ paralectotype (pocl 8.0 mm), MNHN – IU – 2013 – 4023 (= MNHN – Na 1500), Trasimeno Lake, Italy; F – G ♂ (pocl 6.6 mm), Trasimeno Lake, 6.9. 1974, coll. Froglia C. & E. Peloni. Scale bar indicates 2 mm.

FIGURE 5. Palaemon antennarius H. Milne Edwards, 1837. A. Telson. B. Telson distal part. Lectotype ♀ (pocl 7.7 mm), MNHN – IU – 2013 – 9296 (= MNHN – Na 1500), Trasimeno Lake, Italy. Scale bar indicates 3 mm (A), 1 mm (B).

FIGURE 6. Palaemon migratorius (Heller, 1862). A. Whole animal, lateral view. B. Fifth pleuron. C. First maxilliped. D. Thoracic sternal armature. E. Abdominal sternal armature. F. Telson distal part. A – B, D – F lectotype ♀ (pocl 8.9 mm), NHMW 25559, Egypt; C ♀ paralectotype (pocl 6.9 mm), NHMW 7733, Egypt. Scale bar indicates 2 mm (A), 1 mm (B, C), 1.5 mm (D, E), 0.5 mm (F).

FIGURE 7. Palaemon colossus sp. nov. A. Whole animal, lateral view. B. Fifth pleuron. C. Maxillula. D. Thoracic sternal armature. E. Abdominal sternal armature. A – B, D – E holotype ♀ (pocl 8.5 mm), OUMNH. ZC. 2014 – 13 – 001, Epta Piges, Rhodes Island, Greece; C, D – E, ♂ (pocl 6.0 mm), ZMAUTH – G 3 – 30, Epta Piges, Rhodes Island, Greece, 2002, coll. Anastasiadou Ch. Scale bar indicates 4 mm (A), 2 mm (B), 0.5 mm (C), 1.5 mm (D, E).

FIGURE 8. Palaemon colossus sp. nov. A. First pleopod male. B. First pleopod female. C. Telson. D. Marginal lanceolate setae of telson. A ♂ (pocl 6.0 mm), ZMAUTH – G 3 – 30, Epta Piges, Rhodes Island, Greece, 2002, coll. Anastasiadou Ch.; B – D holotype ♀ (pocl 8.5 mm), OUMNH. ZC. 2014 – 13 – 001, Epta Piges, Rhodes Island, Greece. Scale bar indicates 1 mm (A – C), 0.4 mm (D).

FIGURE 9. Palaemon minos sp. nov. A. Whole animal, lateral view. B. Fifth pleuron. C. Telson distal part. D. Thoracic sternal armature. E. Abdominal sternal armature. A – E holotype ♂ (pocl 4.5 mm), OUMNH. ZC. 2014 – 13 – 003, Kourna Lake, Crete, Greece; D – E ♀ (pocl 7.0 mm), ZMAUTH – G 3 – 31, Kourna Lake, Crete, Greece; Scale bar indicates 4 mm (A), 1.5 mm (B, D, E), 0.5 mm (C).

FIGURE 10. A. Fifth pleuron of P. zariquieyi. B. Maxillula of P. varians. C. Telson distal part of P. v a r i an s. D. Telson distal part of P. mesopotamicus. E. Telson distal part of P. zariquieyi. F. First maxilliped of P. varians. G. Third maxilliped of P. mesopotamicus. H. Scaphocerite of P. mesopotamicus. A, E, ♀ (pocl 7.0 mm), OUMNH. ZC. 2004 – 11 – 001, Las Turberas, Prat de Cabamas, Torreblanca, Spain; B – C, F, ♀ (pocl 7.2 mm), NHM 1959.10.17.72 – 82, Roose Cote, Power Station, Morecambe Bay, United Kingdom; D, G – H, ♀ (pocl 6.9 mm), SMF – TSH 30 / 88, Khabur river, Syria. Scale bar indicates 3 mm (A), 1 mm (B – E), 1.5 mm (F), 2 mm (G), 5 mm (H).