Table 4 Comparison of the morphological characters among four Neocaridina species in Taiwan and their identification keys
From: Geographical and temporal origins of Neocaridina species (Decapoda: Caridea: Atyidae) in Taiwan
| Â | N. davidi | N. saccam | N. ketagalan | N. sp. |
|---|---|---|---|---|
1. The merus of the 1st pereiopod (as long as wide) | 2.5 | 1.4–1.7 | 1.8–2.2 | 1.8–2.0 |
2. The carpus of the 1st pereiopod in the male (as long as high) | 1.7 | 1.4 | 1.6 | 1.2–1.5 |
3. The number of accessory spines on the dactylus of the 3rd pereiopod | 5–8 | 4–6 | 4–6 | 4–6 |
4. Endopod of the male 1st pleopod (as long as wide) | 1.2 | 1.4 | 1.4 | 1.7 |
5. Propodus of the 3rd pereiopod (as long as dactylus) | 3.0 | 2.7–3.2 | 3.5–3.9 | 2.7–3.0 |
6. Dactylus of the 5th pereiopod (as long as broad) |  | 3.0–3.5 | 3.7–4.0 | 2.9–3.4 |
7. The number of spinules on the uropodal diaeresis | 9–13 | 12–14 | 14–17 | 13–14 |
Keys to Taiwan species of the Neocaridina group: | ||||
1a. Rostrum reaching slightly beyond the end of the 1st segment of the antennular peduncle, endopod of the male 1st pleopod 1.7 times as long as wide | N. sp. | |||
1b. Rostrum reaching or more than the mid-length of the 2nd of antennular peduncle, endopod of the male 1st pleopod less than 1.7 times as long as wide | 2 | |||
2a. Carpus of 1st pereiopod in the male more than 1.6 times as long as high | 3 | |||
2b. Carpus of first pereiopod in the male 1.4 times as long as high | N. saccam | |||
3a. Propodus of the 3rd pereiopod more than 3.5 times as long as dactylus, pleopod 1.3–1.5 times as long as wide, endopod of the male 1st pleopod less than 1.4 times as long as wide | N. ketagalan | |||
3b. Propodus of the 3rd pereiopod less than 3.5 times as long as dactylus, endopod of the male 1st pleopod less than 1.2 times as long as wide | N. davidi | |||