Appendicularia Lahille 1890
Creators: name: Karunarathne, Krishan D.
name: Croos, M. D. S. T. De
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Appendicularia

description: Key to the Appendicularia species of Sri Lanka
(based on Tokioka 1960; Bückmann 1969; Fenaux 1993, 1998; Aravena & Palma 2002)
1 Usually trunk flattened or spindle-shaped; endostyle curved upwards; tail orientated at the right angle to body: Family Fritillaridae............................................................................................. 11
- Trunk oval in shape and on the same axis as tail; endostyle straight: Family Oikopleuridae ........................... 2
2 Digestive tract incompletely developed; no oral glands and subchordal cells....................... Megalocercus huxleyi
- Digestive tract completely developed..................................................................... 3
3 Digestive tract forms a loop broadly open to the front; oral glands and subchordal cells present......... Stegosoma magnum
- Digestive tract compactly coiled into a nucleus.............................................................. 4
4 Oral glands and subchordal cells present................................................................... 8
- Oral glands and subchordal cells absent.................................................................... 5
5 Ceacum developed upwards and backwards............................................... Oikopleura fusiformis
- Ceacum directed either upward or backward only............................................................ 6
6 Small ceacum directed backwards......................................................... Oikopleura gracilis
- Finger-shaped ceacum directed upwards................................................................... 7
7 Ceacum close to the cardial region....................................................... Oikopleura longicauda
- Ceacum separated from the cardial region by a wide bight.................................... Oikopleura intermedia
8 Numerous subchordal cells, arranged in two rows............................................. Oikopleura albicans
- Subchordal cells few, arranged in a single row.............................................................. 9
9 With small postcardial ceacum on the left stomach lobe..................................... Oikopleura cophocerca
- Without postcardial ceacum on the left stomach lobe........................................................ 10
10 One spindle-shaped cell................................................................ Oikopleura rufescens
- Two spindle-shaped cells.................................................................. Oikopleura dioica
11 Anterior ovaries......................................................................... Tectillaria fertilis
- Posterior ovaries..................................................................................... 12
12 Distal end of the tail acuminate......................................................................... 15
- Distal end of the tail notched........................................................................... 13
13 Amphichordal cells absent................................................................ Fritillaria borealis
- Amphichordal cells present............................................................................ 14
14 Testis trapezoidal and laterally encircled by the ovary in a string.................................. Fritillaria venusta
- Testis Y-shaped and ovary spherical........................................................ Fritillaria pellucida
15 Ciliated rings of the branchial passages oval and elongated...................................... Fritillaria fraudax
- Ciliated rings of the branchial passages circular............................................................ 16
16 Trunk oval, compressed dorsoventrally...................................................... Fritillaria gracilis
- Trunk elongate, bent upwards in the digestive nucleus region..................................... Fritillaria formica
description: Published as part of Karunarathne, Krishan D. & Croos, M. D. S. T. De, 2021, Pelagic tunicates (Appendicularia and Thaliacea) of Sri Lanka: two first records with an annotated checklist, pp. 352-376 in Zootaxa 5067 (3) on page 370, DOI: 10.11646/zootaxa.5067.3.2, http://zenodo.org/record/5681899