Capitellidae

Magalhães, Wagner F. & Bailey-Brock, Julie H., 2012, Capitellidae Grube, 1862 (Annelida: Polychaeta) from the Hawaiian Islands with description of two new species, Zootaxa 3581, pp. 1-52 : 2-3

Key to species of Capitellidae from the Hawaiian Islands

1. Thorax with 9 chaetigers, genital spines present from chaetigers 8–9............................................. 2

– Thorax with 9 or more chaetigers, genital spines absent....................................................... 6

2. Presence of filamentous branchiae on posterior segments.............................. Capitella singularis comb. nov.

– Branchiae absent...................................................................................... 3

3. Capillary chaetae in mature individuals present on segments 1–7................................................ 4

– Capillary chaetae in mature individuals restricted to segments 1–4............................................... 5

4. Chaetigers 1–6 with capillaries only, chaetiger 7 with notochaetae and neurohooks, males and females with chaetigers 8 and 9 with genital spines on notopodia and neurohooks................................................ Capitella giardi

– Genital spines on segments 8 and 9 in adult males only; females with distinct methyl green staining pattern, with chaetiger 4 darkly stained and chaetigers 7–8 with lateral glandular patches intensely stained.......................... Capitella sp.

5. Capillary chaetae in mature individuals restricted to chaetigers 1–4; chaetigers 5–7 with hooded hooks only; females with chaetigers 8–9 having hooded hooks and males with chaetigers 8–9 having notopodial spines and neuropodial hooks............................................................................................... Capitella minima

– Capillary chaetae in mature individuals restricted to chaetigers 1–3; mature females with chaetigers 4–9 with hooded hooks only.................................................................................... Capitella jonesi

6. Thorax with 9–11 chaetigers, anal plaque with spines present................................................... 7

– Thorax with 10 or more chaetigers, anal plaque with spines absent............................................... 9

7. Thorax with 9 or 10 chaetigers; incompletely developed anal plaque with one pre-pygidial segment with notopodial spines and neuropodial hooks, anal plaque with two acicular hooks per notopodial lobe; two inflated, heart-shaped anal cirri.................................................................................. Scyphoproctus edmondsoni sp. nov.

– Anal plaque completely developed with short, digitate anal cirri................................................. 8

8. Thorax with 11 chaetigers; three pre-plaque segments with triangular lateral lobes and notoacicula; notoacicula on plaque numbering 8:9:7 on largest specimen and 3:4:2 on smallest (others with 3:6:4; 4:6:5); anterior two pre-plaque notopodia fused............................................................................... Scyphoproctus pullielloides

– Thorax with 10 or 11 chaetigers; one pre-plaque segment with up to eight acicular hooks in both rami; anal plaque with up to seven sets of spines (e.g. 4:3:2:2:2:1:1; 2:1:1:1:1:1:1; 3:2:2:2:1:1; 4:3:1:1:1).......................... Scyphoproctus sp.

9. Thorax with 11 chaetigers............................................................................. 10

– Thorax with 10 chaetigers, capillary chaetae present from chaetigers 1–4 and hooded hooks from 5–10.................................................................................................. Mediomastus californiensis

10. Thoracic chaetae all capillaries.......................................................................... 11

– Thoracic chaetae capillaries from chaetigers 1–5 and hooded hooks from chaetigers 6–11......... Heteromastus cf. filiformis

11. First two abdominal segments with only capillaries on both rami............................................... 12

– Abdominal segments with hooded hooks only.............................................................. 14

12. Absence of a distinct MGSP; dorsally inflated neuropodial lobes; anterior abdominal notopodial lobes completely free.............................................................................. Notodasus dasybranchoides sp. nov.

– Distinct MGSP on thorax and abdomen;.................................................................. 13

13. Thorax and first two abdominal segments stain darker than rest of abdomen; subsequent eight abdominal segments with two dorsal transverse darkly stained bands that are separated by unstained notopodial lobes and lateral organs..... Notodasus kristiani

– Thorax and first two abdominal segments stain darker than rest of abdomen; subsequent 14 abdominal segments with two dark dorso-lateral longitudinal bands that are separated by unstained notopodial lobes and lateral organs...... Notodasus harrisae

14. Chaetiger 1 uniramous; transition between thorax and abdomen marked by dark brown glandular bands; hooded hooks with only two teeth in basal row; branchiae present as 2–3 digitate lobes; pygidium with four digitate lobes........ Capitellethus cinctus

– Chaetiger 1 uni- or biramous; hooded hooks with more than two teeth in basal row; branchiae absent.................. 15

15. Chaetiger 1 uniramous with only notochaetae; hooded hooks with at least three rows of teeth and 5–7 teeth in basal row; abdominal parapodial lobes enlarged, notopodial lobes approaching each other dorsally and neuropodial lobes well separated ventrally; without a distinct MGSP.......................................................... Notomastus tenuis

– Chaetiger 1 biramous; hooded hooks with at least two rows of teeth and 4–5 teeth in basal row; anterior notopodial lobes fused anteriorly and seen as one tori; MGSP distinct in the transition between thorax and abdomen by dark green rings on chaetiger 11 and 12 with two rings each......................................................... Notomastus nr. latericeus