Rostrocalanidae Family - Marine Planktonic Copepods

Calanoida ( Order )	details
Clausocalanoidea ( Superfamily )	details

Abbreviations or symbols

Rostrocalanidae Markhaseva, Schulz & Martinez Arbizu, 2008 ( Clausocalanoidea )

Ref.:

Markhaseva & al., 2008 (p.2421); Markhaseva & al., 2014 (p.63, 67, 77, Table 1, 2, 3, 4, Rem., Def.); Laakmann & al., 2019 (p.330, Table 1, fig.1, 2, 3, 4, Table A, phylogenetic relationships)

Rem.:

Type genus: Rostrocalanus Markhaseva, Schulz, Martinez Arbizu, 2009. 1 G

For Markhaseva, Laakmann & Renz (2014, p.77) the diagnosis is based on the following combination of characters: the apomorphies for the family within the ''Bradfordians'' are: Md exopod 4-segmented, bearing 4 setae; Mxp praecoxal endites setal formula: 0, 1, 2, with praecoxal setae as: 0 + 1sc + 2sc; Mxp basis without distal setae.

General characters :

1 - A2 coxa without seta; basis with 1 seta; endopodal segment 1 with 1 seta; setal formula of exopod: 0, 0-1-1-1, 1, 1, 1, 0, 3.

2 - Md endopodal segment 2 with 6 setae; gnathobase with hump/crest (see table 2).

3 - Mx1 setal formula: 9, 2, 2, 5 (at fused distal basal endite and endopod), 5-6, 0 (or 3-4) (see table 3).

4 - Mx2 endites setal formula: 1-2, 3, 3, 3, 4; endopod with 6 worm-like sensory setae (see table 4).

5 - Mxp basis with 2 proximal setae.

For Markhaseva & al. (2008, p.2438) Rostrocalanus could be considered an early offshoot of the Tharybidae lineage.
Markhaseva & al. (2014, p.77) note that this genus shows a similarity to Brodskius Markhaseva & Ferrari, 2005; Undinella Sars, 1900 and some species of Tharybis, since the coxa of A2 lacks a seta. Rostrocalanus shares with some species of Ubdibella and Parkius 2 proximal setae at the Mxp basis, and with Brodskius, Bradfirduiella Andronov (2007) and some species of Rythabis Schulz (1995) a fused distal endite and endopod of the Mx1 (see Table 1, 3 and 5).

Issued from : E.L. Markhaseva, S. Laakmann & J. Renz in Mar. Biodiv., 2014, 44 [p.73, Table I].
A2 armament (number of seta) in different ''Bradfordian'' genera (females). Rostrocalanidae.
c: coxa; b: basis; End 1: endopod segment 1; End 2: endopod segment 2; Exp: exopod.

Issued from : E.L. Markhaseva, S. Laakmann & J. Renz in Mar. Biodiv., 2014, 44 [p.74, Table 2].
Md armament (number of seta) in different ''Bradfordian'' genera (females). Rostrocalanidae.
b, basis; End 1: endopod segment 1; End 2: endopod segment 2; Exp: exopod; gn: gnathobase.

Issued from : E.L. Markhaseva, S. Laakmann & J. Renz in Mar. Biodiv., 2014, 44 [p.76, Table 3].
Mx1 armament (number of seta) in different ''Bradfordian'' genera (females). Rostrocalanidae.
pa: praecoxal arthrite (setal formula : terminal+posterior+anterior setae); ce: coxal endite; bp: proximal basal endite; bd: distal basal endite; End: endopod; Exp: exopod; Epi: epipodite.

Issued from : E.L. Markhaseva, S. Laakmann & J. Renz in Mar. Biodiv., 2014, 44 [p.78, Table 4].
Mx2 armament (number of seta) in different ''Bradfordian'' genara (females). Rostrocalanidae.
at: attenuation; pe: praecoxal endite; ce: coxal endite; bp: proximal basal endite; bd: distal basl endite; el: enditic-like lobe of proximal endopodal segment; End: endopod; w, worm-like seta; br: brush-like seta; sc: sclerotised seta.

Issued from : E.L. Markhaseva, S. Laakmann & J. Renz in Mar. Biodiv., 2014, 44 [p.80, Table 5].
Mxp setation (number of seta) in different ''Bradfordian'' genera (females). Rostrocalanidae.
at: attenuation; pes: praecoxal endites of syncoxa (from proximal to distal); ces: coxal endite of syncoxa; bp: basis proximal; bd: basis distal; End: endopodal segments 1 to 5.
For more detailed morphology of the setae on the praecoxal endites of the Mxp syncoxa see markhaseva & Ferrari (2005) and Markhaseva & al. (2008).

Issued from : S. Laakmann, E.L. Markhaseva & J. Renz in Mol. Phylog. Evol., 2019, 130. [p.331, Table 1].
compilation of information on relationships among ''Bradfodian'' genera from Markhaseva & Ferrari 2005) and Markhaseva & al. (2014).
Abbreviations: A2, antenna; Md, mandible; Mx1, maxillule; Mx2, maxilla; Mxp, maxilliped ; P5, leg 5. w, worm-like sensory seta; b, brush-like sensory seta; s, sclerotized seta.;

(1) Rostrocalanus Markhaseva, Schulz & Martinez Arbizu, 2008

Species, varieties and details

Ref.:

Markhaseva & al., 2008 (p.2421); Markhaseva & Renz, 2011 (p.68, Rem.); Renz & Markhaseva, 2015 (p.96, Table 4, Fig.3, biogeography); Laakmann & al., 2019 (p.330, Table 1)

Rem.:

Type: Rostrocalanus peracutus. Total: 2 spp.

Diagnosis from Markhaseva & al; (2008, p.2421):
Female:
- Cephalosome and 1st pediger fused, 4th and 5th incompletely separate.
- Rostrum large, as rounded plate without filaments.
- Prosome 3.4-5.1 times longer than urosome.
- Posterior corners of prosome prolonged and obtusely rounded or acutely pointed.
- A1 24-segmented.
- A2 coxa without seta; basis with 1 small vestigial seta; endopodal segment 1 with 1 seta; exopod 7-segmented with 0, 3, 1, 1, 1, 0 and 3 setae.
- Gnathobase of Md with keel, cutting edge bearing 4 to 5 teeth, 1 fork-like distally and tipped with 3 to 4 points; endopodal segment 1 without seta, endopodal segment 2 with 6 setae; basis with 2 setae, one very small; exopod 4-segmented with 1, 1, 1 and 1 setae.
- Praecoxal endite of Mx1 with 9 terminal elements, four or five of them as thick spines, other setae modified (with swollen headsà or not; coxal endite with 2 setae, coxal epipodite with 3 to 4 setae, or setae absent; proximal basal endite with 2 setae; distal basal endite fused to endopod, with 5 setae ( setal affiliation obscure); exopod with 5 or 6 setae.
- Proximal praecoxal endite of Mx2 with 1 or 2 setal elements, distal with 3 setae; proximal and distal coxal endites with 3 setae each; proximal basal endite with 4 setae; endopod apparently 3-segmented, with 6 long and slender worm-like sensory setae.
- Syncoxa of Mxp without seta on proximal praecoxal endite, with 1 seta on middle endite and 2 setae on distal praecoxal endite; coxal endite bearing 2 setae. Setae of praecoxal endites poorly sclerotized but not aesthetasc-like; basis with 2 medial setae, distal setae absent; endopod 5-segmented with 3, 2, 2, 3+1, 4 setae.
- P1 basis with or without medial distal seta; lateral lobe of endopod moderately developed.
- P5 uniramous, 2-segmented; distal segment with 3 spine-like unarticulated extensions terminally.

Males unknown.

Remarks on dimensions and sex ratio:

The mean female size is 1.550 mm (n = 4; SD = 0.3240). Male unknown.