Nullosetigeridae Family - Marine Planktonic Copepods

Calanoida ( Order )	details
Arietelloidea ( Superfamily )	details

Abbreviations or symbols

Nullosetigeridae Soh, Ohtsuka, Imabayashi & Suh, 1999 ( Arietelloidea )

Syn.:

Phyllopinae Brodsky, 1950 (1967) (p.398); Brodsky & al., 1983 (p.143).
Phyllopidae : Campaner, 1977 (p.811, 817, Rev.); Björnberg & al., 1981 (p.650); Razouls, 1982 (p.532); Mauchline; 1988 (p.706); Bradford-Grieve & al., 1999 (p.884, 902, 903, 949); Bradford-Grieve,1999 b (p.126, Def.); Phyllopodidae Bowman & Abele, 1982 (p.9, emend.); Huys & Boxshall, 1991 (p.419); Razouls, 1993 (p.307); Chihara & Murano, 1997 (p.862)

Ref.:

Soh & al., 1999 (p.1581); Ohtsuka & Huys, 2001 (p.461); Boxshall & Halsey, 2004 (p.14; 49; 148: Def.); Vives & Shmeleva, 2007 (p.385); Blanco-Bercial & al., 2011 (p.103, Table 1, Fig.2, 3, 4, Biol. mol, phylogeny); Laakmann & al., 2019 (p.330, fig. 2, 3, phylogenetic relationships)
Bradford-Grieve J.M., (2002 onwards). Key to calanoid copepod families. Version 1 : 2 oct 2002. http://www.crustacea.net/crustace/calanoida/index.htm

Rem.:

Type-genus: Nullosetigera Soh, Ohsuska, Imbayashi & Suh, 1999. 1 G..
Boxshall & Halsey (2004, p.150) note that the Nullosetigeridae (as the Phyllopodidae) was included in the superfamily Arietelloidea (as Augaptiloidea) by Bowman & Abele (1982) and Park (1986). Brodsky (1980) erected a new subfamily, the Phyllopinae, within the Arietellidae to accomodate the genus Phyllopus. Campaner (1977) redefined the Arietellidae and raised the Phyllopinae to a separate family on the basis of the characters: a well developed endopod on the mandibular palp, the form of the maxillule, the armarture of the maxillary basis, the relative lengths of the maxillipedal segments, and the form of the fifth legs.

Diagnosis from Boxshall & Halsey (2004, p.148) :
- Broad prosome and slender urosome.
- Prosome 5-segmented comprising cephalosome, 3 free pedigerous, and double-somite comprising fused 4th and 5th pedigerous somites.
- Posterolateral corners of prosome rounded or expanded and produced in female, asymmetrical in some species.
- Urosome 4-segmented in female; with 3 free abdominal somites. Genital double-somite symmetrical or asymmetrical, with paired copulatory pores apparently paired and located within paired, separate genital apertures.
- Urosome 5-segmented in male, comprising genital somite and 4 free abdominal somites. Single genital, aperture located ventrolaterally at posterior rim of genital somite on right side.
- Caudal rami with 6 setae; inner terminal seta V on right side much longer than counterpart on left side, in some species.
- Rostrum divided into paired rostral spines.
- Nauplius eye absent.
- A1 24-segmented in female, asymmetrical, with right A1 slightly longer than left. Segmental homologies: segment 1 (I-III) triple, segments 2 (IV) to 23 (XXV) separate, apical (24th) segment triple (XXVI-XXVIII); aesthetascs usually present on segment I, III to XXI, XXV and XXVI-XXVIII.
- A1 male 20-segmented, geniculate on left side only. Segmental fusions: I-IV, XXI-XXIII, XXIV-XXV and XXVI-XXVIII.
- A2 biramous; coxa and basis separate; coxa with 0/1 seta; basis with 2 setae; endopod 2-segmented, 1st segment with 1 seta, compound distal segment bilobed, armed with 7 and 6 setae on inner and outer lobes; exopod 8-segmented, setation formula: 0, 0, 1, 1, 1, 1, 1, 3.
- Labrum large, very broad, ornamented with spinule rows posteriorly.
- Md with well developed coxal gnathobase; palp consisting of unarmed basis, 2-segmented endopod and 5-segmented exopod. Endopodal segments 1 and 2 with 2 and 6 or 7 setae; exopodal setation formula: 1, 1, 1, 1, 2.
- Mx1 with powerfully developed tapering, praecoxal arthrite bearing about 16 elements along distal and dorsal margins; distal part of limb reduced; coxa with endite bearing 2 slender setae, lacking setae on epopodite; basis lacking outer seta, with minute proximal endite bearing 1 seta, distal endite represented by single seta, rarely unarmed. Endopod minute, 1-segmented, typically with 3 or 4 setae; exopod small, 1-segmented armed with 5 or 7 small setae.
- Mx2 6-segmented; praecoxa and coxa fused to form large syncoxa, setation formula of endites 3/4 (plus vestigial element), 2, 3, 3; basis with 4 setae, all distinct from segment; free endopod 4-segmented; 1st segment with 4 setae on endite, 2nd to 4th segments bearing up to 7 setae in total (3, 2, 3).
- Mxp 7-segmented ; short, stout syncoxa with endite setation formula 0 /1/2, 1/2, 1/3; basis elongate with 3 setae, plus 2 distal setae representing incorporated 1st endopodal segment, free endopod 5-segmented, segmental setation formula typixally 3/4, 4, 3, 3, 2-4.
- Swimming legs 1 to 4 biramous, with 3-segmented rami, endopods smaller than exopods. Basis of P1 elongate, with origin of exopod proximal to origin of endopod. Inner seta on basis of P1 situated on anterior surface of basis and passing across face of 1st and 2nd endopodal segments.

Diagnosis after Bradford-Grieve (1999 b, p.126) [summary]:
Female:
- Genital segment usually asymmetrical with a single genital aperture located ventrolaterally on the posterior right border.
- Caudal rami symmetrical, relatively short.
- A1 symmetrical, not extending beyond posterior border of prosome.
- A2 basis with 2 outer edge setae; endopodal segment 1 with 1 seta distal to midlength, segment 2 with 7-8 inner setae and 6 setae terminally. Exopod 8-segmented, proximal 2 segments without setae and partially fused with segment 3.
- Md gnathobase longer than palp.
- Mx1 arthrite large with 15 spines and setae; remainder of limb reduced; inner lobes 2-4 with 2, 1, 1 setae respectively; endopod 1-segmented, with 4 setae; exopod small with 7 setae; outer lobe 1 in the form of small lobe, without setae; outer lobe 2 absent.
-Mx2 well developed, lobes 1-5 with 3, 2, 3, 3, 4 setae respectively; endopod 4-segmented with 10-11 setae.
- Mxp basipod 1 short with 2 proximal, 2 medial and 1 distal setae; basipod 2 with 3 setae distally; endopod 5-6-segmented, segment 1 almost fully incorporated into basipod 2, with 2, 4, 4, 3, 1+2 setae respectively, each segment with one of the setae small or vestigial.
-
Male:
- A1 geniculate on left, 20-segmented.
- Mouthparts similar to those of female.
- P5 basipod 1 and coupler fused, basipod 2 with a long outer edge seta on each side; left leg with 1-segmented, foliaceous endopod, exopod3-segmented with last 2 segments in the form of a chela; right leg without an endopod, exopod 3-segmented, segment 2 and 3 more or less fused, segment 3 expanded and truncate distally.

Issued from : G.A. Boxshall & S.H. Halsey in An Introduction to Copepod Diversity. The Ray Society, 2004, No 166, Part. I. [p.148].
Armature formula of swimming legs P1 to P4.

- Female P5 comprising transverse plate, formed by fusion of coxae and intercoxal sclerite; basis and 3-segmented exopod; basis with outer seta; 1st exopodal segment with outer spine, 2nd exopodal segment with outer spinous process plus long inner seta, 3rd segment with multi-toothed, serrate distal margin plus inner seta.
- Male P5 asymmetrical; right leg uniramous, 5-segmented, consisting of coxa, basis bearing outer setal element, plus 3-segmented exopod, 2nd and 3rd segments somewhat flattened and incompletely fused; left leg biramous, with unsegmented, flattened endopod and 3-segmented exopod, 1st exopodal segment slender with outer spine, 2nd robust and produced into spinous distal process, 3rd segment forming slender movable spine.

Issued from : G.A. Boxshall & S.H. Halsey in An Introduction to Copepod Diversity. The Ray Society, 2004, No 166, Part. I. [p.149, Fig.32]. Nullosetigeridae.
A, Nullosetigera mutata habitus female (dorsal view) B, Nullosetigera auctiseta habitus male; C, female Mx1; D, Nullosetigera mutata female P5; E, Nullosetigera auctiseta male P5. [Soh & al., 1999]

Issued from : J.M. Bradford-Grieve in NIWA Biodiversity Memoir 111, 1999. [p.127].
Seta and spine formula of swimming legs P1 to P4.
- Female P5 uniramous, not natatory, basipod 1 and coupler fused; basipod 2 with an outer edge seta; exopod 3-segmented with I-0; 0-1; 0, 0, I spines and setae; outer and distal borders of exopodal segments 2 and 3 expanded and toothed.

- Male P5 basipod 1 and coupler fused, basipod 2 with a long outer edge seta on each side; left leg with 1-segmented, foliaceous endopod, exopod 3-segmented with last 2 segments in the form of a chela; right leg without an endopod, exopod 3-segmented, segments 2 and 3 more or less fused, segment 3 expanded and truncate distally.

(1) Nullosetigera Soh, Ohtsuka, Imabayashi & Suh, 1999

Species, varieties and details

Syn.:

Phyllopus Brady, 1883 (p.78) (nom preoc.); Giesbrecht, 1892 (p.66, 419); Giesbrecht & Schmeil, 1898 (p.124); Esterly, 1905 (p.190); Quidor, 1908 (p.3); van Breemen, 1908 a (p.142); A. Scott, 1909 (p.147); Wolfenden, 1911 (p.327); Sars, 1925 (p.340); Sewell, 1932 (p.330); Wilson, 1932 a (p.136); Rose, 1933 a (p.244, clé spp.); Brodsky, 1950 (1967) (p.399, spp. Key); Tanaka, 1964 c (p.236); Campaner, 1977 (p.811, Rem.); Razouls, 1982 (p.532); Mauchline, 1988 (p.706); Razouls, 1993 (p.307); Mauchline, 1998 (p.71: F; p.76: M); Bradford-Grieve & al., 1999 (p.884, 950: spp. Key); Bradford-Grieve,1999 b (p.127, Rem.); Boxshall & Halsey, 2004 (p.150: spp. Key)

Ref.:

Soh & al., 1999 (p.1582, 1600: key of japanese species); Boxshall & Halsey, 2004 (p.139, Déf., Clé des espèces); Vives & Shmeleva, 2007 (p.386, spp. key)

Rem.:

Total: 9 spp.
Taxonomic note from Boxshall & Halsey (2004, p.150): The name Phyllopus Brady, 1883 was preoccupied by Phyllopus Rafinesque, 1815, but Phyllopus Rafinesque was suppressed. An application to suppress Phyllopus Rafinesque for purposes of homonymy was required to preserve nomemclatural stability. This application was never made and in 1999, Soh & al. proposed the replacement generic name Nullosetigera, and the derived family name Nullosetigeridae.

Key to species (after Boxshall & Halsey (2004, p.150) (adapted from Soh, Ohtsuka, Imbayashi & Suh, 1999) :1 – P4 with inner coxal seta : male P5 with tapering process on compound transverse plate formed by intercoxal sclerite and coxae …… 2.
1’ – P4 without inner coxal seta ; male P5 without any processes on compound trnsverse plate formed by intercoxal sclerite and coxae …… 3.
2 – Coxal endite of Mx1 with 2 extremely unequal setae ; 6th endopodal segment of Mxp armed with 4 setal elements ….. N. mutica.
2’ – Coxal endite of Mx1 with 2 nearly equal setae ; 6th endopodal segment of Mxp armed with 3 setal elements ……… N. auctiseta.
3 – Female genital double-somite stymmetrical , protruding on both sides ; male left P5 without distinct demarcation between tooth and 2nd exopodal segment ; right P5 with large tongue-like process on 1st exopodal segment ….. N. impar.
3’ – Female genital-double-somite symmetrical, weakly convex on both sides, or with more or less parallel sides …… 4.
3’’ – Female genital double-somite asymmetrical : tooth on 2nd exopodal segment of male left P5 distinctly separated from 3rd exopodal segment …… 5.
4 – Posterolateral angles of prosome slightly asymmetrical ; genital double-somite less than 25% longer than wide and with convex lateral margins …… N. aequalis.
4’ – Posterolateral angles of prosome asymmetrical, markedly produced on right side ; genital double-somite more than 40% longer than wide and with parallel lateral margins ……. N. giesbrechti.
5 – Female with last pedigerous somite symmetrical ; genital double-somite protruding on right side ; 3rd exopodal segment of male left P5 very elongate ….. N. helgae.
5’ – Female with last pedigerous somite asymmetrical, with posterolateral corners modified into apically truncate lobes ; male left P5 with small distal tooth and short curved claw on 3rd exopodal segment ……. N. bidentata / N. integer.
5’’ – Female with last pedigerous somite slightly asymmetrical, with tiny spinules on posterior corners …… N. mutata.

Remarks on dimensions and sex ratio:

If we exclude the species N. mutica of which the lengths are exceptional in the genus we obtain: the mean female size is 2.828 mm (n = 13; SD = 0.5071) and the mean male size is 2.675 mm (n = 11; SD = 0.4081). The size ratio (Male : Female) is 0.922 (n = 7; SD = 0.0880). The sex ratio is 1.125 (more probably = 1)