Kinnecaris linel, Karanovic & Cooper, 2011

Karanovic, Tomislav & Cooper, Steven J. B., 2011, Molecular and morphological evidence for short range endemism in the Kinnecaris solitaria complex (Copepoda: Parastenocarididae), with descriptions of seven new species 3026, Zootaxa 3026 (1), pp. 1-64 : 29-35

publication ID	https://doi.org/ 10.11646/zootaxa.3026.1.1
DOI	https://doi.org/10.5281/zenodo.5285531
persistent identifier	https://treatment.plazi.org/id/03924C3A-FFB8-A632-FF41-FA9AAA7EF8FD
treatment provided by	Felipe
scientific name	Kinnecaris linel
status	sp. nov.

Treatment

Kinnecaris linel sp. nov.

( Figs. 11–14 View FIGURE 11 View FIGURE 12 View FIGURE 13 View FIGURE 14 )

Type locality. Australia, Western Australia, Yilgarn region, Yeelirrie pastoral station, bore line L, Snake Well , 27.3074˚ S 120.1505977 ˚E.

Type material. Holotype male dissected on one slide ( WAM C47188); allotype female dissected on one slide ( WAM C47189); one paratype male and one paratype female on one SEM stub in toto coated with carbon ( WAM C47190); one paratype male dissected on one slide ( WAM C47191); one paratype female dissected on one slide ( WAM C47192); one paratype female destroyed for DNA sequence (amplification successful; see Fig. 23 View FIGURE 23 ); 10 paratypes (six males + two females + two copepodids) in alcohol ( WAM C47193); all collected at type locality, leg. T. Karanovic & S. Callan, 18 March 2010, seLN8310.

Other material examined. One female destroyed for DNA sequence (amplification unsuccessful); 10 males + 19 females + 12 copepodids in alcohol; Australia, Western Australia, Yilgarn region, Yeelirrie pastoral station, bore line L, bore L-UNK1, 27.329832˚ S 120.15059 ˚E, leg. T. Karanovic & G. Perina, 16 March 2010, seLN8533 .

Eleven males + 16 females + 12 copepodids in alcohol; Australia, Western Australia, Yilgarn region, Yeelirrie pastoral station, bore line L, bore L-UNK1, 27.329832˚ S 120.15059 ˚E, leg. T. Karanovic & S. Callan, 18 March 2010, seLN7139 .

One female destroyed for DNA sequence (amplification successful; see Fig. 23 View FIGURE 23 ); one female in alcohol; Australia, Western Australia, Yilgarn region, Yeelirrie pastoral station, bore line L, bore L-UNK1, 27.329832˚ S 120.15059 ˚E, leg. P. Bell & G. Perina, 14 November 2009, seLN7315 .

Description. Male (based on holotype and several paratypes). Total body length from 365 to 424 µm (424 µm in holotype). Surface of integument of all somites with dense and shallow cuticular pits, and all somites after cephalothorax with numerous short rows of minute spinules; third and fourth urosomites with some additional large spinules ventrally or laterally. Colour, nauplius eye, rostrum, body segmentation, and pore and sensilla pattern of all somites as in Kinnecaris esbe (see above), as well as many other details listed below. Habitus ( Fig. 11A View FIGURE 11 ) cylindrical and very slender, without any demarcation between prosome and urosome dorsally, but with urosome wider in lateral view; prosome/urosome ratio about 0.6; greatest width from dorsal view hard to establish. Body length/width ratio about 9.6; cephalothorax only slightly wider than genital somite in dorsal view. Integument strongly sclerotized as in K. esbe , and more strongly than in K.lakewayi and K. barrambie , and also with deep and irregular depressions on all somites but especially on cephalothoracic shield, and pleuras and tergites of three free prosomites. Cephalothorax with clearly visible ( Fig. 11A View FIGURE 11 ) double dorsal cuticular window posteriorly; fourth and fifth urosomites with pair of lateral circular windows each, both clearly visible and one on fifth urosomite slightly larger than that on fourth urosomite ( Fig. 11A View FIGURE 11 ).

Cephalothorax ( Fig. 11A View FIGURE 11 ) about 1.7 times as long as wide in dorsal view; representing about 18% of total body length. Surface of cephalic shield ornamented as in K. esbe , as well as tergites and pleuras of free pedigerous somites; except for additional dorsal pore on fourth and fifth pedigerous somites.

Genital somite ( Fig. 11A View FIGURE 11 ) ornamented with numerous short dorsolateral rows of spinules, in addition to three pairs of sensilla on posterior margin, and one pair of very small ventro-lateral cuticular pores in anterior part; no large spinules on this somite; spermatophore visible inside some paratypes and similar size and shape to that in K. esbe .

Third urosomite ( Fig. 11A View FIGURE 11 ) ornamented with two dorso-lateral rows of large spinules in anterior half, six posterior sensilla, and many rows of minute spinules.

Fourth urosomite ( Fig. 11A View FIGURE 11 ) ornamented with two ventro-lateral short rows of large spinules ventrally of large and somewhat swollen lateral cuticular window; additionally ornamented with six posterior sensilla and numerous minute spinules.

Fifth (preanal) urosomite ( Fig. 11A View FIGURE 11 ) with even larger and more swollen windows than those on fourth urosomite but without any large spinules, sensilla or pores; only ornamentation shallow cuticular pits and numerous minute spinules, forming nearly continuous row along hyaline fringe.

Anal somite ( Fig. 11A View FIGURE 11 ) ornamented with pair of large dorsal sensilla at base of anal operculum, pair of large cuticular pores laterally in anterior half, two pairs of minute cuticular pores laterally closer to posterior margin, and pair of slightly larger cuticular pores ventrally, at base of caudal rami, in addition to cuticular pits and rows of minute spinules. Anal operculum better developed than in K. esbe , unornamented on outer surface, ornamented with row of slender spinules on inner surface, with highly convex and smooth distal margin, not reaching posterior end of anal somite, representing 68% of somite width. Anal sinus widely opened, with two diagonal rows of slender spinules on ventral side and transverse row of spinules on dorsal side.

Caudal rami ( Fig. 11A View FIGURE 11 ) about 5.5 times as long as greatest width and 1.2 times as long as anal somite, very cylindrical in all views, with only slight inflation around insertion of dorsal seta, nearly parallel, with space between them about 1.7 times one ramus width. Armature and ornamentation as in K. esbe , but because rami slightly less elongated position of dorsal and lateral setae and their relative lengths differs. Dorsal seta inserted closer to inner margin at about 3/5 of ramus length, 0.8 times as long as caudal ramus, triarticulate basally and smooth. Lateral setae also thin and smooth, inserted close to each other at 5/6 of ramus length; proximal seta which inserted closer to dorsal surface strongest and longest, about 0.2 times as long as ramus, twice as long as proximal seta which inserted closer to ventral side, and about 1.2 times as long distal lateral seta. Inner apical seta smooth and slender, inserted closer to ventral surface, about 0.32 times as long as ramus. Middle apical seta strongest, inserted distally, without breaking plane, smooth, slightly curled, about 2.1 times as long as outer apical seta and 0.2 times as long as whole body. Outer apical seta also strong and without breaking plane, but unipinnate distally and inserted closer to ventral side than middle apical seta, about 0.85 times as long as ramus.

Antennula ( Fig. 13C View FIGURE 13 ), antenna, mouth appendages, and first two pairs of swimming legs as in K. esbe .

Third swimming leg ( Fig. 13A View FIGURE 13 ) also very similar to that in K. esbe but apophysis proportionately larger and with much more incised apical notch; longitudinal row of large spinules on outer margin also missing as in K. esbe ; exopodal spine about 1.2 times as long as apophysis.

Fourth swimming leg ( Fig. 13B View FIGURE 13 ) with five small spinules on basis at base of endopod (but not very close to it), and endopod with seven (on right leg) or nine (on left leg) large spinules arranged into scoop-like structure. Apical seta on third exopodal segment 1.3 times as long as entire exopod and 3.4 times as long as outer spine.

Fifth and sixth legs without any difference from those in K. esbe .

Female (based on allotype and several paratypes). Body length from 369 to 418 µm (408 µm in allotype). Habitus ( Fig. 14A View FIGURE 14 ), ornamentation of cephalothorax ( Fig. 12A View FIGURE 12 ) and free prosomites ( Fig. 14A View FIGURE 14 ), colour, and nauplius eye similar to those in male, except genital and first abdominal somite fused into double-somite and middle part slightly less slender. Prosome/urosome ratio 0.68; greatest width from dorsal view hard to establish; body length/width ratio 8.1; cephalothorax only slightly wider than genital double-somite.

Genital double-somite ( Fig. 11B, C View FIGURE 11 ) slightly longer than wide, without any trace of subdivision except for pair of ancestral dorso-lateral sensilla at middle; additionally ornamented with six posterior sensilla (two dorsal, two ventral and two lateral), several dorso-lateral rows of minute spinules, and one lateral short row of five large spinules in posterior half (arrowed in Fig. 11B View FIGURE 11 ), homologous to those on third urosomite in male. Genital complex ( Figs. 11C View FIGURE 11 , 14D View FIGURE 14 ) as in K. esbe .

Third urosomite ( Figs. 11B, C View FIGURE 11 , 14A View FIGURE 14 ) similar to that in male, with two groups of four large spinules ventro-laterally; lateral cuticular windows well developed and highly visible.

Fourth (preanal), and fifth (anal) urosomites also very similar to those in male ( Figs. 11A, B, C View FIGURE 11 , 14A, B View FIGURE 14 ), without any large spinules except those inside anal sinus.

Caudal rami ( Figs. 11A, B, C View FIGURE 11 , 14B View FIGURE 14 ) similar to those in male, but slightly inflated at middle in ventral view (arrowed in Fig. 11C View FIGURE 11 ) and more divergent; shorter than in previous species.

Antennula ( Fig. 12B View FIGURE 12 ) very similar to that in K. esbe , only with somewhat more robust apical aesthetasc on seventh segment.

Antenna ( Figs. 12C View FIGURE 12 , 14C, E View FIGURE 14 ) very similar to that in K. esbe , exopodal seta twice as long as segment.

Maxilla ( Fig. 12D View FIGURE 12 ) with three setae on distal endite of syncoxa, two smooth and with pore on tip, third with brush of spinules distally and strong; otherwise as in K. lakewayi .

Maxilliped ( Fig. 12E View FIGURE 12 ) with several minute spinules at base of endopod, otherwise as in K. lakewayi .

Other mouth appendages ( Fig. 14C View FIGURE 14 ), first swimming leg ( Fig. 14A, C View FIGURE 14 ), second swimming leg ( Fig. 12F, G View FIGURE 12 ), and exopod of fourth swimming leg ( Fig. 12I View FIGURE 12 ) very similar to those in male and without any difference from those in K. esbe .

Endopod of second swimming leg ( Fig. 12F, G View FIGURE 12 ), cylindrical, six times as long as wide, its apical seta 0.67 times as long as segment; one aberrant endopod in allotype inflated (arrowed in Fig. 12F View FIGURE 12 ).

Third swimming leg ( Fig. 12H View FIGURE 12 ) similar to that in K.esbe , but with more spinules along distal inner margin of endopod (arrowed in Fig. 12H View FIGURE 12 ), which also longer.

Endopod of fourth swimming leg ( Fig. 10I, J View FIGURE 10 ), small and slender, about seven times as long as wide, less than half as long as first exopodal segment, armed with single bipinnate seta apically; ornamented with several slender spinules along distal margin, at base of apical seta. Exopod similar to that in male.

Fifth leg ( Figs. 11B View FIGURE 11 , 14D View FIGURE 14 ) as in male, and without any difference from that in K. esbe ; cuticular window also not observable under light microscope.

Sixth leg ( Figs. 11C View FIGURE 11 , 14D View FIGURE 14 ) vestigial, both fused into simple bilobate cuticular plate, covering gonopore, unornamented and unarmed; outer distal corners not produced into sharp processes, but well rounded and shorter than inner lobes.

Etymology. The species name comes from its type locality (line L; see Fig. 24 View FIGURE 24 ), but should be treated as comprising an arbitrary combination of letters that can be treated as a Latin word and may be conceived as a noun in apposition to the generic name.

Variability. Body length in males ranges from 365 to 424 µm (398 µm average; n = 30), while in females it ranges from 369 to 418 µm (395 µm average; n = 42). Endopod of the female second swimming leg is always cylindrical, except in one leg in the allotype female, which is inflated at middle (arrowed in Fig. 12F View FIGURE 12 ). Endopod of the female fourth leg is always small and very slender ( Fig. 12I, J View FIGURE 12 ), and endopods of the male fourth leg always have seven spinules on the right leg ( Fig. 13B View FIGURE 13 ) and nine on the left, which is an unusual asymmetry, but it seems to be a constant character also in K. esbe . The shape of the apophysis of the male third leg ( Fig. 13A View FIGURE 13 ) is not variable, and is a very good morphological character, as are the groups of large spinules on the female urosome ( Fig. 11B, C View FIGURE 11 ).

Remarks. Morphology of this species is such that it is very hard indeed to find enough distinguishing characters between it and K. uranusi sp. nov. (see below), yet our molecular data do not support their sister-species relationship (see further below; Fig. 23 View FIGURE 23 ). Some of the most important differences include the length and shape of the caudal rami (slightly longer and more cylindrical in K. linel sp. nov.; arrowed in Fig. 11C View FIGURE 11 ), fine ornamentation of urosomites (more rows of minute spinules in K. linel , especially dorsally on anal somite; Fig. 11A View FIGURE 11 ), as well as the shape of the third leg apophysis in male (with deep apical notch in K. linel ; Fig. 13A View FIGURE 13 ). As remarked above, both species are also very similar to K. esbe sp. nov., but differ in the ornamentation of the genital double-somite in female, length of the caudal rami, and some other minor details in proportion of certain armature elements and ornamentation of appendages. Molecular data suggest a sister relationship of K. linel and K. lined sp. nov., although support for this clade is not very strong ( Fig. 23 View FIGURE 23 ). The two species, however, differ not only in the proportion of the caudal rami and ornamentation of urosomites, but also in the armature of the fourth leg basis and exopod in male, as well as in the third leg apophysis (see below).