Trypanosyllis californiensis, Álvarez-Campos & Giribet & San Martín & Rouse & Riesgo, 2017

Álvarez-Campos, Patricia, Giribet, Gonzalo, San Martín, Guillermo, Rouse, Greg W. & Riesgo, Ana, 2017, Straightening the striped chaos: systematics and evolution of Trypanosyllis and the case of its pseudocryptic type species Trypanosyllis krohnii (Annelida, Syllidae), Zoological Journal of the Linnean Society 179 (3), pp. 492-540 : 528-530

TRYPANOSYLLIS CALIFORNIENSIS

ALLVAREZ- CAMPOS & ROUSE SP. NOV.

FIGS 10H , 15D – F

Type material examined

Holotype. California: specimen in 96% EtOH ( SIO A5008 ), La Jolla, San Diego (32.866944, 117.255833), kelp holdfast, 5 m, 18 April 2014, leg. G.W. Rouse.

Paratypes. California: one specimen mounted for SEM ( SIO A5007 ), collection data as for the holotype ; two specimens in 96% EtOH ( SIO A5006 , 5009 ), La Jolla, San Diego (32.866944, 117.255833), algae, 0 m, 18 April 2014, leg. G.W. Rouse.

Diagnosis

Similar to Trypanosyllis krohnii except for pigmentation and body size ( Fig. 10H ). Dark-brown transverse stripes across anterior segments of living specimens. Fixed material appears red/pink with dark red – purple stripes: anterior stripe is situated close to anterior end of segment, whereas posterior stripe appears slightly before end of segment (anterior and posterior stripes appear as two close lines per segment, but, in fact, are on different segments; Fig. 10H ). Appendages also with pigmentation only in limit of each article.

Description

Holotype incomplete: 12 mm long, 0.8 mm wide, 76 chaetigers. Body coloration in live specimens white/ pale, with two dark-brown thin transverse stripes across anterior and midbody segments of live specimens ( Fig. 10H ). Fixed material appeared red pigmented with dark red – purple stripes. Anterior stripe situated only in anterior end of segment, whereas posterior stripe slightly precedes posterior end of segment ( Fig. 9H ). Appendages also with pigmentation in limit of each article. Oval prostomium with two pairs of red eyes in trapezoidal arrangement ( Fig. 10H ). Oval palps shorter than prostomium, completely separate. Nuchal organs not seen. Segment 1 slightly smaller than subsequent segments; antennae originating on anterior margin of prostomium, median antenna with about 20 articles; lateral antennae slightly shorter, with 15 – 17 articles. Dorsal enlarged anterior cirri longer than antennae, with about 32 articles, much longer than ventral cirri, with about 17 articles. Dorsal cirri alternating between long (30 – 32 articles) and short (20 – 22 articles). Dorsal cirri of the anteriormost segments slightly longer than the rest, with 34 – 36 articles. Ventral digitiform cirri, shorter than parapodia. Compound bidentate heterogomph falciger chaetae with spines on margin, with between eight and ten spines per parapodium ( Fig. 15D – F ), similar throughout body, except in most posterior parapodia, that are shorter ( Fig. 15F ). Two or three thick, acutely pointed aciculae in all segments. Dorsal and ventral simple chaetae not seen. Pharynx through about 14 segments, proventricle through 11 segments, with about 30 muscle cell rows.

Remarks

The examined specimens of Trypanosyllis californiensis sp. nov. collected in La Jolla differ markedly from those of Trypanosyllis luquei sp. nov., collected from San Diego Bay, in length of dorsal cirri (32 and 20 articles in the former, 20 and 14 articles the latter; four and three specimens from each species) and in coloration ( Trypanosyllis californiensis sp. nov. has stripes on each segment, whereas Trypanosyllis luquei sp. nov. has stripes in the anterior and posterior end of the segment). In addition, there are also ecological differences: Trypanosyllis californiensis sp. nov. occurs in association with algae, whereas Trypanosyllis luquei sp. nov. lives in association with bryozoans. Another congeneric species described from California (from Monterey Bay), Trypanosyllis intermedia Moore, 1909 ; differs from Trypanosyllis californiensis sp. nov. in colour pattern, which is reddish brown in the dorsum with pale in anterior and posterior ends of segments (instead of the two brown transverse stripes of Trypanosyllis californiensis sp. nov.) and also in the form of midbody and posterior chaetae, which are much shorter, bidentate, and without spines, i.e. more similar to those in Trypanedenta gemmipara comb. nov. ( Fig. 7E ).

Type locality

La Jolla, San Diego (Pacific Ocean).

Distribution

Only known from the type locality.

Etymology

Named after the state of California, where the type locality of the species is located.

Figures

Figure 7. Scanning electron micrographs of Pseudosyllis brevipennis (MNCN 16.01/16177): A, anterior part; B, midbody chaetae; C, midbody aciculae. The arrows point to the nuchal organs (no) and ciliary rows (cr).

Figure 9. Scanning electron micrographs of Trypanedenta gigantea comb. nov.: A, anterior part (MNCN 16.01/ 16505); B, prostomium (MNCN 16.01/16505), arrow points to the nuchal organs (no); C, detail of dorsal cirri (MNCN 16.01/16506); D, detail of the trepan pharynx in apical view, arrow points to the trepan (t) (MNCN 16.01/16501); E, pharynx and proventricle (MNCN 16.01/165052); F, anterior chaetae (MNCN 16.01/16505); G, midbody chaetae, arrow points to four protruding aciculae (a; MNCN 16.01/16506); H, posterior chaetae, arrow points to two protruding aciculae (a; MNCN 16.01/16508).

Figure 10. Light microscopy images of the anterior of Trypanosyllis s.s. species: A, Trypanosyllis krohnii neotype (MNCN/ADN 9623); B, Trypanosyllis aeolis (MNCN 16.01/16039); C, Trypanosyllis zebra (ZMB Q4428); D, Trypanosyllis luzonensis comb. nov. (AM W.47275); E, Trypanosyllis taboadai sp. nov. holotype (MNCN 16.01/16087); F, Trypanosyllis luquei sp. nov. holotype (SIO A5005); G, Trypanosyllis leivai sp. nov. holotype (MNCN 16.01/16082); H, Trypanosyllis californiensis sp. nov. holotype, live specimen (SIO A5008); I, Trypanosyllis sp. 2 (MNCN 16.01/ 16065); J, Trypanosyllis kalkin sp. nov. holotype (MNCN 16.01/16058).

Figure 15. Scanning electron micrographs of new species from the Trypanosyllis krohnii species complex: A–C, Trypanosyllis taboadai sp. nov. (MNCN 16.01/16078); D–F, Trypanosyllis californiensis sp. nov. (SIO 5007); G–I, Trypanosyllis leivai sp. nov. (MNCN 16.01/16073). A, D, G, anterior chaetae. B, E, H, midbody chaetae. C, F, I, posterior chaetae.