Simplisetia qeshmensis, Bonyadi-Naeini, Alieh, Rastegar-Pouyani, Nasrullah, Rastegar-Pouyani, Eskandar, Glasby, Christopher J. & Rahimian, Hassan, 2017

Bonyadi-Naeini, Alieh, Rastegar-Pouyani, Nasrullah, Rastegar-Pouyani, Eskandar, Glasby, Christopher J. & Rahimian, Hassan, 2017, Nereididae (Annelida: Phyllodocida) of the Persian Gulf and Gulf of Oman, including description of two new species and 11 new records, Zootaxa 4244 (1), pp. 91-117 : 107-111

Simplisetia qeshmensis sp. nov.

( Figs. 5 A–D , 6 A&B , 7 A–I , 8 A–H)

Material examined. Holotype, Qeshm Island-Fajr Jetty (26° 58' 52.12" N, 56° 13' 56.68" E), intertidal zone, Sandy- cobble beach, Collector Bonyadi Naeini. A., 26 June 2015, ZUTC 6167 .

Etymology. The species name refers to the type locality.

Description. Anterior part of body 48 mm in length, with about 106 chaetigers, 2.2 mm in width. Posterior part of body missing. Color in alcohol creamy yellow with brown pigmentation on prostomium and anterior chaetigers. Prostomium wider than long. Median groove extending from anterior margin to anterior pair of eyes ( Figs. 5 A , 6 A ). Antennae slightly shorter than palps. Longest tentacular cirri reaching to chaetiger 7– 8. Pharynx everted, jaws light yellow, transparent, 4–6 sharp teeth. Maxillary ring with light brown, small cones and larger dark brown cones with light brown bases, arranged as follows: Area I =18 small cones; II = triangular clusters of 18–19, extending towards Areas I and IV and compact at base, III = 36 in scattered clusters; IV = 27–31 in triangular cluster extending towards Areas II and III ( Figs. 5 A&B , 6 A&B ). The first (apodous) segment short ( Fig. 6 A&B ). Notopodia with two similar-sized conical ligules ( Fig. 6 C), shorter than dorsal cirri in anterior chaetigers; superior ones markedly elongate becoming longer than dorsal cirri on posterior chaetigers ( Fig. 5 D ). Acicular process absent. Dorsal cirri single. Neuropodia with two ligules. Acicular neuropodial ligule present, slightly produced as low ridge on base of ventral neuropodial ligule in anterior chaetigers, reduced in middle chaetigers and disappearing in posterior chaetigers. Postchaetal lobe present, digitiform anteriorly but reduced posteriorly. Ventral neuropodial ligule of anterior chaetigers present, longer than dorsal neuropodial ligule but on posterior chaetigers reduced relative to dorsal neuropodial lobe. Ventral cirri single. Ventral cirri approximately as long as neuropodial acicular ligule. Parapodium from chaetiger 10: Neurochaetae dorsal fascicle are homogomph spinigers ( Fig. 7 A ) and short bladed heterogomph falcigers ( Fig. 7 B ); ventral fascicle are heterogomph spinigers ( Fig. 7 C&D ) and heterogomph falcigers. Parapodium from chaetiger 24: Neurochaetae dorsal fascicle are homogomph spinigers and giant simple falcigers, yellow-brown with bluntly hooked, knob-like main fang, without any tendon or any teeth. Ventral fascicle heterogomph spinigers, heterogomph falcigers, falcigers with short blades. Posterior parapodia: Neurochaetae dorsal fascicle homogomph spinigers ( Fig. 7 G ) and giant simple falcigers, yellow-brown, from chaetiger 24, with bluntly hooked, knob-like main fang, without any tendon or any teeth ( Figs. 8 E, 7 H). Ventral fascicle homogomph spinigers, heterogomph spinigers ( Fig. 7 I ), heterogomph falcigers, falcigers with short blades ( Fig. 7 E&F ).

Remarks. The material studied here resembles Simplisetia erythraeensis Fauvel, 1918 , in the presence of simple neuropodial falcigers; however, it differs in the number of paragnaths, in the type of chaeta in the ventral neuropodial fascicle, and in the form of notopodial ligule in posterior parapodia ( Table 4). The material studied here has more conical paragnaths in Area I (17–18 vs 2–6) than Fauvel᾿s material. Also, S. erythraeensis , has only two forms of chaetae in the ventral neuropodial fascicle: heterogomph spinigers and heterogomph falcigers. By contrast the material studied here has in addition homogomph spinigers in the ventral neuropodial fascicle of posterior parapodia. Homogomph spinigers are absent in the ventral neuropodial fascicle of posterior parapodia in other Simplisetia species, except for S. aequisetis . The dorsal notopodial ligule is reduced in posterior chaetigers in the studied material, which is not the case in S. erythraeensis . The studied material is similar to Composetia keiskama in having a reduced dorsal lobe of posterior parapodia. But, according to Day (1953) C. keiskama has no paragnaths in Area I and also lacks the enlarged simple chaetae as do other members of the genus. Consequently, several important characteristics are different in aforementioned species. Eight species of Simplisetia occur in the Indo-Pacific from which S. erythraeensis is the only species being recorded from the Indian Ocean. The form of the simple neuropodial falcigers differ in all Simplisetia species, in having several small teeth above the main fang or with a well-developed tendon ( Figs. 8 A, C, D, F, G, H). Sometimes small teeth or a tendon are absent ( Fig. 8 B). By comparison among the nine Simplisetia species, only S. erythraeensis and the new species described here have simple neuropodial falcigers lacking teeth or a tendon ( Fig. 8 E). More differences between selected characters in Simplisetia species are shown in Table 4.

Species name Simplisetia aequisetis (Augener, Simplisetia amphidonta (Hutchings Simplisetia erythraeensis (Fauvel Simplisetia limnetica (Hutchings &

1913) & Turvey, 1982) 1918) Glasby, 1985)

Prostomium form Prostomium wiđth about equal to Prostomium slightly longer than Prostomium wiđer than long Prostomium wiđth approximately length wiđe, with đeep anteromeđian equal to length, with đeep međial groove groove extenđing from near tip to between anterior pair of eyes

Paragnath shape Paragnaths brown, triangular cones, Grey-brown, transparent đomes anđ Paragnathes small conical, acute, Brown cones slight variation in size large, sharply pointeđ, elongate đark brown, very fine

cones, opaque, orange to scarlet

with grey-brown bases

Numbers anđ pattern of paragnaths 4)8 cones in an irregular patch Central patch of 9 đomes anđ 2 large 2 to 6 very small cones 1)5 cones

Area I starlet cones on either siđe

Numbers anđ pattern of paragnaths An oblique group of 25)32 8 in irregular oblique rows of brown triangular clusters extenđing over 15) 30 in oblique banđ

Area II đomes siđes

Numbers anđ pattern of paragnaths Broađ transverse patch of 5)7 19 in transverse banđ of 10 đomes Cross cluster several rows 26) 43 in broađ transverse banđ

Area III irregular rows, consisting of 53)58 anđ 9 large scarlet cones

cones

Numbers anđ pattern of paragnaths Reverse Y shapeđ crescent mađe of 15)17 đomes in triangular patch Triangular cluster, angles extenđing 20) 43 in V or Y-shapeđ banđ

Area IV 38)43 cones towarđ II anđ III

Neuropođial postchaetal lobe Absent Present Absent Present

anteriorly

Ventral neuropođial lobe anteriorly Conical, ređuceđ to a small tubercle Well-đevelopeđ (đigitiform) but Slightly ređuceđ Well đevelopeđ, ređuceđ to a small by chaetigers 20)29 đecreasing rapiđly to đisappear by tubercle by about chaetiger 25 miđđle chaetigers

Ventral neuropođial lobe Small tubercles Absent No Data Increasing in size relative to other posteriorly lobes posteriorly Fully formeđ giant simple falcigers Poorly đevelopeđ teeth above main 1 or 2 đistally đark, strongly hookeđ Main fang smooth 1 or two bluntly hookeđ with a fang with several small teeth above main đistinct tenđon variable in shape, fang sometimes with 3)4 minute teeth proximal to main fang, but most often smooth Ventral fascicle neuropođial Present Absent Absent Absent

homogomph spiniger posteriorly

Neuropođial heterogomph falcigers Present Present Present Present anteriorly anđ at the miđ bođy but absent posteriorly

……continued on the next page Species name Simplisetia lizardensis (Ben Simplisetia qeshmensis sp. Simplisetia transversa Simplisetia turveyi Simplisetia vaipekae (Gibbs,

Eliahu et al., 1984) nov ( Hutchings & Turvey, 1982) ( Hutchings & Glasby, 1982) 1972)

Prostomium form Prostomium length Prostomium wiđer than long Prostomium length about Prostomium length about No Data

aproximately equal to wiđth equal to wiđth with đeep equal to wiđth, with a đeep međial groove anteromeđian groove shallow međial groove extenđing from anterior extenđing from near tip to margin to wailer pair of eyes level with base of palps

Paragnath shape No đata Light brown cones anđ larger Pale-đark brown cones Light brown cones anđ larger No Data

ones, đark brown cones with đark brown cones with light light brown bases brown bases

Numbers anđ pattern of 1)2 cones 18 very small cones No cones 0)5 cones No Data

paragnaths in Area I

Numbers anđ pattern of 13)17 triangular clusters of 18)19, 6 in transverse line of large 14 in 2 rows on right anđ No Data

paragnaths in Area II extenđing over siđes anđ anđ small cones triangular patch on left compact at the base

Numbers anđ pattern of 7)31 transverse banđ 3 rows 36 in scatteređ clusters Absent 7 in transverse line No Data

paragnaths in Area III đeep

Numbers anđ pattern of 17)23 27) 31 in triangular cluster 7 in transverse line of large 15 in V)shapeđ banđ

paragnaths in Area IV extenđing over siđes to II anđ anđ small cones

III.

Neuropođial postchaetal lobe Present (well-đevelopeđ) Present Present (well-đevelopeđ) Absent Absent

anteriorly

Ventral neuropođial lobe Present but, ređuceđ relative Present, longer than in length Conical, well đevelopeđ a, Present, ređuceđ to small Present

anteriorly to đorsal lobe. from miđ- to đorsal neuropođial ligule điminishing rapiđly to be tubercle from about chaetiger bođy absent by miđđle chaetigers 30 onwarđs

Ventral neuropođial lobe Absent Ređuceđ relative to đorsal Absent Absent Ređuceđ posteriorly but, still

posteriorly neuropođial lobe remains as a well-đevelopeđ

lobe

formeđ giant simple Bluntly hookeđ, knob-like tip Main fang smooth without Strongly hookeđ with several With an inđistinct tenđon anđ A conical main fang with

falcigers connecteđ to shaft by đistinct any tenđon small teeth above main fang, 3 small teeth proximal to rows of small teeth above, tenđon, few teeth đistal to đark đistally, without tenđon bluntly conical main tooth with well-đevelopeđ tenđon knob

Ventral fascicle neuropođial Absent Present Absent Absent No Data

homogomph spiniger

posteriorly

Neuropođial heterogomph Present Present Present Present Present falcigers

Figures

FIGURE 5. A – D. Simplisetia qeshmensis sp. nov., A: Dorsal view of everted proboscis. B: Ventral view of everted proboscis. C: Parapodium Chaetiger 10, anterior view. D: Posterior parapodium, anterior view.

FIGURE 6. A – B. Simplisetia qeshmensis sp. nov., A: Dorsal view of anterior part of body. B: Ventral view of anterior part of body.

FIGURE 7. A – I. Simplisetia qeshmensis sp. nov., A: Dorsal fascicle neuropodial homogomph spiniger, chaetiger 10. B: Dorsal fascicle neuropodial heterogomph falciger, chaetiger 10. C & D: Ventral fascicle neuropodial heterogomph spiniger, chaetiger 10. E & F: Ventral fascicle neuropodial heterogomph falciger, posterior chaetiger. G: Dorsal fascicle neuropodial homogomph spiniger, posterior chaetiger. H: Dorsal fascicle neuropodial giant simple falciger, posterior chaetiger. I: ventral fascicle neuropodial heterogomph spiniger, posterior chaetiger.

FIGURE 8. Illustrations of different simple neuropodial falcigers in Simplisetia species, A: S. lizardensis; B: S. erythraeensis; C: S. limnetica; D: S. turveyi; E: S. qeshmensi s sp. nov.; F: S. aequisetis; G: S. transversa; H: S. amphidonta. (A, B, C, D, F, G, H with modifications from A; Ben-Eliahu et al. (1984), B; Fauvel (1918), C, D, G & H; Hutchings & Turvey (1982), F; Hutchings & Glasby (1985), respectively).