Fridericia peregrinabunda Michaelsen, 1913

(FigURES 4A–F)

Fridericia peregrinabunda Michaelsen, 1913; Schmelz 2003.

Fridericia carmichaeli Stephenson, 1915 .

Fridericia giniata Springett, 1971 .

Fridericia bulbosa (Rosa) var. [sic]. Michaelsen 1907.

Fridericia bollonsi Christoffersen, 1976 .

Examined material. XZO201510005, XZO102510006, XZO201510007, ThREE adUlT FiXEd aNd STaiNEd SPEcimENS. MORE ThaN 10 SPEcimENS PRESERVEd iN 70% EThaNOl.

Descriptions. MEdiUm SiZE. BOdY SiZE (iN ViVO): lENgTh abOUT 11.3 mm, bOdY WidTh 0.3 mm iN V, 0.4 mm iN XII. SEgmENT NUmbER 39–56. HEad PORE aT 0/I, lONgiTUdiNal SliT (Fig. 4D). ChaETaE ShORT aNd SlENdER, 2 PER bUNdlE ThROUghOUT, OccaSiONallY 3 iN SOmE POSTERiOR SEgmENTS. EPidERmal glaNd cEllS bROWN iN FEW aNTERiOR SEgmENTS, gRadUallY gRaY iN POSTERiOR SEgmENTS, 2 OR 3 ROWS PER SEgmENT. SUbNEURal glaNd abSENT. CliTEllUm aT XII–1 /2XIII, SlighTlY ElEVaTEd. BRaiN SlighTlY cONVEX aNTERiORlY, TRUNcaTE POSTERiORlY, ca. 150 Μm iN lENgTh aNd 100 Μm iN WidTh iN ViVO (Fig. 4D). SEPTa iN V/VI–VIII/IX ThickENEd (ca. 17.5 Μm iN ViVO). OESOPhagEal aPPENdagES WiTh 3–5 TERmiNal bRaNchES, EXTENdiNg iNTO V (Fig. 4B). ThREE PaiRS OF PhaRYNgEal glaNdS, all WiTh WidE dORSal cONNEcTiON. VENTRal lObES PRESENT iN all PaiRS, SmallEST iN IV, dORSal aNd VENTRal lObES iN V aNd VI OF abOUT SamE SiZE (Fig. 4C). FiVE PaiRS OF PREcliTEllaR NEPhRidia iN VI/VII–X/XI, EFFERENT dUcT RiSiNg FROm ThE middlE OF POSTSEPTalE (Fig. 4F). COElOmOcYTE–mUcOcYTES (TYPE “c’) OVal aNd NUmEROUS, ca. 50 Μm iN ViVO, lENTicYTES abUNdaNT, ca. 5–6 Μm iN ViVO (Fig. 4A). ChYlUS cEllS iN XIII–XV, 1/ 2 XI –XIII iN SOmE SPEcimENS. DORSal blOOd VESSEl ORigiNaTiNg FROm XV– XVIII. SEmiNal VESiclE WEll-dEVElOPEd, OccUPYiNg X–XI. SPERm FUNNEl laRgE, hEmiSPhERical, SlighTlY lONgER ThaN WidTh (ca. 180–200 Μm bY 110–144 Μm iN ViVO), OccUPYiNg 1/2 OF ThE caViTY iN XI. COllaR NaRROWER ThaN FUNNEl bOdY, ca. 100 Μm iN WidTh aNd 14 Μm iN hEighT iN ViVO. SPERmaTOZOa mUch lONgER ThaN SPERm FUNNEl, ca. 150–270 Μm iN ViVO. BURSal SliT H-ShaPEd. SPERmaThEca WiThOUT EcTal glaNd. EcTal dUcT VERY lONg, ca. 350 Μm lONg aNd 30 Μm WidE iN ViVO, PROJEcTiNg dEEPlY iNTO amPUlla (Fig. 4E). AmPUlla PYRiFORm, WiThOUT diVERTicUla, 150 Μm lONg aNd 75 Μm WidE iN ViVO, diVidEd iNTO TWO diSTiNcT PaRTS, EcTal aNd PROXimal. ENTal dUcT NaRROWER ThaN amPUlla, WiTh iRREgUlaR OUTliNE aNd ThiN EPiThEliUm, aNd SEPaRaTElY JOiNiNg OESOPhagUS iN VI (Fig. 4E).

Differential diagnosis. EXcEPT FOR ThE bOdY SiZE (39–56 SEgmENTS VS. 60–70 SEgmENTS iN F. peregrinabunda), OUR SPEcimENS cONFORm WEll TO ThE dEScRiPTiON OF F. peregrinabunda giVEN bY SchmElZ (2003), SUch aS 2 chaETaE PER bUNdlE aNd ThE STRUcTURE OF SPERmaThEca. ThiS iS ThE FiRST REcORd OF ThE SPEciES iN ChiNa.