Sparganophilus sp

Sparganophilus sp 10

Figures 8D–F View FIGURE 8 ; 9E–F View FIGURE 9

Material: GTIC-11507; One adult, Falling Creek , Hitchiti Experimental Forest, Jones Co., Georgia, USA. Collected from silty sediments along the creek bank, rich in organic matter, under a slope with some perennial herbs. Col. R. Carrera-Martínez, M.K. Taylor. 2. MAY.2017 (33.03521°N, 083.71082°W) GoogleMaps .

Diagnosis: Length 90 mm. Dorsal pores absent. Clitellum saddle-shaped in xv–xxvi, ventral limit in a. Tubercula pubertatis continuous in xxi–xxii, bilobate (or slightly constricted in the middle), ventral limit just dorsal to b. Setae closely paired: ab = cd, aa <bc <dd. Spermathecal pores aligned with c, in 6/7–8/9. Prostatic pores absent. Secondary annulation present on i–xv. Genital tumescences surrounding ab in xv–xvii and xxii–xxvi all weakly developed. Intestinal origin in ix. One pair of spermathecae per segment in vii–ix, spermathecal structure poorly differentiated into ampulla and duct, duct tubular, as long as the elongated, ellipsoidal ampulla. Prostate-like glands and auxiliary prostate-like glands absent. First nephridia in xiii.

Description: Length of unamputated preserved specimen 90 mm. Diameter in x 2.5 mm, in clitellum 3.5 mm. Number of segments, 249. Body ovate in cross-section anteriorly, dorsoventrally flattened at the clitellum, quadrangular posterior to the clitellum, tail quadrangular and dorsoventrally flattened, anus a dorsal slit. Preserved specimens with a pale-whitish coloration, reddish-pink anteriorly, clitellum pinkish-white. Cuticle with a strong yellowish-green iridescence. Prostomium zygolobic. Dorsal pores absent. Spermathecal pores in 6/7–8/9 level with c, minute or inconspicuous. Female pores minute in xiv, anterior to a. Male pores lateral to b in xix close to 19/20, aligned with the tubercula pubertatis. Clitellum in xv–xxvi, saddle-shaped but almost annular, ventral limit in a. Tubercula pubertatis continuous xxi–xxii, bilobate, ventral limit dorsal to b. Prostate-like pores absent. Nephridiopores anterior to b, starting in segment xiii. First setae in ii, lumbricine, closely paired. In x aa:ab:bc:cd: dd = 5.50:1.00:6.50:1.00:10.00, in xxx = 5.50:1.00:7.50:1.00:10.00; cd and most of ab not observed in clitellum. Secondary annulation present in ii–xv, throughout the whole segment, ringed with 3–4 annulations; posterior to the clitellum, secondary annulation superficial. Genital tumescences strong in xv, weak in xvi–xvii and xxii–xxvi surrounding ab. Lateral dark spots present at or above the mid-lateral line, in an irregular row in i–xiv. Dorsal pit absent.

Septa 7/8–8/9 only slightly thickened. Pharynx ends in vi, paired glands in iii–iv. Intestine originates gradually in ix. Intestinal caeca, typhlosole, calciferous glands, and gizzard absent. One pair of spermathecae per segment in vii–ix, without diverticulum. Spermathecal structure poorly differentiated into ampulla and duct, all similar size. Duct tubular, slender, as long as the ampulla. Ampulla elongated, slender, ellipsoidal, smooth, tip digitiform. Duct connects to the intersegmental furrows level with the setal line cb. Spermathecae located between a weak muscular fiber originating anteriorly in the intersegmental section of the esophagus and connecting posteriorly to the intersegmental-septum joint. Ovaries in xiii, free, string-like. Oviduct connects in segment xiv, anterior to b. Testes free in x and xi. Epididymis not observed. Seminal vesicles, free in xi, and xii, large, filling most of the celomic cavity, racemose. Vas deferens within muscular body wall. Tubular, prostate-like glands, and auxiliary prostate-like glands absent. One pair of holonephridia per segment, starting at xiii. Holonephridia of xiv reduced and smaller than xiii. Those of xiii of same size as the ones in xv–xxvii, but smaller than those in xviii and posteriorly. Bladder globular, with a “caecum” at the base of the bladder, ventrally with a U- to C-shaped vesicle. Base of the duct considerably widened, connected to 1–3 vascular stoma. Bladder connected to the lateral blood vessels. Paired moniliform hearts in vii–xi; all approximately same size. Dorsal and ventral vessel present, and simple. Paired lateral vessel present, joining dorsal vessel in xiv, filiform.

Remarks: Sparganophilus sp 10 seems closely related to S. gatesi Reynolds 1980 , and S. helenae Reynolds 1980 in having a reduction of the tubercula pubertatis (being absent in S. helenae and in xxii–xxiv in S. gatesi ). However, it differs from these species in the intestinal origin in ix (viii in S. helenae and x in S. gatesi ), size (40 mm long in S. gatesi , 140–165 mm for S. helenae ), extension of the clitellum [xv–xxiv in S. gatesi , xv–xxii, (1/n)xxiii in S. helenae ] and tubercula pubertatis. Further, Sparganophilus sp 10 seems to lack prostate-like glands, while S. gatesi and S. helenae have them in xxi–xxiv and xxiii–xxv, respectively. These species differ so much from the other known sparganophilids that they might be placed in a separate genus in the future, when new DNA sequences and adequate morphological descriptions are available for them. However, a single individual of Sparganophilus sp 10 has been collected and both S. helenae and S. gatesi seem to be rare ( Reynolds 1980, 2008).