Sparganophilus borgesae Carrera-Martínez, 2025

Sparganophilus borgesae Carrera-Martínez sp. nov.

urn:lsid:zoobank.org:act:ACF38BE1-1938-4576-90C7-4A81B3E23541

Figures 7A–C View FIGURE 7

Holotype: GTIC-11490; One adult, unnamed first order tributary to Falling Creek , Scull Shoals Experimental Forest, Greene Co., Georgia, USA. Coll. R. Carrera-Martínez, & M.K. Taylor, 14.JUL.2017. (33.74306°N, 83.25230°W) GoogleMaps

Etymology: Named after Dr. Sonia Borges, pioneer of Caribbean earthworm taxonomy and who introduced the first author to the field.

Diagnosis: Length 75 mm. Dorsal pores rudimentary. Clitellum saddle-shaped in xv–xxvi, ventral limit in b. Tubercula pubertatis continuous in xvii–xxii, band-shaped, ventral limit dorsal to b. Setae closely paired: ab = cd, aa <bc <dd. Spermathecal pores in 6/7–8/9, inconspicuous. Pores of prostate-like glands in xxiii–xxiv. Secondary annulation absent. Genital tumescences surrounding ab weakly developed in xvii–xxv. Genital pad band-shaped in xxvi. Intestinal origin in ix. One pair of spermathecae per segment in vii–ix, spermathecal structure moderately differentiated into ampulla and duct, smooth, duct tubular, three times as long as the globular ampulla. Prostate-like glands in xxiii–xxiv and auxiliary prostate-like glands absent. First nephridia in xiii, tubular bladder, wide u-shaped vesicle.

Description: Length of unamputated preserved specimen 75 mm. Diameter in x 2.5 mm; in the clitellum, 3.3 mm. Number of segments, 184. Body ovoid in cross-section anteriorly, ventrally flattened at the clitellum, quadrangular in cross-section posterior to the clitellum. Preserved specimens with a pale whitish coloration, clitellum pale. Cuticle with a green and blue iridescence. Prostomium zygolobic. Dorsal pores rudimentary, discontinuous throughout. Spermathecal pores in intersegmental furrows 6/7–8/9, inconspicuous. Female pores in xiv, anterior to ab, minute but visible. Male pores lateral to b in xix, pre-setal, at the dorsal margin of tubercula pubertatis. Clitellum in xv–xxvi saddle-shaped, ventral limit in b. Tubercula pubertatis continuous xvii–xxii, band-shaped, ventral limit dorsal to setae line b. Prostate-like pores in xxiii–xxiv next to b. Nephridiopores anterior to ab, closer to a, starting in segment xiii, minute but visible. First setae in ii, lumbricine, setae closely paired. In x aa:ab:bc:cd:dd = 6.50:1.00:7.50:1.00:10.00, in xxx = 6.50:1.00:8.00:1.00:10.00. Secondary annulation absent. Genital tumescences surrounding ab in xvii–xxv, weakly developed. Genital pad band-shaped in xxvi extending to setal line b. Post-setal dark spots visible just ventral to c, in a regular line in i–xiv. One dorsal depression in the equator of peristomium.

Septa 6/7–8/9 only slightly thickened. Pharynx ends in segment iv, joining a small esophagus. Intestine originates abruptly in ix. Intestinal caeca, typhlosole, calciferous glands, and gizzard absent. One pair of spermathecae in vii–ix, without diverticulum. Spermathecal structure moderately differentiated into ampulla and duct, all similar size. Duct about half the length of the ampulla, tubular, wide. Ampulla elongated, globular, rugose laterally, tip digitiform. Spermathecae located between a weak muscular fiber originated 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 a. Testes free in x and xi. Epididymis small. Seminal vesicles, free in xi, and xii, large and restricted to their segment. Vas deferens within muscular body wall. Tubular, prostate-like glands in xxiii–xxiv, long, slender, and coiled. Auxiliary prostate-like glands absent. One pair of holonephridia per segment, starting at xiii. Holonephridia tubular, bladder composed of highly coiled tubules dorsally, ventrally with a wide u-shaped vesicle, all same size. Holonephridia of xiv attached to 13/14 septa, without vesicle. Paired moniliform hearts in vii–xi; vii smaller than the rest. Dorsal and ventral vessel complete, and simple. Paired lateral vessel present, joining dorsal vessel in xiv, filiform.

Remarks: Sparganophilus borgesae sp. nov. differs from all other known Sparganophilus by having only two pairs of well-developed prostates in xxiii–xxiv, rudimentary dorsal pores, presence of a genital pad, and a dorsal pigmented pit on the equator of the prostomium. We decided to describe and name this species, despite having only a single specimen after a year of collection at this site. Furthermore, previous sampling efforts by Ikeda et al. (2020) in and around this area did not yield any match to this species, suggesting that S. borgesae might be a rare species. Given that no additional specimens were found, that 28S, 16S, and COI genetic distance are large and having distinct morphological differences, we followed Fragoso & Rojas (2019) recommendations on describing singleton earthworm species.