A new species of Urocopitid land snail from Haiti and a discussion of the genus Autocoptis (Gastropoda: Urocoptidae)
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Abstract Autocoptis paulsoni n. sp. is described from Haiti. it is characterized by its large size, its cylindricaltapered shape, its fine costate sculpture on the teleoconch, a distinct but weak circum basal keel and its abbreviate conical juvenile shell. it is most similar to Autocoptis gruneri (Dunker 1844), which is redescribed, and its distribution is reviewed. The taxonomic status of the genus Autocoptis Pilsbry 1902 and its subgenus Urocoptola Clench, 1 935 are reviewed. The genus is endemic to Hispaniola and satellite islands. Key words: Gastropoda, Urocoptidae, Autocoptis, Urocoptola, land snail, Hispaniola, Haiti. Resumen Para Haití se describe Autocoptis paulsoni n. sp. Esta especie se caracteriza por su gran tamaño, su forma cilíndrica-cónica, teleoconcha en forma de costillas, una clara pero débil quilla circumbasal y concha juvenil cónica y abreviada. Es muy similar a Autocoptis gruneri (Dunker, 1844), que se describe de nuevo y su distribución se revisa. También se presenta el estado taxonómico del género Autocoptis y del subgénero Urocoptola. El género es endémico de La Española y las islas satélites. Palabras clave: Gastropoda, Urocoptidae, Autocoptis, Urocoptola, caracol terrestre, La Española, Haití.
The Urocoptidae of Hispaniola remain poorly known. Most species have received little notice in the literature since their original descriptions, except for repeated citations of previous information. Autocoptis Pilsbry (1903) is one such genus. it occurs exclusively on Hispaniola and satellite islands. Clench (1966) proposed the subgenus Urocoptola for those species of Autocoptis that do not have a crenulated suture as opposed to other species of Autocoptis, in which the suture is crenulated by the upper ends of the costate sculpture. Pilsbry (1903) monographed Autocoptis when he named the genus. Later, Pilsbry (1933), and Pilsbry (1938) described four additional species, and Pilsbry & Olsson (1954) described a Miocene species that was questionably referred to Autocoptis. Bartsch (1932) described a new species from the off-shore Beata island. Clench (1935) described three new species and two new subspecies, and established the subgenus Urocoptola. Later, Clench (1966) described three additional species of Urocoptola. Thompson & Franz (1976) described three new species of Autocoptis. Richardson 1991, without discussion, treated Urocoptola as a synonym of the Jamaican genus Urocoptis. Twenty-six species, 9 subspecies and 3 species of uncertain status currently are placed in the genus Autocoptis (Appendix 1). In 1962 Dennis R. Paulson visited Haiti for the purpose of collecting natural history specimens, including mollusks. Paulson gave the molluscan specimens to the author. Among several novelties that he found is a new species of Autocoptis. At the time I prepared a description of the new species, completion of a manuscript was postponed because of other priorities. I described the new Autocoptis to complement recent investigations of urocoptoid families from Mexico and Central America (Thompson 1968, Thompson 1976, Thompson & Correa 1991, Thompson in press). i am pleased to name the new species after its discoverer, Dennis R. Paulson. Material and methods This study is based on 31 dry specimens and two preserved specimens of the new species. Live specimens were preserved in the field in 75% ethanol. Dissections were made in 75% ethanol. Shell measurements are given in mm and are standard for elongate-cylindrical shells. The length of the shell is measured from the tip of the apical plug to the base of the peristome. The width is the width of the spire perpendicular to the shell length but does not include the peristome. The columella is viewed by filing open the shell to expose internal structure. Anatomical drawings were made with the aid of a Bausch & Lomb dissecting microscope and a camera lucida. Results Autocoptis (Urocoptola) paulsoni new species Figs. 1-6 Diagnosis: A species related to Autocoptis (Urocoptola) gruneri (Dunker 1863), because of size, its sculpture, coloration, and a circumumbilical keel on the base of the last whorl. it is distinguished from A. gruneri by its cylindrical-tapered shape, by its narrower juvenile shell, by having a lusterless white shell with more numerous fine, flat, thread-riblets, by having a weaker umbilical keel, and by the following measurements; standard length, 24.8-2; standard width, 9.2-10.3mm; aperture width, 6.8-7.8mm; 7.3-8.5 whorls retained in decollated adult shells. Shell (Figs. 1-6): Mature shells are lusterless white, are up to nearly 30mm in standard length, are moderately stout, being 0.34-0.37 times as wide as long, and are decollated with 7.3-8.5 whorls remaining below the apical plug (vestiges of earlier whorls in the holotype and paratypes were removed to expose the plug). The shape is cylindrical-tapered with the tapered portion of the upper spire consisting of 4-6 whorls which regularly increase in size. The first whorl at the point of decollation is 4.5-5.0mm wide. initially the juvenile shell is weakly concave or straight sided in outline (Fig. 5). The whorls nearly uniformly increase in size. The rate of growth of the juvenile shell indicates that 5-7, but usually 6 whorls are lost above the point of decollation at the apical plug (Fig. 4). The apical plug is elongate and laterally flattened as a tongue-like extension upward along the columella. The external color is dull-white. The base of the last whorl is tinged reddish due to the internal coloration. The peristome is white, fading into the rustcolored aperture deeper in. The septum of the first remaining whorl is pinkish. Below the first septum the interior of the whorls are white down to the penultimate whorl. internally the last whorl is tinged pink to dull red due to one band that begins along the suture, and another band that begins on the columella. The bands spread to color the columella and the last whorl internally dark rust-colored or red. The first 1.75 whorls of the protoconch are smooth, after which very fine riblets develop into distinct uniform riblets by the end of 2.5 whorls. The teleoconch whorls are slightly convex and shiny and are crossed by obsolescent, oblique, flat, thread-riblets. The penultimate whorl has 57-85 riblets. On the cylindric part of the shell the riblets increase in width on successive whorls where they are flat and close, and the interspaces are indicated only by incised grooves. The riblets become more pronounced on the periphery and base of the last whorl, and again become very fine in the umbilical chink. The suture is slightly impressed and is not crenulated by the upper ends of the riblets on the last whorl or two. The base of the last whorl has a poorly developed circum-umbilical keel (Fig. 3). The umbilicus is imperforate. The aperture is circular in shape. it is prosocline at an angle of about 22-25º to the shell axis (Fig. 2), so that in a frontal view it appears wider than high (Fig. 1). The peristome is nearly uniformly reflected along the columellar, basal and palatal margins of the aperture, and is attached to the preceding whorl across the parietal wall. The columella is solid, straight and slender, but increases in diameter in the last three whorls, and is off-set in the last whorl (Fig. 6). A low, medium-placed columellar lamella is present in the last two whorls, but it does not enter into the aperture.
Measurements of the holotype (UF 46290) and eight paratypes (UF 446290) are presented in table 1. Anatomy (Figs. 12-14): The sole is unipartite. The margin is bordered by a row of high pilaster-like folds. The dorsal surface of the foot is pebbled. The posterior-dorsal margin is rounded. The salivary glands (not figured) are about 5mm long, elongate-ovate in shape and are loosely connected above the esophagus. The salivary ducts are long and slender. Retractor muscle system (Figs. 13, 14): The columellar retractor muscle (Fig. 13) is large and stout, and attaches to the columella at about two whorls into the shell. The retractor muscle gives rise to three branches from about the same point, the dorsally located pharyngeal retractor and the two laterally placed pedal retractors. The pharyngeal retractor divides into three short branches that insert at the apex of the pharynx (Fig. 14). An elongate muscle slip originates on the dorsal surface of the pharyngeal retractor and inserts at the end of the odontophore sac. The right pedal retractor passes through the genital atrium, attaches at its midpoint to the apex of the penis and continues forward to the foot. The right ocular retractor originates on the outer margin of the right pedal retractor. The left ocular retractor originates on the outer margin of the left pedal retractor. Reproductive system (Fig. 12): The genital atrium is short, about 0.6mm long. The penis is large and club-shaped, 7.5mm long. A slip of muscular tissue connects the apex of the penis to the vagina. The penis bears a large internal fold. An epiphallus is absent. The vas deferens is simple, extending from the apex of the penis as a narrow duct, and increases in size near the prostate where it is imbedded at the base of the oviduct. The albumen gland is large, reniform in shape and is 9mm long. The ovotestis consists of three lobes; each lobe consists of about 10-20 elongate digitiform lobules. The hermaphroditic duct is about 11mm long, slender and simple near the ovotestis, and becomes thicker and convoluted midway to the albumen gland where it enters near the junction with the prostate-oviduct. The prostate-oviduct is long, simple and tapering at the lower end. The free oviduct is 7mm long, slender and tapered. The spermathecal duct lacks an appendix, is about 11mm long, slender, and enters the free oviduct shortly above the atrium to form a short vagina. Type locality: Haiti, Dept. de l’Oest, 3km Southeast of Trou Forban, (18.92º N - 72.63º W), ca. 700m alt. Holotype UF 46290; collected by Dennis R. Paulson; August 14, 1962. Paratypes: UF 446290 (20 adults), UF 446789 (10 juveniles); same data as the holotype. Distribution: Haiti; known only from the type locality. A diagnosis of Autocoptis gruneri is given for comparison with Autocoptis paulsoni.
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Autocoptis (Urocoptola) gruneri (Dunker 1844) Figs. 7-11 
