Three new Neotropical species and a new genus of land flatworms (Platyhelminthes, Geoplaninae)

Three new Neotropical land planarians (Platyhelminthes, Tricladida, Geoplaninae) from the Brazilian Atlantic forest are described. Obama apiguara Oliveira, Almeida & Carbayo sp. nov. presents glandular fossae opening through dorsal epithelium, a structure not documented previously among land flatworms. Paraba tata Bolonhezi, Lago-Barcia & Carbayo sp. nov., is characterized by a prostatic vesicle horizontal with an inconspicuous bifurcate portion, a penis papilla as long as male atrium and a female genital duct projected from the postero-dorsal section of the female atrium. The third new species is distinctive in the extraordinarily thick muscle surrounding the prostatic vesicle, a finger-shaped penis papilla, and a dilated female genital cavity. These attributes stands the species apart from all members of Geoplaninae and Piima ata Carbayo gen. et sp. nov. is proposed.


Introduction
Land planarians (Platyhelminthes Gegenbaur, 1859, Tricladida Lang, 1884, Geoplanidae Stimpson, 1857 are richly diversifi ed in the Brazilian Atlantic forest (Sluys 1999). Most species in this biome belong to the exclusively Neotropical subfamily Geoplaninae Stimpson, 1857, with 25 genera plus the collective genus Pseudogeoplana Ogren & Kawakatsu, 1990. This genus houses species of Geoplaninae, whose internal morphology remains unknown, particularly that of the copulatory apparatus. This organ is the main morphological character used in planarian taxonomy. Currently, the subfamily encompasses 332 species (Carbayo 2019).
Over the last ten years, we have been conducting intense sampling for these organisms across the south and southeast portions of the Atlantic forest from the state of Espírito Santo to Rio Grande do Sul. As part of the samplings, we collected representatives of three unknown species. One of the species is a member of Obama Carbayo et al., 2013, another species belong to Paraba Carbayo et al., 2013 and the third species is placed in a new genus herein proposed.

Material and methods
Specimens were found through a visual search on the soil litter in the forest during the day and night. We took pictures of them, and killed them in boiling water. We fi xed the remaining part of the body in 10% formalin or 80% ethanol and, subsequently, transferred it to 80% ethanol. The body was cut into portions which were embedded in Histosec® paraffi n, sectioned at 4-7 μm, and subsequently stained on glass slides with the Mallory method as modifi ed by Cason (1950). We examined the sections and reconstructed the copulatory apparatuses and pharynges with a compound microscope and a camera lucida attached. We took digital photomicrographs with the help of a digital camera Olympus DP72 attached to the microscope. We enhanced the contrast of the photomicrographs and provided a whitish background with GIMP (GNU Image Manipulation Program vers. 2.8.16; the GIMP Team www. gimp.org, 1995-2016). We orientated the drawings and the photomicrographs of sagittal and horizontal views with the anterior body region to the left.
Specimens examined in this study were deposited in MZUSP = Museu de Zoologia da Universidade de São Paulo.
Abbreviations in the fi gures c = circular cutaneous muscle cg = cyanophil gland cells co = common glandular ovovitelline duct dc = diagonal decussate cutaneous muscle de = dorsal epidermis di = dorsal insertion e = eye ej = ejaculatory duct es = esophagus fa = female atrium fc = female genital cavity fd = female genital duct g = gonopore gf = glandular fossa gl = glands gm = glandular margin i = intestine de OLIVEIRA K.G. et al., A new genus and three new species of fl atworm from Brazil lc = longitudinal cutaneous muscle lu = pharyngeal lumen m = muscle ma = male genital atrium mc = muscular coat mo = mouth ms = thin muscle fi ber o = ovary ov = ovovitelline duct ph = pharyngeal pouch pi = intra-papillar papilla pp = penis papilla pv = prostatic vesicle px = pharynx r = recess of male atrium sb = subintestinal transverse muscle sd = sperm duct sn = sensory pit sg = shell glands sp = supraintestinal transverse muscle t = testis v = vitellaria ve = ventral epidermis vi = ventral insertion vn = ventral nerve plate

Diagnosis
A species of Obama with a dark ivory dorsum, dark tips and numerous small longitudinal black striae and a glandular fossae opening through the epidermic epithelium. The subintestinal parenchymal muscle is intermingled with the nerve plexus. The penis papilla is provided with a small intra-papillar, fi ngerlike papilla. A common glandular ovovitelline duct is absent. The female genital duct projects from the mid-dorsal section of the female atrium.

Description
MEASUREMENTS. The holotype, preserved, is 56 mm long and 8 mm wide.
BODY. Broad and fl attened dorsoventrally. The body margins are nearly parallel, except the anterior 25%, and the posterior 17% of the body, which are pointed and obtuse, respectively. The dorsum is slightly convex, the ventral side fl at. The color of the dorsum of the living specimen is dark ivory, pigmented and with numerous small longitudinal black striae formed by small spots. The anterior and posterior extremities, each 10-15% of body length, exhibit a black pigment. This pigment almost covers the striae (Fig. 1A). The ventral side is pastel-yellow in color, whitish in the region of the pharynx and the copulatory apparatus, and brown in both extremities (17% of the length of the body) (Fig. 1B).
EYES. Single-lobed and without halos, measuring about 50 μm in diameter. They are absent at the very anterior apex of the body ( Fig. 2A) and are initially uniserial. Behind 4 mm (7% of body length from anterior tip), they are arranged in 2-3 marginal rows, which reach, on each side, approximately 0.7 mm of the total body width (1.25% of the body width). The eye distribution reaches the region of the gonopore, behind it becoming scarcer until the posterior tip of the body. The sensory pits are about 45 μm deep, and are distributed in a single ventro-marginal row. They contour the anterior extremity of the body and are distributed along the body until 14 mm from anterior extremity (25% of body length). CREEPING SOLE. Occupies approximately 96% of the body width. The positions of the mouth and the gonopore relative to the anterior tip are about 70% and 85% of the body length, respectively. In the prepharyngeal region (Fig. 2B), the dorsal epithelium is crossed by necks of rabditogen cells, especially on the sides of the body; it is also crossed by necks of cells producing fi ne (1.2 μm) cyanophil granules and by necks of scarce cells producing xanthophil and erythrophil granules, respectively. The ventral epithelium is traversed by an abundant number of necks of cells producing cyanophil granules and a low number of necks of cells producing either xanthophil or erythrophil fi ne granules. In the body margins, the density of gland cells slightly increases giving rise to a poorly delimited glandular margin (Fig. 2B). ANTERIOR 45% OF THE BODY. Presents a structures herein called glandular fossae. These glandular fossae are distributed irregularly in a simple or double row along the dorsal and body margins (Fig. 3). A few fossae are also found in the ventral body margins (Fig. 3E). A glandular fossa consists of a 30-70 μm deep invagination, mostly simple (Fig. 3C), sometimes bifurcate (Fig. 3D). The invaginations are lined with a 5-15 μm high epithelium, that is lower than surrounding body epithelium (25 μm high). Cells of the lining epithelium are strongly erythrophil. The lumen of the fossae seem to contain red-pinkish threads and fi ne erythrophil granules. Necks of glands producing xanthophil secretions are located in surrounding parenchyma of the fossae, but they apparently do not discharge their secretion into the fossae but through surrounding epidermal cells.  CUTANEOUS MUSCULATURE. Organized in three layers: a subepithelial layer of circular fi bers, followed by a layer of double diagonal fi bers and a longitudinal one with bundles composed of 32-96 fi bers each. The thickness of the cutaneous musculature is 10% of the body height in the pre-pharyngeal region. The parenchymal musculature is composed of a dorsal layer of diagonal fi bers, followed by a supraintestinal layer of transverse fi bers and a subintestinal layer of transverse fi bers extending below the nerve plate, thus intermingled with it. The main nervous system presents the shape of a plate (Fig. 2C).
MOUTH. Opens at the end of the second third of the pharyngeal pouch. The pharynx is cylindrical (Fig. 4A), with the dorsal insertion posteriorly shifted. It occupies 77% of the length of the pharyngeal pouch. An esophagus is present; under its lining epithelium, there is a one-fi ber-thick muscle layer followed by a layer (50 μm) of circular fi bers interspersed with longitudinal fi bers. The pharynx is lined with a cuboidal, ciliated epithelium. The pharyngeal epithelium is crossed by necks of three types of gland cells producing erythrophil, cyanophil and xanthophil granules, respectively. The outer pharyngeal epithelium is lined with a longitudinal muscle (5 μm), followed by a circular muscle (5 μm). The inner pharyngeal epithelium is lined with a a layer (100 μm) of circular fi bers interspersed with longitudinal fi bers, followed by a one-fi ber-thick layer of longitudinal fi bers.
TESTES. Dorsal, with a round shape, the largest being about 300 μm in diameter. They are arranged in 3-4 rows on each side of the body, starting 13 mm behind the anterior extremity of the body and reaching 20.5 mm, which corresponds to 23% and 37% of the body length, respectively.  EFFERENT DUCTS. Bend upwards and forwards before ending in the proximal portion of the prostatic vesicle. The prostatic vesicle is extrabulbar, elongate and exhibits an inverted-U shape in lateral view. The proximal portion of this vesicle is forked. The vesicle enters the ventro-anterior section of the penis bulb to communicate with the ejaculatory duct. The prostatic vesicle is lined with a columnar, ciliated epithelium which is crossed by necks of cells producing erythrophil granules. This epithelium is surrounded by a circular muscle (160 μm thick), the ectal fi bers of which are decussate.
EJACULATORY DUCT. Meanders in the fi rst half of its length and becomes straight in the second half. This duct crosses the center of the intrapenial papilla, and its lining epithelium is columnar (25 μm tall) and ciliated. This epithelium is crossed by necks of cells producing erythrophil granules in its fi rst half; in its second half, it is pierced by necks of cells producing cyanophil granules. The epithelium is surrounded by a circular muscle (30 μm thick). PENIS PAPILLA. Larger than the male atrium and cylindrical, with its dorsal insertion slightly anterior to its ventral. It is provided with a fi nger-like intra-penial papilla with 600 μm in length, which is oriented postero-dorsally (Figs 4B,5). The epithelium of the intra-penial papilla is 5 μm high, and crossed by necks of cells producing erythrophil and cyanophil granules, respectively. This epithelium is underlain by a 2 μm thick longitudinal muscle, followed by a circular muscle (6 μm thick). This intra-penial papilla has radial muscle fi bers and is provided with a sort of penis bulb constituted by crossed fi bers. The large penis papilla is lined with a cuboidal-to-columnar epithelium, which is pierced by necks of abundant cells producing erythrophil granules. This epithelium is underlain by a circular muscle (15 μm thick), followed by a longitudinal muscle (20-30 μm thick), both layers being intermixed close to the insertions of the penis papilla. MALE ATRIUM. Large and not folded, lined with a squamous-to-cuboidal epithelium, which is crossed by necks of cells producing erythrophil granules and a low number of necks of cells producing xanthophil granules. This epithelium is underlain by a circular muscle (17.5 μm thick), which in some areas presents intermingled longitudinal fi bers. OVARIES (Fig. 2C). Ovoid, 550 μm in length and 300 μm in width, approximately. They are situated at a distance from the anterior extremity of the body, equivalent to 27% of the body length. The ovovitelline ducts emerge from the dorso-lateral region of the ovaries and subsequently run above the nerve plate, ventrally to the efferent ducts. At the level of the gonopore, the ovovitelline ducts bend dorsally to join the female genital duct, which is a projection of the dorso-medial wall of this atrium (Fig. 5). There is no common glandular ovovitelline duct. The distal portion of the ovovitelline ducts receives secretions from the shell glands. The female genital duct is lined with a 75 μm high, non ciliated epithelium. This epithelium is crossed by necks of two types of cells producing erythrophil and cyanophil granules, respectively. FEMALE ATRIUM. Large and as long as the male atrium. The anterior portion of the atrium does not narrow and continues with the male atrium (Figs 4B, 5). The female atrium exhibits 2-3 lateral folds that partially occupy its lumen. It is lined with a non-ciliated epithelium, with a stratifi ed appearance in its posterior region. Towards the anterior portion of the atrium, this epithelium passes progressively to cuboidal (30 μm high, ventrally) or columnar (75 μm high, dorsally), and is crossed by necks of cells producing erythrophil granules and by a low number of necks of cells producing coarse cyanophil granules. The posteriormost section of the female atrium is pierced by cells producing a xanthophil amorphous secretion. The epithelium of the atrium is underlain by a longitudinal muscle (8 μm thick), followed by a circular muscle; fi bers of both muscles are intermingled in some parts.

Remarks
This new species best matches Obama, since it presents the diagnostic features of this genus, with the exception of the eyes, which are only monolobate, the small intra-papillar fi nger-like penis papilla, and the female genital duct projecting from the dorsal side of the female atrium.
Among the 39 members of Obama, only four species also display a similar dorsal color pattern consisting of longitudinal dark small dots on a light ground color, namely O. allandra Marques et al., 2018, O. nungara Carbayo et al., 2015, O. maculipunctata Rossi et al., 2015and O. marmorata (Schultze & Müller, 1857. Among them the striae in O. marmorata and O. nungara only form irregular longitudinal stripes as in the new species. However, in O. nungara, the irregular stripes are wider and the ground color is darker. Obama marmorata is very similar to the new species. Differences are related to the stripes, which are more evident in O. marmorata, and to the darker anterior and posterior body tips, restricted to a short body portion in O. marmorata. Among the species of Pseudogeoplana, only Ps. blanchardi (Graff, 1899) and Ps. doederleine (Shirch, 1929) somewhat resemble our species in the marbled aspect of the dorsum. However, in Ps. blanchardi, from Venezuela, the dark spots are rounded (vs striated in O. apiguara sp. nov.); in Ps. doederleine, from Rio Doce (Rio de Janeiro), the spots are absent in a midband which is ornamented with four brownish thin longitudinal stripes (vs absent in Obama apiguara sp. nov.).
Regarding internal morphology, the copulatory apparatus of Obama apiguara sp. nov. resembles that of O. applanata (Graff, 1899) and O. carrierei (sensu Marcus, 1951) in that the latter species present a structure similar to an intra-penial papilla as in the new species (see Marcus 1951: fi g. 169;Froehlich 1956: fi g. 2). However, O. applanata and O. carreirei differ from the new species in the following aspects: they a) present the dorsal insertion of the penis papilla shifted posteriorly (vs anteriorly in the new species); b) possess a common glandular ovovitelline duct (vs absent in Obama apiguara sp. nov.); and c) their female genital duct projects from the posterior (O. carreirei) or postero-dorsal aspect (O. applanata) of the female atrium (vs dorsal). In addition, to the best of our knowledge, the new species is the only land planarian having glandular fossae opening through epidermis.

Distribution
Only known from the type locality.

Diagnosis
A species of Paraba, with a dark orange-brown dorsum, a median narrow clear grey stripe and orange body margins; the prostatic vesicle horizontal with an inconspicuous bifurcate portion; the copulatory apparatus relatively long; the penis papilla as long as the male atrium; the female genital duct projected from the postero-dorsal section of the female atrium.

Etymology
The name 'tata' (tatá) is a Tupi (indigenous Brazilian language) word meaning 'fi re' (Tibiriçá 1984). It refers to the color of the dorsum.
Paratypes BRAZIL • 1 adult; same collection data as for holotype; transverse sections of cephalic region on 16 slides, horizontal sections of portion behind cephalic region on 9 slides, sagittal sections of pharynx and copulatory apparatus on 16 slides; fi eld number F3151; MZUSP PL2185 • 1 adult; same collection data as for preceding; transverse sections of cephalic region on 18 slides, horizontal sections of portion behind cephalic region on 8 slides, sagittal sections of pharynx on 22 slides, sagittal sections of copulatory apparatus on 15 slides; fi eld number F3768; MZUSP PL2186.

Description
MEASUREMENTS. The preserved paratype F3768 is 22.5 mm long and 4 mm wide.
BODY. Margins are parallel; the anterior extremity is pointed; the posterior, rounded (Fig. 6A). The dorsum is slightly convex; the ventral side fl attened (Fig. 6B). The dorsum is dark orange-brown; the body margins are orange. A narrow clear grey stripe extends along the entire body length, except for the very anterior and posterior body tips. The ventral side is ivory in color.
EYES. Monolobate and 45 μm in diameter. They contour the anterior extremity of the body (Fig. 6C) and are located dorsomarginally along the whole body, except for the very posterior extremity, where they are absent. The sensory pits are 37.5 μm deep (F3151) and are arranged in a single row that contours the anterior extremity of the body (Fig. 6D) and behind, they extend backwards to at least a length equal to 18% of the body length. The relative distance mouth to body length is 74% and the relative distance of the gonopore is 84% of the body length.
CUTANEOUS MUSCULATURE. Composed of three layers: a very thin subepithelial circular muscle, followed by a thin diagonal with decussate bundles (both layers with a height of 7.5 μm ventraly, dorsally 12.5 μm) and a thick longitudinal muscle (dorsally 87.5 μm thick, ventrally 37.5 μm) of fi bers arranged in compact bundles (Fig. 6D). The cutaneous musculature thickness relative to body height is 18%. Three parenchymal muscle layers are present: a dorsal layer (18 μm thick) with decussate diagonal fi bers, a supra-intestinal layer (50 μm thick) with transverse fi bers and a sub-intestinal layer (62 μm thick) with transverse fi bers.
MOUTH. Relative position mouth pharyngeal pouch length is 64%. The pharynx is cylindrical, with its dorsal insertion shifted backwards. A very short esophagus is present, 4% of the pharynx length (Fig. 7A).  The outer pharyngeal epithelium is underlain by a longitudinal muscle (3 μm thick), and followed by a circular muscle (5 μm thick). The inner pharyngeal epithelium is underlain by a subepithelial circular muscle (3 μm thick) followed by a longitudinal muscle (50 μm thick) with some fi bers interspersed with the circular one (paratype F3151). DORSAL TESTES. Located between the supraintestinal parenchymal muscle layer and the intestine. These testes extend from 1 mm behind the ovaries (28% of body length) to shortly before the root of the pharynx. The sperm ducts run ventrally and curve medially to communicate with the respective lateral short branches of the extrabulbar prostatic vesicle (Figs 7B, 8). The prostatic vesicle is 320 μm long, pear-shaped and horizontal; it is attached to the pharyngeal pouch. This vesicle is lined with a columnar, ciliated epithelium, which is pierced by necks of glands producing fi ne erythrophilic granules. The epithelium is surrounded by a tightly packed muscle (150 μm thick) of fi bers variously oriented. The ejaculatory duct is straight and runs through the penis papilla to open at its tip. This duct is lined with a cuboidal, ciliated epithelium, and is underlain by a circular muscle (7 μm). Cylindrical, somewhat irregular, with conical tip and dorsal insertion slightly anterior to the ventral one. It projects horizontally from the anterior wall of the male atrium (Figs 7B, 9A) and its posterior portion is slightly directed to the dorsal side. The penis papilla is lined with a cuboidal epithelium 11 μm high. The subepithelial musculature of the penis papilla consists of a 7 μm thick circular layer, followed by a longitudinal muscle 7 μm thick. The epithelium of the penis papilla is pierced by necks of glands producing erythrophil granules. These glands are absent in the tip of the papilla; instead, necks of glands producing cyanophil granules pierce the epithelium of the tip. Additionally, necks of glands producing a dark reddish secretion pierce the entire papillar epithelium. MALE ATRIUM. Exhibits a few dorsal folds. It is lined by a cuboidal, non-ciliated epithelium, which is underlain by a 7.5 μm thick circular muscle, followed in its distal half by a 5 μm thick longitudinal muscle. The dorso-anterior section of the male atrium receives necks of abundant glands producing fi ne cyanophil granules.
OVARIES. Ovoid, with a maximum diameter of 300 μm (Fig. 9B). They are located between the subintestinal parenchymal muscle layer and the nerve plate, and lie at a distance from the anterior tip of the body equal to 23% of the body length (F3768). The ovovitelline ducts arise from the mid-dorsal region of the ovaries. Before the level of the gonopore, these ducts ascend to join dorsally to the anterior section of the female atrium, subsequently forming a 500 μm long common glandular ovovitelline duct (paratype F2637) located above the female atrium (Fig. 8). The very distal ascending portion of the ovovitelline ducts receives shell glands (Fig. 8B). The long common glandular ovovitelline duct runs fi rst postero-dorsally and subsequently ventrally to communicate with the female genital duct. This duct is a projection of the dorso-posterior wall of the female atrium. FEMALE ATRIUM. Ovoid, with its anterior region narrowed (Fig. 8B). This atrium is occupied by an epithelium with a multilayered aspect with the exception of a narrow central passage. Two types of glands, producing cyanophil and erythrophil, respectively, discharge their contents into the female atrium. The female : male atrial length is approximately 2:1. The female atrium is underlain by a 75 μm thick circular muscle.

Remarks
The new species fi ts the genus Paraba Carbayo et al., 2013, since it presents all of the diagnostic characters of the genus, except for some folds of the male atrium, which are present in the dorsal section of this species. However, other species of the genus also bear some folds in the male atrium, such as P. phocaica (Marcus, 1951), P. preta (Riester, 1938 and P. tingauna (Kishimoto & Carbayo, 2012) (see Almeida et al. 2012). Folds may appear as a consequence of a contraction of the body at the time of fi xation (Negrete et al. 2015). This might be the case, since the penis papilla of the species is also bent.
In its external aspect, Paraba tata sp. nov. resembles P. goettei (Schirch, 1929), P. franciscana (Leal-Zanchet & Carbayo, 2001) and P. incognita (Riester, 1938) in having a dark dorsum with a thin light midline. However, they differ in the details: the dorsum of P. goettei is a light brown color with pinkreddish body margins and a pink-reddish median line (vs dorsum dark orange-brown, orange body margins and a grey midstripe in the new species). Furthermore, P. goettei is 100 mm long (vs 22.5 mm in the new species) and its eyes are organised in two or more rows in the anterior portion of the body (vs one row in the new species). In turn, P. franciscana differs from P. tata sp. nov. in the dark gray color of the dorsum with a white median longitudinal stripe. Finally, P. incognita is different in the clear blue dorsal midline bordered by grayish blue paramedian stripes.
A similar general color pattern, dark dorsum with a thin light midline, can be found in two species of Pseudogeoplana, namely Ps. bonita (Schirch, 1929) and Ps. ehlersi (Graff, 1899). Nonetheless, they differ in the details as follows: the thin median line of Ps. bonita is yellowish with bottle green body margins (vs clear gray median stripe and orange body margins in the new species). Furthermore, the body margins of Ps. ehlersi do not differ from the dark general color of the dorsum and are not orange as in P. tata sp. nov.
In relation with the internal anatomy, eight species of the genus share with the new species the horizontal orientation of the prostatic vesicle and the female genital duct projected from the posterodorsal section of the female atrium, namely P. caapora (Froehlich, 1957), P. franciscana, P. gaucha (Froehlich, 1959), P. incognita, P. multicolor (Graff, 1899), P. rubidolineata (Baptista & Leal-Zanchet, 2005), P. suva (Froehlich, 1959) and P. tingauna. Notwithstanding this, they differ in the details: in P. gaucha, P. rubidolineata, P. suva and P. tingauna the penis papilla is shorter than the male atrium (vs as long as the male atrium in the new species); in P. caapora, P. gaucha and P. multicolor the prostatic vesicle displays a conspicuous bifurcate portion (vs inconspicuous); in P. incognita and P. multicolor the copulatory apparatus is compact (vs relatively long); and in P. franciscana the posterior section of the female atrium is bent dorso-anteriorly (vs not bent).

Diagnosis
A Geoplaninae with a small to medium-sized body, sub-cylindrical, slender with nearly parallel margins, anterior and posterior extremities rounded. Eyes and sensory pits surround the entire cephalic region. The eyes are monolobate and distributed along the body margins. The prostatic vesicle is extrabulbar and strongly muscularized. The penis papilla is cylindrical and horizontal. The distal half of the male atrium has large folds. The common glandular ovovitelline duct is dorsal to female atrium. A female genital cavity communicates between the common glandular ovovitelline duct with and the female atrium. The female atrium is long and well muscularized.

Etymology
The name 'Piima' is a composition of the Tupi (Indigenous Brazilian language) words 'pii' (meaning 'thin', 'slender') and 'ma' ('animal') (Tibiriçá 1984). It alludes to the body shape of the type species of the genus. The gender is female.

Diagnosis
A species of Piima gen. nov. with a black dorsum having a median white band and large white dots occasionally merged with each other; the copulatory is apparatus comparatively long; the muscularis of prostatic vesicle is extraordinarily strong; the penis papilla is fi nger-shaped; the male atrium has a distal, large traversed annular fold; the female genital duct is dilated and dorso-anteriorly fl exed above the female atrium; the muscularis of the female atrium is very thick and dense.

Etymology
The name 'ata' ('atã') is a Tupi (indigenous Brazilian language) word meaning 'strong' (Tibiriçá 1984). It refers to the very thick muscle of the prostatic vesicle.

Description
MEASUREMENTS. Living holotype is 30 mm in length and 3 mm in width.
BODY. Slender, with parallel margins; the anterior is extremity rounded; the posterior extremity is pointed. The dorsal side is convex; the ventral one is fl at; the body margins are rounded. The dorsal color is black and white (Fig. 10A). The anterior 10% of the body exhibits a median black band separated from the black margins by a whitish area. Subsequently to this section, a pair of transverse black lines separated by a whitish band appears. From behind these black lines to the posterior end, the color is black except for a median white band (20% of the body width) and large white dots occasionally merged with each other. The ventral side is white, slightly gray in the fi rst two millimeters of the body.
EYES. 30-50 μm in diameter, monolobated and lacking halos. These eyes are marginally located in a single row encircling the anterior region, and distributed in two-to-three irregular marginal rows until the posterior end of the body where they are scarce. The sensory pits are simple invaginations 30 μm deep; and located ventro-marginally in a single row, from the very anterior end up to a portion equal to 30% of the body length. The relative mouth : body length is 61%; the relative gonopore : body length is 77%.
EPITHELIUM. Ciliated only in the creeping sole, which is 74% of the body width in the pre-pharyngeal region. The ventral epithelium of the cephalic region is pierced by necks of numerous cells producing erythrophil granules. Besides rhabditogen cells, the dorsal and ventro-marginal epithelium of the prepharyngeal region is pierced by necks of two types of cells producing xanthophil and cyanophil granules, respectively, the latter also discharging their content through the ventral epithelium. A glandular margin is absent.
CUTANEOUS MUSCULATURE. Consists of three muscle layers, namely a thin subepithelial layer (2.5 μm thick, dorsally and ventrally) of circular fi bers, followed by a layer of decussate fi bers (2.5 μm thick, dorsally and ventrally), and an innermost layer of longitudinal fi bers (10 μm dorsally, 18 μm ventrally), arranged in loose bundles of 4-12 fi bers each. The cutaneous musculature thickness relative to the body height is 7.4%. There are three parenchymal muscle layers: a dorsal layer (3 μm thick) of decussate fi bers, a supraintestinal layer (30 μm thick) of transverse fi bers, and a subintestinal layer (25 μm thick) of transverse fi bers, lying above the ventral nerve plate. Towards the anterior end of the body, these layers become thinner and extinct.
MOUTH. Lies about half way along the pocket (Fig. 10B). The pharynx is cylindrical, with its dorsal insertion slightly posteriorly located. An esophagus is inconspicuous. The outer pharyngeal epithelium is underlain by a one-fi ber-thick longitudinal layer, followed by a two-fi ber-thick circular one. The inner pharyngeal epithelium consists of a layer (50 μm thick) of circular fi bers with some interspersed longitudinal fi bers in its ectal portion. ROUNDED TESTES. 200 μm in diameter, located between the supraintestinal parenchymal muscle layer and the intestinal diverticula (Fig. 10C). They are arranged in a single row on each side of the body, and extend from shortly behind the level of the ovaries (equal to 21% of the body length) to closely to the root of the pharynx (equal to 56% of the body length). The efferent ducts are located between the fi bers of the transverse subintestinal muscle layer. The distal portion of these ducts contains sperm and is dilated. Reaching the penis bulb, these ducts bend anteriorly to the sagittal plane and subsequently penetrate the antero-dorsal portion of the muscularis of the prostatic vesicle to open laterally into the anterior portion of the prostatic vesicle. The prostatic vesicle is elongate, narrower distally (Figs 10D,. This vesicle is straight and inclined postero-ventrally. The lining epithelium of the vesicle is cuboidal and ciliated. Cells producing fi ne erythrophil granules and scarce cells secreting cyanophil granules discharge their products through the epithelium into the vesicle. The muscularis of the prostatic vesicle is composed of an extremely dense and thick muscle (350 μm thick) of superposed layers of diagonal fi bers. The vesicle communicates with the ejaculatory duct in the ventro-anterior section of the penis bulb. The proximal portion of the ejaculatory duct meanders towards the dorsal side; subsequently, it crosses the center of the penis papilla (Figs 10E, 11B). The ejaculatory duct is lined with a cuboidal, ciliated epithelium, and is underlain by a circular muscle, 20 μm thick anteriorly, 5 μm thick distally. PENIS PAPILLA. Close to its opening at the subapical tip, the ejaculatory duct widens slightly and the free surface of its lining epithelium is undulated and apparently not ciliated. The penis papilla is fi nger-shaped, with a conical tip, and horizontally positioned (Figs 10E,. This papilla projects from the anteroventral section of the male atrium and is half as long as the male atrium. The penis papilla is lined with a squamous-to-cuboidal epithelium, which is pierced by necks of cells producing cyanophil granules. The epithelium of the distal half of the papilla is additionally crossed by necks of cells producing xanthophil granules. The muscularis of the penis papilla is composed of a subepithelial circular muscle followed by a longitudinal muscle. These layers are dense and thick (25 μm and 15 μm each) in the proximal section of the papilla, but inconspicuous distally. MALE ATRIUM. Elongate and divided into two halves. The anterior half houses the penis papilla and is relatively smooth (Fig. 11A-B). Dorsal to the penis papilla, the male atrium possesses a recess ( Fig. 11B-C). The distal half is narrower and provided with a large, transverse annular fold. The lining epithelium of the male atrium is squamous-to-cuboidal, and is crossed by necks of cells producing granules with a weak affi nity for a cyanophil stain. In its bottom, the dorsal recess receives xanthophil granules produced by numerous cells; in its distal section, the recess receives eryhtrophil granules (Fig. 11C). The muscularis of the male atrium is strong, and composed of a dense subepithelial circular muscle, followed by a longitudinal one; the thickness of these muscles becomes highest in the midregion, 100 μm and 10 μm, respectively. A muscle coat of decussate fi bers envelopes the male atrium.
OVARIES. The vitellaria are well developed. The ovaries, ovoid, are 200 μm in length and 150 μm in diameter. They are ventrally located between the intestine and the subintestinal parenchymal muscle layer (Fig. 11D). They are located at a distance from the anterior extremity of the body equal to 20% of the body length. The ovovitelline ducts arise from the dorso-lateral aspect of the ovaries. The proximal portion of these ducts is slightly dilated and contains spermatozoa. These ducts run ventrally to the sperm ducts, between the fi bers of the subintestinal parenchymal muscle layer. Reaching the region of the gonopore, they bend obliquely to the sagittal plane and subsequently join to communicate with the common glandular ovovitelline duct, the latter located dorsally to the female atrium (Fig. 11B, E). The ovovitelline ducts are surrounded by a decussate muscle. The distal portion of these ducts receives shell glands. The common ovovitelline duct is long, horizontally placed, and surrounded by a decussate muscle 8-15 μm thick. The common ovovitelline duct connects with a short canal similar to this common duct but devoid of shell glands. In turn, this short canal opens into the anterior face of a dorsal, large and dilated female genital cavity. This cavity is located dorsally to the posterior region of the female atrium. The cavity contains a lump of a cyanophil granular mass attached to a strongly erythrophil secretion. The erythrophil secretion exhibits an amorphous aspect in some regions, while in others it is constituted of parallel strands (Fig. 11E). The female genital cavity is lined with an epithelium having a multilayered aspect and an irregular free surface; the epithelial portion nearest to the common ovovitelline duct exhibits gaps. The epithelial female genital cavity is crossed by necks of cells producing erythrophil granules, and its muscularis is composed of a circular muscle (9 μm thick), followed by a thin longitudinal muscle. The female atrium is long and spacious; it is more dilated in its midregion. It is 75% as long as the male atrium. FEMALE ATRIUM. Lined with a cuboidal, ciliated epithelium; cilia are absent near the gonopore canal. The female atrial epithelium convergent with the female genital cavity is crossed by a conspicuous mass of necks of cells producing cyanophil secretion (Fig. 11E); the rest of the female atrial epithelium is pierced by necks of cells producing cyanophil granules, and by a second type of cells producing granules with a poor affi nity for erythrophil stain. The epithelium of the female atrium is surrounded by a longitudinal muscle (9 μm thick), followed by a circular muscle (30-50 μm thick), the latter with some interspersed longitudinal fi bers, and an ectal, thin longitudinal muscle. The circular layer surrounding the middorsal and posterior portion of the female atrium is very thick and dense, reaching up to 200 μm (Fig. 11E). A muscle coat enveloping the female atrium is absent. The gonopore canal is lined by a columnar ciliated epithelium.

Remarks
This species is peculiar among the members of Geoplaninae and does not fi t well any of the 24 current geoplanin genera (the collective genus Pseudogeoplana Ogren & Kawakatsu, 1990 excluded). The species resembles more closely the diagnostic features of Paraba (Geoplaninae), in that the body is slender, the eyes are monolobate, the pharynx is cylindrical, the prostatic vesicle is extrabulbar, the penis papilla is protrusible, the ovovitelline ducts join each other above the female atrium, and the female atrium is clothed with an epithelium with a multilayered aspect (Carbayo et al. 2013). However, the copulatory apparatus is comparatively longer, the muscle of the prostatic vesicle is extraordinarily thick (vs thin), the male atrium presents a distal, large annular fold (vs not folded), the penis papilla is fi nger-shaped (vs conical) and in that there is no female genital duct but a dilated genital cavity projected forwards over the female atrium. This combination of features is unique among all members of Geoplaninae and leads to the proposal of a new genus for it. In favor of this proposal are the ambiguous phylogenetic affi nities of the species to other Geoplaninae species, as inferred from molecular data (see Carbayo et al. 2013). None of the molecular analyses placed the new species within, or sister to, the clade constituted by the type species of Paraba (i.e., P. multicolor (Graff, 1899)) and other members of this genus. The Bayesian Inference (BI) (Carbayo et al. 2013, fi g. S2B) analysis positioned the new species as a sister species of P. phocaica with a high posterior probability, whereas the Maximum Likelihood (ML) (Carbayo et al. 2013, fi g. 3) analysis shows a low support for this clade. The Maximum Parsimony (MP) analysis revealed this species as sister to a large group including members of several genera, none of them members of Paraba. Therefore, the molecular approach indicates that Piima ata sp. nov. does not show a close relationship to any of the genera, nor do the morphological attributes support the membership of these species to any of the current genera. For this reason, a new genus is proposed for this species.

Distribution
Only known from the type locality.

Discussion
The three new species and the new genus are an additional contribution to the knowledge of the morphological and taxonomic richness of land fl atworms of the Atlantic forest. Paraba tata sp. nov. fi ts well the genus in that its morphology compares well with the diagnostic features of the genus. In turn, Obama apiguara sp. nov. deviates from its congeners in that the eyes of this species are only monolobate and the penis papilla is provided with a small intra-papillar papilla. Furthermore, O. apiguara sp. nov. bears glandular fossae opening through the epidermic epithelium, a structure unknown in any other land planarian. Piima ata gen. et sp. nov. also presents unique features among Geoplaninae. Thus far, molecular markers have failed to reveal phylogenetic affi nities of this species with other taxa (Carbayo et al. 2013). Perhaps additional molecular markers or Next-Generation Sequencing (Álvarez-Presas & Riutort 2014), would give us a better understanding of the taxonomic affi nities of this new species and genus.