Eleutherodactylus michaelschmidi Díaz, Cádiz & Navarro, 2007, new species
Creators: name: Díaz, Luis M.
name: Cádiz, Antonio
name: Navarro, Nils
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Amphibia
Anura
Eleutherodactylidae
Eleutherodactylus
Eleutherodactylus michaelschmidi

description: Eleutherodactylus michaelschmidi, new species
Fig. 1 A–D
Holotype.— MNHNCu 975, an adult male from La Ceiba (20º11'07''N, 76º20'14''W), Municipality of Tercer Frente, Santiago de Cuba province, 408 m above the sea level, collected by Luis M. Díaz, Antonio Cádiz and Nils Navarro on October 11–12 of 2005.
Paratypes (n=19). — Males MNHNCu 976–981, with the same data as the holotype; MNHNCu 984, same locality but collected on October 8 of 2003 by Luis M. Díaz, Michael Schmid, Ana Sanz, Wolfgang Feichtinger and Claus Steinlein; MNHNCu 982–983, same locality, collected by Luis M. Díaz and Domenico Capolongo on April 30 of 2006; Females MNHNCu 985–987, and juveniles MNHNCu 988–991, with the same collecting data as the holotype. Females: BSC.H 150, Cueva de Rondón, Los Negros, Municipality of Contramaestre (20°15'N, 76°17'W), Santiago de Cuba, 160 m a.s.l., collected on April 16 of 1987 by Nicasio Viña Dávila; BSC.H 151, Cueva del Fogón, Loma del Ají (20°16'58''N, 76°19'28''W), Los Negros, 250 m a.s.l., same collector on April 14 of 1987; BSC.H 152, Cueva del Guanajo, Loma del Ají, Los Negros, Contramaestre, Santiago de Cuba, 250 m a.s.l., same collector on April 14 of 1987.
Diagnosis.— A large to medium size frog (females up to 48.1 mm SVL) of the subgenus Euhyas, more closely related to E. bresslerae (Fig. 1 E) than to any other taxon for the following combination of characters: similar size, conspicuous blotched pattern, laterally expanded digital discs, fourth finger disc’s proximal edge very close to the third finger disc base when both digits are held together, chirping calls, 16 pairs of chromosomes, and petricolous habits. Eleutherodactylus michaelschmidi has a more homogeneously blotched pattern throughout the body and extremities than E. bresslerae. In the latter species, blotches are larger and more densely grouped in the anterior half of dorsum, whereas they are smaller, more scattered, or even absent in the posterior part, on flanks, and legs. Typically, E. bresslerae has a reddish wash in the distal half of body which is absent in E. michaelschmidi. The new species also differs from E. bresslerae by having a relatively longer snout (43.9–49.1% of head length, x=46.8; versus 40.9–43.6%, x=42.3, in E. bresslerae), and proportionally smaller eyes (32.0–34.3%, x=33.0, of head length, vs. 36.0–38.5%, x=37.1, in E. bresslerae). There is also morphological and acoustic evidence that E. michaelschmidi is somewhat similar to E. ricordii (Fig. 1 F) and E. acmonis (Fig. 1 G), but differs from them essentially by its larger size (maximum SVL of 40 mm in females of E. ricordii and E. acmonis), enlarged digital discs (vs. smaller in the two other species), lighter belly (vs. typically fleshy gray in E. ricordii and E. acmonis), and by having a longer and higher snout (vs. short and gradually sloping in the two smaller species).
Description.— Head as wide as, or slightly longer than wide; length 40.6% (39.4–42.9) of SVL in males, and 40.3% (37.5–42.3%) in females; snout subacuminate in dorsal view, high in the middle point when seen in profile, overlapping the lower jaw; snout length 46.7% (43.9–49.1) of head length in males, and 45.0% (42.4–47.4%) in females; nostrils not protuberant, directed laterally, and separated by a distance equivalent to 21% (19–23%) of head width in males, and 22% (20–25%) in females; canthus rostralis slightly convex in dorsal view; loreal region almost vertical, slightly swollen, giving place to the labial margin by means a weak concavity that is more evident behind nares; lips not distinctively flared; interorbital distance 1.3% (1.1– 1.7%) times the upper eyelid width, without enlarged tubercles; eyelids skin with similar texture than dorsum; loreal area smooth or very slightly areolated; tympanum superficial, round, with distinct annulus, 59.6% (52.9–65.0%) of eye length in males, and 57.2% (53.2–64.9%) in females, separated from eye by a distance equivalent to 35.6% (31.1–45.6%) of its own diameter in males, and 39.9% (30.8–52.3%) in females; supratympanic fold distinct; postrictal tubercles numerous; choanae about 50–74% of third finger disc diameter, oval, not concealed by palatal shelf of maxillary arch; vomerine odontophores large, arched, forming definable angle, very narrowly separated each other, and only slightly extended beyond the external margins of choanae; tongue suboval, round or weakly notched behind, its posterior 3/4 not adherent to floor of mouth; external vocal sac absent, males only exhibit a small flat pouch when calling and have sublingual slits.
Skin areolate on dorsum and flanks; venter smooth; anal opening not extended in sheath; palmar tubercle oval or bifid, low, smooth, 1.1–1.4 times longer than thenar tubercle; supernumerary palmar tubercle commonly absent or inconspicuous; subarticular tubercles of fingers oval, prominent, rounded in profile or projected anteriorly; fingers length order: III> IV> II> I; digital discs well developed, laterally expanded, their diameter 38–66% of tympanum width; hands 26.6% (26.1–30.7%) of SVL in males, and 25.4% (24.4–27.0%) in females; heels without enlarged tubercles; inner metatarsal tubercle 2.3–3 times larger than the outer metatarsal tubercle, elliptical and smooth; supernumerary tubercles absent or inconspicuous; subarticular tubercles oval and moderately projected in profile; toes without defined lateral ridges or basal webbings; circumferential groove bordering the distal half of toe pad; heels overlaps when flexed legs are held at right angles to sagittal plane; toe length order: IV> V> III> II> I. Measurements are summarized in Table 1 together with those of the related species.
Color in life: Dorsum yellowish tan, with black blotches. Some individuals have larger blotches than others (Compares Fig. 1 A, B, and D), or only exhibit sparse mottling (Fig. 1 C). Many specimens show dorsolateral stripes defined by spaces between blotches. There is a broad loreal black stripe. Supratympanic fold black. Hands and feet gray. The iris is brown to reddish brown, lighter in the upper half than in the lower. The ventral surface is white.
Color in alcohol: White to whitish gray, with black, well contrasting blotches.
Advertisement call description and comparisons.— Eleutherodactylus michaelschmidi has complex vocalizations (Fig. 2 A, Table 2). The most commonly uttered signals are two note calls, together with chirps of 3–7 notes. Infrequently, frogs emit single note calls. Introductory calls (with a single note) are more intense than the remaining emissions, having an ill defined pattern of frequency modulation. The interval among introductory calls is 0.6–4.0 seconds (x=1.4). In the two note calls, the first signal is shorter and less intense than the second. Chirp notes have a slowly ascendant modulation of the frequency, lacking harmonics or having them weakly defined. Sporadic single note calls: 20–40 milliseconds (x=0.3). Notes interval (in two note calls): 62– 111 milliseconds (x=86). Call interval (including all types): 0.3–4.2 seconds (x=0.8). Chirp note intervals: 55– 78 milliseconds (x=70); note repetition rate: 15.7–17.5 notes per second. Call repetition rate: 19.7–103.5 calls per minute.
Advertisement calls of Eleutherodactylus bresslerae have never been described. This species emits a complex assemblage of sounds that are somewhat similar to those produced by E. michaelschmidi (Fig. 2 B, Table 2). Calls have 1 to 3 notes, mostly 2, and the whole sequence starts with 1–4 introductory calls (each one with one or two notes) that posses a higher intensity than the remaining emissions. Sporadically, chirps of 5–16 notes are inserted at the beginning of vocalizations, while in E. michaelschmidi they are more often intercalated. There are two types of two-note calls in which the first note is quite similar in both cases, but the second one exhibits more variation, with two modalities to be recognized: (1) an ascendant, convex shaped frequency modulation, with a complex harmonic structure, and (2) a sinuous modulation, with few harmonics. Both patterns are contrasting with the two note calls of E. michaelschmidi that keeps a slowly ascendant and slightly “concave” frequency modulation pattern, with an absent or less complex harmonic structure. The introductory calls and chirp notes of E. bresslerae are “hook shaped”, differing from the slowly ascendant pattern of E. michaelschmidi. E. bresslerae have higher values of dominant frequency than the new species, with the two-note calls longer and more spectrally complex (as shown in the Table 2). The interval among introductory calls of E. bresslerae is 73–852 milliseconds (x=672). Single note call duration: 48–57 milliseconds (x=52). Note interval (two note calls): 101–120 milliseconds (x=112). Call interval (including all types): 0.2– 3.7 seconds (x=0.9). Chirp note intervals: 46–58 milliseconds (x=52). Chirp note repetition rate: 18.7–19.8 notes per second. Call repetition rate: 82.8–121.0 calls per minute.
Calls of Eleutherodactylus acmonis and E. ricordii are hard to distinguish each other, and they are somewhat similar to those of E. bresslerae and E. michaelschmidi by having a chirping feature. In these two species, chirp notes have a faster ascendant frequency modulation and looks like vertical bars or “sticks” in the sonogram (Fig. 2 C, D). More commonly uttered calls consist of one or two notes. Introductory calls are usually very intense. Some spectral and temporal variables are summarized in Table 2.
Cytogenetic comparisons.— After conventional Giemsa staining, the chromosomes of Eleutherodactylus bresslerae and E. michaelschmidi can be arranged into 16 very similar (homologous) pairs (Fig. 3 a, a’). In both species the chromosome pair 1 is submetacentric, pair 2 is metacentric, and the remaining pairs 3–16 are telocentric or acrocentric showing a continuously decreasing length. In some metaphases, a secondary constriction can be detected in the paracentromeric region in the long arm of the chromosome pairs 1 (Fig. 3 a’). This karyotype pattern is very frequent among the Cuban species of Eleutherodactylus (Schmid et al., in preparation).
C-banding demonstrates the presence of darkly stained constitutive heterochromatin in the centromeric regions of all chromosomes in both species (Fig. 3 b, b’). Additionally, distinct interstitially C-bands are present in the paracentromeric regions of the longs arms of the pairs 13. More faintly stained constitutive heterochromatin can be detected in the paracentromeric region in the long arms of chromosome pairs 1, and in the telomeric regions in the long arms of all chromosomes. Comparison of the C-band patterns in both species exhibits slight but distinct differences. In the chromosomes of E. bresslerae the centromeric heterochromatin is more prominent than in those of E. michaelschmidi. Furthermore, in the chromosome pairs nos. 4, 6 and 12 of E. bresslerae prominent interstitial C-bands are located in the paracentromeric regions of the long arms that are absent in the karyotype of E. michaelschmidi.
Silver labeling demonstrates that in both species the nucleolus organizer regions (NORs) are located in the secondary constriction in the paracentromeric region of the long arms of chromosome pairs 1 (Fig. 3 c, c’). The same result was obtained by fluorescence counterstaining with distamycin A/mithramycin (not shown).
The most significant cytogenetic difference between E. bresslerae and E. michaelschmidi is elucidated by fluorescence staining with quinacrine mustard (Fig 4). Whereas all chromosomes of E. bresslerae exhibit a uniform fluorescence without any brightly fluorescing bands (Fig. 4 a), in E. michaelschmidi the telomeric heterochromatin in the long arms of chromosome pairs 7, 9, and 11 of is distinguished by an extremely bright fluorescence (Fig. 4 a’). These quinacrine positive telomeric chromosome regions are visible in the interphase cell nuclei of E. michaelschmidi as very brightly fluorescing chromocenters (Fig. 4 b). It is well known that AT base pair-rich DNA sequences enhance the intensity of quinacrine fluorescence, whereas GC base pair-rich quench this fluorescence (Weisblum and de Haseth, 1972; Weisblum, 1973). Therefore, it can be concluded that the six quinacrine positive heterochromatic telomeric regions present in the karyotype of E. michaelschmidi consist of AT-rich highly repetitive DNA sequences. Such AT-rich heterochromatic regions are not rare in amphibian genomes (Schmid, 1980; Schmid et al., 1990).
Heteromorphic sex chromosomes were neither detected in the single male individual of E. michaelschmidi analyzed, nor in the three males and four females of E. bresslerae. The microscopic analysis of the male meiotic chromosomes in the stage of diakinesis did not contribute to the differentiation between E. bresslerae and E. michaelschmidi. In the two species the 16 bivalents have either a ring-like pairing configuration showing terminal chiasmata on both ends, or a rod-like form in which the chiasmata at one end of the bivalents have already been opened, whereas the chiasmata of the opposite end of the bivalents are still maintained.
Distribution.— Eleutherodactylus michaelschmidi is known from La Ceiba (type locality), Municipio Tercer Frente, and the region of Los Negros, Municipio Contramaestre, both localities in the karstic valleys and premontane areas at the north slope of Sierra Maestra, Santiago de Cuba Province (Fig. 5).
Etymology.— We take pleasure in naming this species for Dr. Michael Schmid from the Biocenter of the University of Würzburg (Germany), a worldwide authority in amphibian chromosomes and good friend. In 2003, Dr. Schmid and colleagues organized a joint expedition with the Universidad de La Habana and the Museo Nacional de Historia Natural de Cuba in which the new frog was collected for the first time.
Natural History.— The limestone mountains and premontane valleys inhabited by Eleutherodactylus michaelschmidi are covered by secondary vegetation and the remnants of a semideciduous forest. Many places (like the type locality) are widely used for coffee plantations. Specimens were found at night (21:00– 1:00 hours), mostly on rocky surfaces and cave entrances (Fig. 6), but two individuals were seen on fallen trunks. Stomach content of several of these frogs revealed ants of the genera Camponotus and Odontomachus (in most of stomachs), cockroachs, crickets, beetles (a curculionid, an elaterid, carabids: Aspidoglossa mexicana), an opilion, and many acari. Other anuran species at the type locality and their surroundings were: Bufo peltocephalus, B. taladai, Osteopilus septentrionalis, Eleutherodactylus atkinsi, E. auriculatus, E. cuneatus, E. ionthus, E. leberi, E. ronaldi, and E. varleyi.
Cuban rock/cave dwelling frogs: comments and comparisons Extreme morphological tendencies among the rock/cave dwelling frogs are the developing of laterally expanded digital discs (larger in the two external fingers), large eyes, and relatively longer legs and digits (Hedges, 1989), as present in Eleutherodactylus michaelschmidi. The largest members of the genus in Cuba are rock/cave dwellers; smaller frogs, like E. planirostris, E. goini, E. ricordii, E. acmonis, E. zugi, and few others, are opportunistic of several karstic situations that provide them many shelters and high humidity, but they are also present in other terrestrial habitats. Eleutherodactylus guanahacabibes and E. tonyi apparently evolved in a karstic environment, but are somewhat similar to the widespread E. planirostris in appearance. Eleutherodactylus klinikowskii, an inhabitant of the prominent limestone areas of the Sierra de los Órganos (Western Cuba), is morphologically similar to E. zugi, a species that frequents the leaf litter of forests (although E. zugi erythroproctus is associated with a karstic habitat). Eleutherodactylus etheridgei also occurs in limestone outcrops, marine terraces, and small volcanic mountains along the semidesertic south coast of Guantánamo and Santiago de Cuba, sharing its general aspect with many ground dwelling frogs. None of these small species (15–30 mm of maximum SVL) have the extreme morphologies mentioned above for the largest rock/cave dwelling congeners and show only poor to moderate development of digital discs. Most of the Cuban rock/cave dwelling frogs have smooth bellies (except E. klinikowskii and E. zugi, with a weakly areolate venter), and a granular to strongly tuberculate dorsal skin. The majority of the larger species were considered “mute” by Schwartz and Henderson (1991), but all of them vocalize actively under proper conditions even in a very intense way as described bellow.
Eleutherodactylus bresslerae and E. michaelschmidi are allopatric species. The occurrence of E. bresslerae has been only confirmed for the region of the mouth of the Yumurí River, Baracoa, Guantánamo (Schwartz and Henderson, 1991), 215 km (aerial distance) from the type locality of E. michaelschmidi. In the context of the large Cuban rock dwelling frogs (most exceeding 30–40 mm of SVL), E. michaelschmidi must be also compared with other species in the E. ricordii group having mottled, spotted, or marbled coloration patterns: E. thomasi (Fig. 1 H), E. blairhedgesi (Fig. 1 I), E. greyi (Fig. 1 J), E. pezopetrus (Fig. 1 K), and E. pinarensis (Fig. 1 L).
Eleutherodactylus thomasi and E. blairhedgesi, are two closely related species with a more diffuse and less conspicuous mottled pattern than E. michaelschmidi, having contrasting pairs of blotches in the suprascapular region and middorsum that frequently defines a “W” or an inverted “V” figure. E. thomasi is represented by three subspecies (Schwartz and Henderson, 1991) none in the distributional range of E. michaelschmidi: E. thomasi thomasi (Sierra de Cubitas and Sierra de Najasa, Camagüey province; with populations closely related to this taxon in Caguanes, Cayo Coco, and Gibara that still need revision), E. thomasi trinidadensis (south slope of Macizo de Guamuhaya, Central Cuba), and E. thomasi zayasi (Sierra de Camarones and Pan de Matanzas, provinces of La Habana and Matanzas, respectively). E. blairhedgesi is only known from two localities in the north coast of La Habana: Canasí (Estrada et al., 1997) and Puerto Escondido. In E. blairhedgesi, calls are very complex, intercalating emissions of one or two notes with intense trills of 3–5 notes (Fig. 7A). One note calls are more frequently uttered, with duration of 20–67 milliseconds. Trills last 76–255 milliseconds, depending on notes number. Notes have different frequency modulation patterns: ascendant, descendant, sinuous, inverted “U” shaped, or they are ill modulated. Calls of E. thomasi zayasi (Fig. 7B) are also complex assemblages of one, two or more notes. Sporadically there are intense trills up to seven short notes. Notes have frequency modulation patterns as defined for the previous species. See Table 3 for general comparisons.
Differing from E. michaelschmidi, E. greyi have a darker coloration and stippling pattern. The distribution of E. greyi comprises moderate to high elevations of Central Cuba (Schwartz and Henderson, 1991). In this species, more frequently uttered calls have two notes, but no chirps have been ever recorded (Fig. 7C). The first note is shorter than the second, being less intense, having typically two harmonics, and lacking frequency modulation. First note frequency is lower than the second one. The last note has an ascendant pattern of frequency modulation. Individual calls are sporadically emitted, which are somewhat similar to the second notes. Values for some acoustic variables are summarized in Table 3. Eleutherodactylus greyi is not a strictly rock/ cave dwelling frog and, besides these habitats, adults and juveniles are found in the forest leaf litter and river talus.
Eleutherodactylus pezopetrus is definitely a poorly spotted frog, with a very different appearance than E. michaelschmidi. Individuals of E. pezopetrus exhibit dorsolateral stripes, a marbled pattern and/or two lateral pale blotches at midbody. Patterns of E. pezopetrus are more similar to those of E. cuneatus (a riparian frog that also inhabits either forest floor or rocky situations), than to any other Cuban species. This species inhabits the karstic mountains that arise from the south slopes of Alturas de Nipe to the north part of Meseta del Guaso, in the provinces of Santiago de Cuba and Guantánamo (Cantera J. A. Mella in Santiago de Cuba, and Farallones del Río Cuzco in Guantánamo). Vocalizations are complex assemblages of one to three note calls (usually two), with a typical rhythm (Fig. 7D). Introductory calls are more intense and usually have three notes. Notes may lack spectral modulation or have either an ascendant, descendant, or “U” shaped pattern. Some temporal and spectral variables are summarized in Table 3.
Contrasting with Eleutherodactylus michaelschmidi, E. pinarensis is a big, robust frog, with blotches and dark areas arranged transversally alternating with paler zones. Loreal dark stripes are absent in adults. In juveniles, a light transverse band is generally conspicuous at midbody, a pattern never reported for other Cuban frogs. This species is irregularly distributed along karstic habitats in the western part of Cuba (Estrada and Novo, 1985; Schwartz and Henderson, 1991). E. pinarensis emits a complex assemblage of signals with a typical rhythm, alternating calls of one or two notes with intense trills of 4–11 notes (Fig. 7E). Trill notes are arranged in a descendant order of frequency (from a maximum of 3.9 kHz to a minimum of 2.1 kHz). More commonly uttered calls contain two notes. Generally, the first note is shorter than the second. Trills last 135– 300 milliseconds, depending on the number of notes, and seems to have a strong territorial function considering male choruses start vigorous after first trills uttering. Signals, other than trills, are typically ascendant (only few are descendant) modulated in frequency or sporadically lacks modulation. See Table 3 for some acoustic data of this species.
Species (N) Notes per Call duration Call interval Call rate Dominant
call (mode) (milliseconds) (seconds) (calls/minute) frequency (kHz)
E. blairhedgesi (3) 1–2 (1) I: 20.4–67.9 0.6–20.7 69–101 1.9–5.7 II: 104.7–922.3
Eleutherodactylus michaelschmidi does not need comparison with the two species within the E. symingtoni group: E. symingtoni (Fig. 1 M) and E. zeus (Fig. 1 N). They are the largest Cuban frogs of the genus (50– 90 mm SVL). E. zeus occurs in the Cordillera de Guaniguanico, Pinar del Río province; E. symingtoni, besides this mountain range, also inhabits lowlands of Artemisa and the Sierra de Camarones (La Habana province) (Schwartz and Henderson, 1991; Rodríguez and Alonso, 2006). Both species are unique by having the combination of (character status of E. michaelschmidi in parenthesis): a triangular prominence behind the eyes which covers the short, out-turning and pointed zygomatic ramus of the squamosal bone (vs. absent); very high tympanum (vs. only slightly higher than wide); short vomerine odontophores (vs. long); exostosed frontoparietals (vs. no exostosed); and prominent canthal tubercles (vs. absent). E. symingtoni and E. zeus are strongly tuberculated frogs (especially the first species), plain colored or with patterns that differ from those exhibited by E. michaelschmidi. Advertisement calls of E. symingtoni and E. zeus have never been described. Both taxa emit the lowest frequencies among all Cuban species of the genus (Fig. 7 F, G). Table 3 summarizes some acoustic variables of these species. Vocalizations comprise mostly single note calls with a variably complex harmonic structure uttered at a relatively low repetition rate. When approached, males of E. symingtoni change the homogeneously produced one note calls for two note calls (Fig. 7F), heterogeneous call sequences, or by a sporadic whistle (421–667 milliseconds, and 0.9–1.5 kHz). Males of E. zeus also switch the typical single note calls to multinote calls when disturbed. Caught individuals of this species may emit an intense distress call with a duration of 0.9–1.6 seconds, a dominant frequency of 1.7–3.2 kHz (x=2.6 kHz), and a complex harmonic structure (Fig. 7G).
description: Published as part of Díaz, Luis M., Cádiz, Antonio & Navarro, Nils, 2007, A new rock dwelling frog of the genus Eleutherodactylus (Amphibia: Leptodactylidae) from Eastern Cuba, with comments on other species with similar habits, pp. 51-68 in Zootaxa 1435 on pages 52-65, DOI: 10.5281/zenodo.175853