Albericus murritus, Kraus & Allison, 2009

Kraus, Fred & Allison, Allen, 2009, New microhylid Frogs from the Muller Range, Papua New Guinea, ZooKeys 26 (26), pp. 53-76 : 55-57

Albericus murritus sp. n.

urn:lsid:zoobank.org:act:C1F51397-8A1C-404B-AAF5-2B68F46C6A53

Fig. 1A

Holotype. BPBM 33657 (field tag FK 13097 ), collected by F. Kraus, S of Tumbutu River , Muller Range, 5.6567028°S, 142.6342342°E, 1700 m, Southern Highlands Province, Papua New Guinea, 2 April 2009.

Paratypes (n = 31). BPBM 33636–40 , Kunida , Muller Range, 5.6431159°S, 142.6342342°E, 1700 m, 21–22 March 2009 ; BPBM 33641 , E slope Mt. Itukua , Muller Range, 5.66954°S, 142.62334°E, 2177 m, 27 March 2009 ; BPBM 33642– 53 , Tumbutu River below Mt. Paramo, 5.6503623°S, 142.63963°E, 31 March 2009 ; BPBM 33654–56 , same data as BPBM 33642–53 except collected 1 April 2009 ; BPBM 33658 , PNGNM 24095–96 , same data as holotype ; BPBM 33659 , PNGNM 24093–94 , Mt. Paramo , 5.64545°S, 142.63904°E, 1777 m, 2 April 2009 ; BPBM 33660–63 , same data as BPBM 33642–53 except collected 2 April 2009 .

Diagnosis. A small species (adult SV = 14.6–18.3 mm) distinguished by its combination of oblique lores, distinct tympanum, relatively broad snout (IN/SV = 0.081 – 0.096, mean 0.086), relatively wide finger discs (3rdF/SV = 0.059 –0.081), and advertisement call consisting of a single peep uttered in a continuous series.

Comparisons with other species. The new species differs from all congeners except A. swanhildae Menzies and A. exclamitans Kraus and Allison in having a call

Figure |. Photos in life of A paratype of Albericus murritus sp. n. (BPBM 33656) B paratype of Cophixalus caverniphilus sp. n. (BPBM 33711) C paratype of Oreophryne anamiatoi sp. n. (BPBM 33764), and D paratype of Oreophryne anamiatoi sp. n. (BPBM 33765).

consisting of a peep; all other Albericus have calls consisting of a single honk/buzz or a series of clicks. From A. swanhildae the new species differs in its larger size (SV = 13.6–15.4 mm in A. swanhildae ), oblique (vs. vertical) lores, wider finger discs (3rdF/ SV = 0.055 –0.061 in A. swanhildae ), and in having a single broad dark band across the center of each shank (vs. three narrow dark bars across each shank in A. swanhildae ). From A. exclamitans the new species differs in having the tympanum evident (vs. hidden) in males and in having the call consist of an infrequently produced single peep (vs. rapid burst of 3–48 peeps in A. exclamitans ). Albericus murritus is also slightly smaller than A. exclamitans (male SV = 14.6–18.3 mm, female SV = 15.0– 18.3 mm in A. murritus vs. 15.3–20.7 and 18.0–22.0 in A. exclamitans ) and has a somewhat broader snout (IN/SV = 0.074 –0.085, mean 0.079 in A. exclamitans ).

Description of holotype. Adult male. Head relatively wide (HW/SV = 0.38), with oblique and shallowly concave loreal region; canthus rostralis broadly rounded; nostrils small, crescent-shaped, much closer to tip of snout than to eyes; distance from external naris to eye larger than internarial distance (EN/IN = 1.14, IN/SV = 0.083, EN/SV = 0.095); snout bluntly rounded when viewed from above, truncate when viewed from side; eyes moderately large (EY/SV = 0.13), eyelid approximately 2/3 width of interorbital distance; tympanum indistinct, partially hidden by surrounding skin. Dorsum pustulose on body and limbs; supratympanic fold absent but row of dorsal pustules occupy that area; ventral surfaces coarsely granular. Fingers unwebbed, bearing discs with terminal grooves; relative lengths 3>4>2>1. Finger discs approximately twice widths of penultimate phalanges. Subarticular tubercles not well developed; metacarpal tubercles absent. Toes unwebbed, bearing discs with terminal grooves; relative lengths 4>5>3>2>1. Toe discs smaller than those of fingers (3rdF/4thT = 1.24), approximately 1.5 times width of penultimate phalanges. Subarticular tubercles low; metatarsal tubercles lacking. Hind legs rather short (TL/SV = 0.40); arms rather long (ArmL/SV = 0.54).

In preservative, dorsal ground color an irregular mix of yellow-tan and brown, with the former predominating dorsolaterally and the latter mid-dorsally; parts of both fields suffused with russet. Irregular black flecks and markings scattered throughout, concentrated above shoulders, on rear of head, and above tympana. Traces of a short, lighter, yellow-brown bar on each scapula; similar-colored interocular bar and vestiges of lumbar ocelli. Sides dark gray flecked with black and light blue-gray. Face yellow-tan flecked with black and russet. Legs yellow-tan with one broad, dark, centrally placed band on each thigh and shank. Rear of thighs dark brown with narrow yellow-tan band proximally. Venter dirty light gray evenly and densely peppered with dark gray; palmar and plantar surfaces same. Front margin of mandible russet. Iris black flecked with silver.

Variation. Mensural variation for the type series is shown in Table 1. Th ere is no obvious sexual dimorphism in morphometric features, although there is slight evidence that females may average larger in body size. However, this difference is slight considering the normal pattern of larger female size in most Papuan frogs.

Most specimens appear dark brown in preservative (darker than the holotype), with a few contrasting light-brown streaks or lines scattered on dorsum. These typically involve a single short line on each scapula, an interocular bar, and often traces of lumbar ocelli. Lighter specimens are similar but show more clearly the variable mottling seen in the holotype. Density of dark ventral stippling varies from sparse to dense, making the overall appearance of the venter vary from light gray to black. Both ventral extremes appear in frogs with both light and dark dorsa, but venters of frogs that are lighter dorsally average somewhat paler than those of dark frogs.

Color in life. BPBM 33636: “Dorsum dark tan with irregular black blotches and tiny white or tan dots on some warts; fairly warty. Orange-brown interocular bar, suprascapular marks, and on arms and heels. Venter charcoal gray with tiny light-gray punctations. Light-tan patch from eye to rictus. Iris brown.” BPBM 33637 was yellow-brown with cream and black markings, venter densely punctated with light gray, and iris tan.

Call. This species begins calling at dusk and calls in highest numbers during the first few hours of darkness. Th e call consists of a single “peep” note uttered in a continuous series with occasional breaks ( Fig 2 ). We recorded calls of two individuals, BPBM 33641 and BPBM 33657 ( Table 2). The notes had a mean duration of 0.151 s (range 0.093 –0.213). The inter-note interval for BPBM 33641 ranged from 4.1– 9.0 s (n = 20), except for two instances of 31.6 and 35.9 s. Many species of Albericus produce calls in groups separated by periods of silence (A. Allison, pers. obs.), and our brief recording suggests that this is occurring in BPBM 33641.

Figures

Figure 2. A Waveform, B power spectrum, and C spectrogram of call “T” of Albericus murritus sp. n. (BPBM 33641) recorded on E slope Mt. Itukua, Muller Range, Southern Highlands Province, Papua New Guinea on 27 March 2009 at 2020 h. Air temperature 14.7 °C.