Megophrys acuta Wang, Li and Jin

Li, Yu-Long, Jin, Meng-Jie, Zhao, Jian, Liu, Zu-Yao, Wang, Ying-Yong & Pang, Hong, 2014, Description of two new species of the genus Megophrys (Amphibia: Anura: Megophryidae) from Heishiding Nature Reserve, Fengkai, Guangdong, China, based on molecular and morphological data, Zootaxa 3795 (4), pp. 449-471 : 453-463

Megophrys acuta Wang, Li and Jin sp. nov.

Holotype. SYS a002267, adult male, collected on 15 August 2013 by Yu-Long Li (YLL hereafter), Kai Chen (KC hereafter) and Ying-Yong Wang (YYW hereafter) from Heishiding Nature Reserve ( HNR hereafter) (23°28'27" N, 111°53'53" E; 277.1 m a.s.l.), Fengkai County, Guangdong Province, China. ( Figure 3 )

Paratypes. 14 specimens (9 adult males, four adult females, one juvenile), from HNR at elevations between 277.1–433.6 m a.s.l.. SYS a002266–2269, 2276, adult males, collected on 13–20 August 2013 by YLL, KC, Zu- Yao Liu (ZYL hereafter) and YYW; SYS a002159, adult male, collected on 2 June, 2013 by YLL; SYS a001957, adult male, collected on 12 November, 2012 by Run-Lin Li (RLL hereafter); SYS a002278, adult male, collected on 28 June, 2012 by YYW; SYS a000165, 0 169, adult males, collected on 2 May, 2008 by Jian-Huan Yang (JHY hereafter) and YYW; SYS a000517, adult female, collected on 28 May, 2009 by JHY; SYS a000521, adult female, collected on 5 April, 2009 by JHY; SYS a000187, adult female, collected on 29 May, 2008 by JHY and YYW; SYS a000168, adult female, collected on 2 May, 2008 by JHY and YYW; SYS a002274, juvenile, collected on 20 August 2013 by ZYL and YYW.

Diagnosis. Megophrys acuta sp. nov. is characterized by the combination of following characters: (1) A slender and small-sized species measuring 28.1–33.6 mm in snout-vent length (SVL) in adult females, 27.1–33.0 mm in SVL in adult males; (2) head width slightly larger than head length; (3) snout remarkably pointed in dorsal view, strongly projecting, sloping backward to mouth in profile, protruding well beyond margin of lower jaw; (4) canthus rostralis well developed; (5) tympanum great and distinct; (6) no vomerine teeth; (7) margin of tongue smooth, not notched behind; (8) the heels not meeting; (9) tibio-tarsal articulation reaches forward the pupil of eye; (10) tibia relatively short, 0.38–0.45 of SVL; (11) relative finger length I <II ≤ IV <III; (12) toes with weak lateral fringes, and fleshy webs at their bases; (13) distinct subarticular tubercle at the base of each finger; (14) dorsal skin smooth with scattered granules and a few tubercles, some of which form a X-shaped ridge and two discontinuous dorsolateral ridges on either side of the X-shaped ridges on back of trunk; (15) a horn-like, remarkably prominent tubercle at the edge of the eyelid; (16) dorsal surface brown, with an incomplete dark triangle between eyes and a rectangular dark marking on the center of the back of trunk; (17) forearm with a distinct black transverse band; (18) hindlimbs with 3–5 incomplete black transverse bands; (19) nuptial pad weak, no nuptial spines in adult males; (20) single vocal sac in males; (21) gravid females bear pure yellowish oocytes.

Comparisons. Megophrys acuta sp. nov. is here compared with 46 recognised species of genus Megophrys occurring from the India, Indo-China Peninsula to China, except M. montana and M. nasuta . Comparative data are shown in Table 3 .

TABLE 2. Uncorrected p-distances among the Megophrys species studied, based on a 16S rRNA fragment.

M. spinata .

……continued on the next page M. acuta sp. nov. is a sister taxon to M. brachykolos in our phylogenetic tree, and differs from latter (in parenthesis) by its snout pointed (vs. almost truncate); inner metacarpal tubercle, outer metacarpal tubercle and inner metatarsal orange-red, tip of digits pale grey tinged pinkish (vs. all pale grey); subarticular tubercles absent (vs. present); the region around cloaca smooth, with scattered small granules (vs. with heavy tubercles, one on each side of cloaca large, pointed); horn-like tubercles slightly large, remarkably prominent at edge of upper eyelids (vs. small); lateral fringes present (vs. absent); nuptial spines absent in adult males (vs. present).

M. acuta sp. nov. differs from M. kuatunensis and M. minor , which were reported to occur in Heishiding Nature Reserve (in parenthesis) by snout pointed (vs. obtusely rounded); horn-like tubercles slightly large, remarkably prominent at edge of upper eyelids (vs. small, indistinct); margin of tongue not notched (vs. notched); nuptial spines absent in adult males (vs. present). Further, new species differs from M. kuatunensis by its tibiotarsal articulation reaching forward the pupil of eye, when hindlimb is stretched along the side of the body (vs. reaching the region between tympanum and eye); from M. minor by shank short, TIB (tibial length) / SVL ratio 0.38–0.45 (vs. 0.49); the heels not meeting when the hindlimbs are flexed and the thighs are held at right angles to the body axis (vs. meeting or overlapping); lateral fringes present (vs. absent).

M. acuta sp. nov. has a small body size with maximum SVL 33.6 mm in adult individuals, and can be distinguished from the following 24 congeners with minimum SVL> 40 mm: M. aceras Boulenger , M. ancrae Mahony, Teeling & Biju (SVL> 39 mm), M. auralensis Ohler, Swan & Daltry , M. baolongensis Ye, Fei & Xie ,, M. binlingensis Jiang, Fei & Ye , M. caudoprocta Shen , M. damrei Mahony , M. gigantica Liu, Hu & Yang , M. glandulosa Fei, Ye & Huang , M. jingdongensis Fei & Ye , M. lekaguli Stuart, Chuaynkern , Chan-ard & Inger, M. longipes Boulenger , M. major Boulenger , M. mangshanensis , M. medogensis Fei, Ye & Huang , M. megacephala Mahony, Sengupta, Kamei & Biju , M. nankiangensis Liu & Hu , M. omeimontis , M. robusta Boulenger , M. sangzhiensis Jiang, Ye & Fei. , M. shapingensis Liu , M. shuichengensis Tian, Gu & Sun , M. spinata and M. takensis Mahony.

From the remaining 19 small-sized congeners with SVL shorter than 40 mm, M. acuta sp. nov. can be steadily distinguished by the combination of following characters: Hindlimbs short, its heels not meeting when the hindlimbs are flexed and the thighs are held at right angles to the body axis vs. relatively long, heels meeting or overlapping in M. binchuanensis Ye & Fei , M. boettgeri , M. cheni , M. daweimontis Rao & Yang , M. huangshanensis , M. jinggangensis , M. lini , M. oropedion Mahony, Teeling & Biju , M. pachyproctus Huang , M. palpebralespinosa Bourret , M. parva (Boulenger) , M. tuberogranulatus Shen, Mo & Li , M. vegrandis Mahony, Teeling & Biju , M. wawuensis Fei, Jiang & Zheng , M. wuliangshanensis Ye & Fei , M. wushanensis Ye & F ei, M. zhangi Ye & Fei ; horn-like tubercles slightly large, remarkably prominent at edge of upper eyelids vs. small, indistinct or absent in M. binchuanensis , M. boettgeri , M. cheni , M. daweimontis , M. huangshanensis , M. lini , M. oropedion , M. pachyproctus , M. parva , M. tuberogranulatus , M. wawuensis , M. wuliangshanensis and M. wushanensis , and M. zhangi ; vomerine teeth absent vs. present in M. daweimontis , M. jinggangensis , M. oropedion , M. pachyproctus , M. palpebralespinosa , M. parva , M. serchhipii (Mathew & Sen) , M. zhangi , M. zunhebotoensis (Mathew & Sen) ; margin of tongue not notched vs. notched in M. boettgeri , M. cheni , M. huangshanensis , M. oropedion , M. pachyproctus , M. vegrandis , M. wawuensis and M. zhangi ; lateral fringes minute, narrow on toes vs. wide in M. cheni , M. lini , M. binchuanensis , M. boettgeri , M. palpebralespinosa , M. wushanensis (in males), and lacking lateral fringes in M. daweimontis , M. huangshanensis , M. oropedion , M. pachyproctus , M. parva , M. tuberogranulatus , M. wawuensis , M. wuliangshanensis , M. wushanensis (in females); shank short, TIB / SVL ratio 0.38–0.45 vs. 0.50–0.54 in M. cheni , 0.54 in M. daweimontis , 0.47–0.50 in M. jinggangensis , 0.46–0.53 in M. lini , 0.49 in M. pachyproctus and M. zhangi , 0.55 in M. palpebralespinosa , 0.48–0.53 in M. parva , 0.45–0.51 in M. tuberogranulatus , 0.49–0.54 in M. vegrandis , 0.51–0.59 in M. wawuensis , 0.50–0.51 in M. wuliangshanensis , 0.47–0.48 in M. wushanensis , 0.46–0.50 in M. zunhebotoensis ; tympanum great, distinct, tympanum diameter (TMP) / eye diameter (EYE) ratio 0.57–0.71 vs. small or indistinct in M. cheni (0.41–0.54), M. binchuanensis (0.33–0.50), M. huangshanensis (<0.5), M. pachyproctus (0.29), M. palpebralespinosa (tympanum small), M. parva (0.4), M. serchhipii (0.39), M. tuberogranulatus (0.50), 0.44–0.56 in M. vegrandis , M. wawuensis (0.33), M. wuliangshanensis (0.50), wushanensis (0.50) and M. zhangi (0.50); nuptial spines absent in adult males vs. present in M. binchuanensis , M. boettgeri , M. huangshanensis , M. lini , M. oropedion , M. pachyproctus , M. palpebralespinosa , M. tuberogranulatus , M. wawuensis , M. wuliangshanensis , M. wushanensis , M. zhangi .

Description of holotype. An adult male individual. Body slender and small with 32.2 mm in SVL; head length (HDL) slightly shorter than head width (HDW), HDW/HDL ratio 1.07; snout pointed in dorsal view, strongly projecting, sloping backward to mouth in profile, protruding well beyond margin of lower jaw; top of head flat; eye large, EYE 35% of HDL, pupil vertical; nostril oblique ovoid with low flap of skin laterally; canthus rostralis sharp, well developed; loreal region vertical, not concave; internasal distance ( IND) larger than interorbital distance (IOD); tympanum great, distinctly visible, TMP/EYE ratio 0.68; tympanum-eye distance (TEY) small, TEY 1.6 mm, TEY/TMP ratio 0.64; choanae large, ovoid at the bases of the maxilla; two vomerine ridges weak, no vomerine teeth; margin of tongue smooth, not notched behind.

Forelimbs moderately slender; radioulna length (RAD) 25% of SVL, hands without web, moderately longer, hand length (HND) 24% of SVL; fingers slender, no lateral fringes, relative finger length I <II ≤ IV <III; tips of digits round, slightly dilated; a large subarticular tubercle at the base of each finger; thumb with weak nuptial pad, and without nuptial spines; two metacarpal tubercles well developed, inner one significantly enlarged. Hindlimbs moderate, slightly robust; tibio-tarsal articulation reaches forward the pupil of eye, when hindlimb is stretched along the side of the body; the heels not meeting when the flexed hindlimbs are held at right angles to the body axis; tibia length (TIB) 42% of SVL; foot length (FTL) 55% of SVL; relative toe lengths I <II <V <III <IV; tips of toes round, slightly dilated; toes with a fleshy web at their bases; subarticular tubercles absent; lateral fringes weak; external tarsal fold present; inner metatarsal tubercle long ellipsoid; outer metatarsal tubercle absent.

Skin on all upper surfaces smooth, with scattered granules and several tubercles, some of which arranged in an X-shaped ridge on back and two discontinuous dorsolateral parallel ridges on either side of the X-shaped ridge; a horn-like tubercle at the edge of the eyelid remarkably prominent; supratympanic fold distinct, curving posteroventrally from posterior corner of eye to a level above insertion of arm; several tubercles scattered on flanks, and on dorsal surfaces of thighs and forearms; ventral surface smooth, with small granules on throat and chest, posteriorly heavy covered with pustules and small granules on belly, ventral side and rear of thighs; external tarsal fold with several large pustules; the region around cloaca smooth, with scattered granules; pectoral gland large, round, prominently elevated relative to ventral surface, closer to axilla than to mid-ventral line; single larger femoral gland on rear of thigh, two small lip glands on anterior part of lower jaw; cloacal opening unmodified, directed posteriorly, at upper level of thighs.

Measurements of holotype (in mm). SVL 32.2, HDL 10.5, HDW 11.2, SNT (snout length) 4.4, IND 3.5, IOD 3.3, EYE 3.7, TMP 2.5, TEY 1.6, HND 7.8, RAD 8.2, FTL 17.8, TIB 13.4.

Coloration of holotype in life. Red-brown above, with scattered black spots; an incomplete dark triangle between the eyes; an X-shaped dark marking along X-shaped ridge, in the region around intersection of which becoming distinct, dark oblong shape; forearm with a distinct, black oblique band; dorsum of II and III fingers black; hindlimbs with black spots, forming three broken black transverse bands; tip of snout dark brown; a dark brown vertical band under the eye; supratympanic fold light-colored; horn-like, remarkably prominent tubercles white. Lower lip dark brown with white crossbars. Ventral surface reddish brown; a longitudinal dark brown streak down the center of the throat and chest; the central region of posterior belly with black and white blotches, two broad grey-brown mottlings with black borders on either side of belly; ventral surface of limbs marbled white on dark brown; external tarsal fold light brown; the palms and soles dark brown, inner metatarsal tubercle and outer metacarpal tubercle orange-red, tip of digits reddish; pectoral glands white; femoral glands white. Pupil black; iris brown with black fine lines.

Coloration of holotype in preservative. Red-brown fades to greyish-brown on dorsal surface, scattered black spots; grey-black triangle between the eyes and X-shaped marking become more distinct; ventral surface is paled in color: orange faded, ventral ground color grey-brownish with small dark spots, patches and a longitudinal dark brown streak.

Variation. Measurements and body proportions of type series are given in Table 4 .

All 14 specimens (ten males, three females, one juvenile) were very similar in morphology and color pattern. In female individuals (SYS a000168, 0 187 and 0521), snout slightly pointed; the horn-like conical tubercles at the edges of the eyelids were relatively prominent; black transverse bands on dorsal hindlimbs relatively complete. In juvenile individual (SYS a002274), upper surface light brown, tinged greyish; its body size small measuring 17.6 mm in SVL.

Secondary sexual characteristics. M. acuta sp. nov. shows no obvious differences in body size between males (SVL: 30.9±1.87, 27.1–33.0mm, N=10) and females (SVL: 31.6±2.56, 28.1–33.6mm, N=4); adult males have a single subgular vocal sac and weak nuptial pads, lack of nuptial spines.

Etymology. The specific epithet “ acuta ” is a Latin adjective (pointed, sharp), referring to the snout pointed and canthus rostralis sharp. We propose the standard name “Fengkai’s Horn Toad”, Chinese name “Feng Kai Jiao Chan”.

Distribution and habits. Currently, M. acuta sp. nov. is known only from the type locality, Heishiding Nature Reserve, and the adjoining Qixing Nature Reserve, Fengkai County, Guangdong Province, China. It inhabits forest floor, leaf litter and the nearby undergrowth mountainous streams surrounded by moist subtropical evergreen broadleaved forests at elevations between 270– 450 m. ( Figure 4 . A)

Advertisement calls. We recorded the calls of male holotype SYS a002267 from the bank of the streamlet, and the ambient air temperature which was 26.9°C. The sonograms and waveforms are shown in Figure 5. We define a continuous vocalization with pauses less than one second as a strophe. One strophe consists of a series of syllables of a pulsed structure. The call consists of a few strophes of 3.440– 4.649 s duration (mean 4.202 ± 0.460, N = 4). Each strophe contains 7–9 syllables (mean 8.250 ± 0.829, N = 5). Each syllable has a duration of 0.106– 0.172 s (mean 0.136 ± 0.012, N = 33). The interval between syllables has a duration of 0.335– 0.747 s (mean 0.425 ± 0.092, N = 29). Syllables are repeated in series at a rate of 1.87–2.04 times (mean 1.967 ± 0.066, N = 4) per second.

Syllable-intervals gradually increase from the beginning to the end of each strophe. Amplitude modulation within syllables is unapparent, only increasing slightly to a maximum by approximately middle syllable. Calls have a broad frequency range of 1400–6700kHz. (Figure 5).

Remark. M. acuta sp. nov. is most frequently found on leaves, stems or branches at height of 10–20 cm near the streamlets (SYS a001957, 2266–2269, 2274, 2276 and 2278). However, an adult male individual inspected at night on 20 August 2013, was hidden in soil burrow and called softly. The burrow was located on mud-sandy slopes of the streamlet; the opening of the burrow is small, measuring 10 mm in diameter; posteriorly immediately enlarged a room measuring 100 mm in diameter and 70 mm in depth, connected by two narrow tunnels in opposite directions; 1/3 of the room was filled with water, where the toad was found immersed ( Figure 4 : B, Ba, Bb). When it rained or after raining, they more frequently stayed on dirt roads at a distance of 5–15 m from the stream (SYS a000165, 0 168, 0 169, 0 187, 0 517 and 0521).

Adult males call at night and in the daytime throughout the year. They emit advertisement calls in form of a series of short syllables repeated in slightly quick succession from forest floor, leaves, stems, branches of plants or burrows.

15 specimens were collected in early April, May, June, August, and November, respectively. In addition, we also found several individuals in July and September, including two juveniles (not collected) in July; a few males occasionally emit several short syllables in October. Among them, all adult male individuals were found or collected by their calls, except SYS a000165 and 0 169, collected on dirt roads on 2 May; the male paratype SYS a000165 and 0 169 had fully developed testes in the abdominal cavity, measured 3.0– 3.2 mm in diameter. Specimen SYS a001957, collected on 12 November, also had developed testes; but in the specimens, collected in June and August, testes were atrophied. The gravid female paratypes SYS a000187, 0 168, 0 512 and 0 517, collected from early April to the end of May, with about 30 pure yellowish mature oocytes in each oviduct, measured 1.6 mm in oocyte diameter. Therefore, the breeding season of this species may be from November to early June of the second year.

We dissected SYS a001957, SYS a000169 and SYS a000168, and found four, seven and 24 termites in their stomaches, respectively.

Figures

FIGURE 4. Habitat of M. acuta sp. nov. in the type locality from Heishiding Nature Reserve, Guangdong Province. A: Position of an adult male individual on the stem of a plant, emitting advertisement calls at night. B: Position of an adult male individual hidden in a soil burrow and emitting advertisement calls; Ba: The opening of the burrow is small, measuring 10 mm in diameter; Bb: After opening up the burrow, an enlarged room was revealed in which the male individual was immersed in water. Photos by YLL.

FIGURE 3. A: Dorsolateral view of the adult male holotype SYS a 002267 of Megophrys acuta sp. nov. in life. B: Ventral view of the holotype in life. C and D: Hand and foot of the holotype in life. E: Dorsolateral view of the adult female paratype SYS a 000168 in life; F: Dorsal views of the paratypes SYS a 002274 and 2276 in life. Photos by YYW and YLL.

Tables

TABLE 3. Diagnostic characters separating M. obesa sp. nov. and M. acuta sp. nov. from all known 48 recognized species of Megophrys occurring from the India, Indo-China Peninsula to China. Comparative data were obtained from the literature (Boulenger 1908; Inger & Romer 1961; Taylor 1962; Fei et al. 1992; Tian et al. 2000; Ohler et al. 2002; Mathew & Sen 2007; Fei et al. 2009; Mo et al. 2010; Mahony 2011; Mahony et al. 2011; Wang et al. 2012; Mahony et al. 2013; Wang et al. 2014) and examined specimens of M. boettgeri, M. brachylokos, M. cheni, M. huangshanensis, M. jinggangensis, M. kuatunensis, M. lini, M. mangshanensis, M. minor, M. omeimontis

acuta	SVL males 27.1–33.0	females 28.1–33.6	Horn-like tubercle at edge of upper eyelid: long point (+++); slightly large (++), small (+), absent or indistinct (‒) ++	Vomerine teeth: present (+), or absent (‒) ‒	Tongue notched (++), feebly notched (+), or not notched (‒) ‒	lateral fringes on toes wide (++), narrow (+), lacking (‒) +	Toes: at least one-fourth webbed (+++), at most one-fourth webbed (++), with rudiment of web (+), or without web (‒) +	Tympanum TYM:EYE 0.57–0.71	TIB:SVL 0.38–0.45
obesa	35.6	37.5–41.2	+	‒	‒	‒	+	0.51–0.66	0.41–0.47
aceras	55.8–62.4	/	+	+	+ or ‒	/	+ or ++	0.50–0.67	0.42–0.46
ancrae	39.1–45.0	48.9	+	+	+	‒	+	0.50–0.63	0.46–0.55
auralensis	76.7	/	+	‒	‒	+	+	0.60	0.51
baolongensis	42.0–45.0	/	+	‒	+	‒	‒	0.41	0.46
binchuanensis	32.0–36.0	40.2–42.5	‒	‒	+ or ‒	++	+	0.33–0.50	0.46–0.48
binlingensis	45.1–51.0	/	‒	‒	+	/	+	0.47–0.52	0.52–0.53
boettgeri	34.5–37.8	39.7–46.8	+	‒	+	++	+	0.40–0.67	0.45–0.49
brachykolos	33.7–39.3	33.9–45.9	+	‒	‒	‒	++	>0.50	0.37–0.42
caudoprocta	81.3	/	++	+	‒	/	+	0.50	0.51
cheni	26.2–29.5	31.8–34.1	+	‒	++	++	+	0.41–0.54	0.50–0.54
damrei	57.1	69.1	‒	+	++	‒	+	0.58	/
daweimontis	34.0–37.0	40.0–46.0	+	+	/	‒	‒	/	0.54
gigantica	80.5–107.0	110.4–115.4	‒	‒	++	++	+	hidden	0.49–0.50
glandulosa	76.0–81.0	77.0–100.0	+	+	+	++	+	0.50	0.54–0.59
huangshanensis	36.0–41.6	44.2	+	‒	+	‒	‒	<0.50	0.42–0.45
jingdongensis	53.0–56.5	63.5	+	+	+	++	+++	/	0.58–0.59
jinggangensis	35.1–36.7	38.4–41.6	++	+	‒	+	++	0.73–0.88	0.47–0.50
kuatunensis	26.2–29.6	37.4	+	‒	+	+	‒	0.44	0.38–0.48
lekaguli	55.6–66.6	71.8–94.0	+	+	‒	‒	+	0.59–0.74	0.44–0.52
lini	34.1–39.7	37.0–39.9	+	‒	‒	++	++	0.40–0.60	0.46–0.53
longipes	47.0	65.0	+	+	+	/	+	0.60–0.67	0.55–0.60

TABLE 4. Measurements (in mm) of the type series of M. acuta sp. nov. and M. obesa sp. nov.. See Material and methods for abbreviations.

	Megophrys acuta sp. nov.	Megophrys obesa sp. nov.
	males (n=10) females (n=4)	male (n=1) females (n=6)
SVL	27.1–33.0 (30.9 ± 1.87) 28.1–33.6 (31.6 ± 2.56)	35.6 37.5–41.2 (38.8 ± 1.62)
HDL	9.2–10.9 (10.2 ± 0.49) 9.5–10.8 (10.2 ± 0.53)	12.6 12.7–14.6 (13.8 ± 0.66)
HDW	9.5–11.2 (10.5 ± 0.49) 9.8–11.2 (10.7 ± 064)	13.8 14.0–15.5 (14.8 ± 0.63)
SNT	3.2–4.5 (4.1 ± 0.38) 3.3–4.2 (3.9 ± 0.44)	4.4 4.2–4.8 (4.5 ± 0.22)
IND	2.9–3.5 (3.3 ± 0.16) 2.9–3.3 (3.2 ± 0.21)	3.9 4.0–4.8 (4.5 ± 0.33)
IOD	2.7–3.5 (3.2 ± 0.25) 2.8–3.2 (3.0 ± 0.16)	3.7 4.0–4.2 (4.1 ± 0.10)
EYE	3.4–3.9 (3.7 ± 0.15) 3.7–4.0 (3.8 ± 0.14)	4.1 4.2–4.9 (4.5 ± 0.24)
TMP	2.2–2.7 (2.5 ± 0.20) 2.1–2.3 (2.2 ± 0.1)	2.7 2.2–2.7 (2.5 ± 0.17)
TEY	1.1–1.6 (1.4 ± 0.15) 1.2–1.5 (1.3 ± 0.15)	2.1 2.3–2.6 (2.5 ± 0.12)
HND	6.9–8.5 (7.7 ± 0.42) 6.9–9.1 (8.1 ± 1.02)	8.2 9.1–9.8 (9.5 ± 0.26)
RAD	7.4–8.4 (8.0 ± 0.39) 7.7–8.4 (8.1 ± 0.32)	8.8 9.6–10.8 (10.3 ± 0.43)
TIB	12.3–13.9 (13.0 ± 0.50) 12.7–14.5 (13.5 ± 0.75)	15.7 15.8–17.6 (16.9 ± 0.72)
FTL	15.7–18.4 (17.6 ± 0.80) 16.8–20.1 (18.5 ± 1.46)	20.9 23.9–25.0 (24.2 ± 0.50)
HDL/SVL	0.32–0.34 (0.33 ± 0.01) 0.31–0.34 (0.33 ± 0.01)	0.35 0.33–0.37 (0.36 ± 0.02)
HDW/SVL	0.33–0.36 (0.34 ± 0.01) 0.33–0.34 (0.33 ± 0.01)	0.39 0.37–0.41 (0.39 ± 0.02)
HDW/HDL	1.01–1.07 (1.03 ± 0.02) 1.03–1.09 (1.05 ± 0.03)	1.10 1.03–1.12 (1.10 ± 0.04)
SNT/HDL	0.35–0.42 (0.40 ± 0.02) 0.35–0.41 (0.38 ± 0.03)	0.35 0.31–0.35 (0.33 ± 0.01)
SNT/SVL	0.12–0.14 (0.13 ± 0.01) 0.12–0.13 (0.13 ± 0.01)	0.12 0.11–0.13 (0.12 ± 0.01)
IND/HDW	0.30–0.32 (0.31 ± 0.01) 0.29–0.30 (0.30 ± 0.01)	0.28 0.29–0.31 (0.30 ± 0.01)
IOD/HDW	0.27–0.33 (0.30 ± 0.02) 0.27–0.29 (0.28 ± 0.01)	0.27 0.27–0.30 (0.28 ± 0.01)
EYE/HDL	0.35–0.38 (0.36 ± 0.01) 0.35–0.39 (0.36 ± 0.02)	0.33 0.31–0.34 (0.33±0.01)
EYE/SVL	0.11–0.13 (0.12 ± 0.01) 0.11–0.13 (0.12 ± 0.01)	0.12 0.11–0.12 (0.12 ± 0.01)
TMP/EYE	0.61–0.71 (0.68 ± 0.04) 0.57–0.58 (0.58 ± 0.01)	0.66 0.51–0.60 (0.55 ± 0.03)
TEY/TMP	0.42–0.64 (0.55 ± 0.08) 0.55–0.71 (0.62 ± 0.08)	0.78 0.88–1.09 (0.99 ± 0.07)
HND/SVL	0.23–0.27 (0.25 ± 0.01) 0.24–0.27 (0.26 ± 0.01)	0.23 0.23–0.26 (0.25 ± 0.01)
RAD/SVL	0.23–0.28 (0.26 ± 0.01) 0.24–0.27 (0.26 ± 0.02)	0.25 0.25–0.28 (0.27 ± 0.01)
TIB/SVL	0.38–0.45 (0.42 ± 0.03) 0.40–0.45 (0.43 ± 0.02)	0.44 0.41–0.47 (0.44 ± 0.03)
FTL/SVL	0.54–0.61 (0.57 ± 0.02) 0.57–0.60 (0.59 ± 0.02)	0.59 0.59–0.66 (0.63 ± 0.03)