Tytthoscincus martae GRISMER, WOOD, QUAH, ANUAR, NGADI, MOHD-IZAM & AHMAD, 2017
Can you confirm these amateur observations of Tytthoscincus martae?
|Higher Taxa||Scincidae, Sphenomorphinae (Sphenomorphini), Scincoidea, Sauria, Squamata (lizards)|
|Common Names||E: Hindu Temple Forest skink|
Malay: Mengkarung hutan kuil hindu
|Synonym||Tytthoscincus martae GRISMER, WOOD, QUAH, ANUAR, NGADI, MOHD-IZAM & AHMAD 2017|
|Distribution||Peninsular Malaysia (Pahang)|
Type locality: Hindu Temple 1.2 km south of the town of Fraser’s Hill on the road to the Gap, Pahang, Peninsular Malaysia (N 03°42.099′, E 101°44.090′; 1078 m in elevation)
|Types||Holotype: LSUHC 12688, Adult male, collected by Evan S. H. Quah, Marta S. Grismer and L. Lee Grismer on 23 March 2016. Paratypes: LSUHC 12517–18 collected on 3 December 2015 and LSUHC 12749 and 12751 collected on 21 June 2016 from the Awana Road, Genting Highlands, Pahang, Peninsular Malaysia (N 3°24.036′, E 101°47.212′; 1052 m in elevation) by Evan S. H. Quah and L. Lee Grismer. ZRC 3.6246 is from the same locality as the holotype and was collected by L. Lee Grismer, Perry L. Wood, Jr. and Timothy M. Youmans on 26 August 2006.|
|Diagnosis||Diagnosis: Tytthoscincus martae sp. nov. can be differentiated from all other species of Tytthoscincus in the montane clade except T. bukitensis by having the combination of 8`1, 9`1 or 10`2 superciliaries; a deep, weakly pigmented tympanum; enlarged pectoral scales; 31–35 midbody scales; 70–74 paravertebral scales; 61–72 ventral scales; keeled, subdigital lamellae; seven subdigital lamellae on the third finger; 12 or 13 subdigital lamellae on the fourth toe; TD/HL = 0.12–0.16; HL/ SVL = 0.18–0.26; AXG/SVL = 0.47–0.55; FL/SVL = 0.21– 0.26; HDL/SVL = 0.33–0.38; and a maximum SVL of 44.0 mm (Table 6). All non-ratiometric characters are scored across all other Tytthoscincus and species of Sphenomorphus suspected of being Tytthoscincus in Grismer et al. (2016a: 237) and Karin et al. (2016: 416).|
Comparisons: Tytthoscincus martae sp. nov. can be differentiated from T. jaripendek sp. nov. and T. kakikecil sp. nov. by having as opposed to lacking a deeply recessed, weakly pigmented tympanic membrane. Tytthoscincus martae sp. nov. differs discretely from T. perhentianensis and T. jaripendek sp. nov. by having 31–35 vs. 28–30 (collectively) midbody scales and 70–74 vs. 63–66 (collectively) paravertebral scales. It is further discretely differentiated from T. jaripendek sp. nov., T. perhentianensis and T. kakikecil sp. nov. by having seven vs. five or six subdigital lamellae on the third toe. It is further discretely differentiated from T. jaripendek sp. nov., T. perhentianensis, T. kakikecil sp. nov., T. temengorensis and T. ishaki by having 12 or 13 vs. 9–11 (collectively) subdigital lamellae on the fourth toes. Tytthoscincus martae sp. nov. also bears statistically significant mean differences of all ten characters in varying combinations across all other species (Table 6). Numeric trends of these characters among species in the montane clade are presented in Figures 4and5.
Although the molecular phylogeny suggests that Tytthoscincus martae sp. nov. is a separate species being that it is not nested within any other species, it cannot be discretely nor statistically (P < 0.05) differentiated morphologically from T. bukitensis and both are sympatric at Fraser’s Hill and syntopic at Awana Road, Genting Highlands. The genetic data infer that the monophyly (exclusivity) of each species is strongly supported (1.00/100 and 1.00/96, respectively; Fig. 2) and they share a modest 5.4–7.4% uncorrected pairwise sequence divergence between them. More importantly, both the BI and ML analyses infer T. martae sp. nov. and T. bukitensis are not sister species – although support for this is moderate (0.89/77) – so this conundrum cannot be solved by considering them conspecific because it would render T. bukitensis paraphyletic. Most notably, however, is that certain individuals from each species are more closely related to conspecifics from the other locality than they are to individuals of the other species found only meters apart at the same locality. For example, T. martae sp. nov. LSUHC 12749 from Awana Road is more closely related to T. martae sp. nov. LSUHC 12688 from Fraser’s Hill, 38 km to the north than it is to T. bukitensis LSUHC 12750 collected within 15 min of T. martae sp. nov. LSUHC 12749 on the same day less than 5 m away in the same pile of leaf-litter (Fig. 2). Complicating this issue is that the molecular evidence demonstrates that the current paratype of T. bukitensis from Fraser’s Hill (ZRC 3.6246) must be considered part of T. martae sp. nov. and is not closely related to the holotype of T. bukitensis from Fraser’s Hill (ZRC 2.6245). Thus, the type series of T. bukitensis is composed of two different species that are not each other’s closest relatives. Therefore, ZRC 3.6246 is removed here from the type series of T. bukitensis and transferred to the species T. martae sp. nov.
If T. bukitensis and T. martae sp. nov. were reciprocally monophyletic and occurred exclusively at different localities (i.e. they were not sympatric), we would not recognize them as separate species and posit that their genetic distinction represents isolation by distance and individuals from the intervening regions would need to be examined and sequenced. Such is the case with the allopatric sister species Hemiphyllodactylus titiwangsaensis and H. cf. titiwangsaensis – from the same mountain range as T. bukitensis and T. martae sp. nov. – that are morphologically indistinguishable yet have an uncorrected pairwise sequence divergence between them of 12.8% (Cobos et al., 2016). However, T. bukitensis and T. martae sp. nov. are not sister species and individuals of each occur at both localities and are even syntopic at one – strongly suggesting they are separate, highly convergent, genetically exclusive lineages.
Tytthoscincus martae sp. nov. and T. bukitensis are differentiated in their 50% combined upper and lower quartile ranges of midbody scales that only narrowly approach one another at 32.9 (Fig. 5). Although the mean values of their respective counts are not statistically significantly different, this is due to a high outlying value of 35 for midbody scales in T. bukitensis (LSUHC 12750). Given that these two species are syntopic in at least one part of their range and the only way to unequivocally separate them is with a molecular analysis, we consider them cryptic species (see below). We are well aware of the potential pitfalls using a single mitochondrial marker in cases such as these and that the use of nuclear markers might resolve the issue of potential conspecificity. However, genomic data would be the best way to test these hypotheses and plans are in progress to do so.
|Comment||Habitat: Tytthoscincus martae sp. nov. inhabits leaf-litter in hill dipterocarp forests from at least 991–1239 m in elevation (Fig. 14). Specimens from Awana Road, Genting Highlands were collected by raking leaves that had accumulated at the foot of an earthen bank and by turning logs and rocks buried in leaf-litter. Lizards were most commonly found in areas where moisture from the hillside had seeped down to the edge of the road. During overcast days, lizards were seen running swiftly through small rocks and root tan- gles on the forest floor beneath the canopy in the nearby forest. However, we do not know if these specimens were T. martae sp. nov. or T. bukitensis. At Fraser’s Hill, specimens were found along the edges of seeps or small streams in damp microhabitats. ZRC 3.6246 was found beneath a log and LSUHC 12688 was found buried in the leaf-litter, both near the edges of small drainages.|
|Etymology||The specific epithet martae is a matronym honouring Lee Grismer’s wife Marta S. Grismer “for her long, non-wavering commitment and support of my work for many years, her efforts in the field on many trips across Southeast Asia and Latin America and for generating the morphological data sets for a number of our studies.”|