Table 3. Comparison of the number of chromosomes, number of chiasmata per meiotic cell, and expected and observed map lengths in ambystomatid and salamandrid salamanders.

				Expected Map Length (cM) Based on
Species	No. of Chr	No. of Arms	No. of Chias	No. of Arms	No. of Chias	Observed Map Length (cM)
Ambystomatidae
Ambystoma macrodactylum	14	28a	53a	1400	2650	NA
Ambystoma mexicanumb	14	28	113	1400	5650	4200c
Salamandridae
Ichthyosaura alpestris	12	24d	32.3e	1200	1615	NA
Lissotriton boscai	12	24d	21.7e	1200	1085	NA
Lissotriton helveticus	12	24d	22.2e	1200	1110	NA
Lissotriton montandoni	12	24d	23.3f	1200	1165	1484g
Lissotriton vulgaris	12	24d	24.2h	1200	1210
Notophthalmus viridescens	11	22d	NA	1100	NA	6162i
Pleurodeles waltl	12	24d	28.1j	1200	1405	NA
Salamandra salamandra	12	24d	36.8k	1200	1840	NA
Triturus carnifex	12	24d	31.4l	1200	1570	NA
Triturus cristatus	12	24d	37.4l	1200	1870	NA
Triturus karelinii	12	24d	40.8l	1200	2040	NA
Triturus marmoratus	12	24d	25.7e	1200	1285	NA

Expected map length based on the number of chromosomal arms assumes a single crossover per arm. No. of chr, haploid number of chromosomes; No. of arms, number of chromosomal arms; No. of chias, average number of chiasmata per meiotic cell; NA, not available.

^aKezer et al. (1980).

^bCallan (1966); Smith et al. (2005).

^cVoss et al. (2011).

^dAll salamandrids are characterized by biarmed chromosomes (Sessions 2008).

^eHerrero and López-Fernández (1986).

^fZbożeń and Rafiński (1993); Zbożeń (1997).

^gThis study.

^hL. vulgaris meridionalis (Barsacchi et al. 1970).

ⁱKeinath et al. (2016).

^jWickbom (1945).

^kMancino et al. (1969).

^lCallan and Spurway (1951).