Xiphophorus multilineatus (Rauchenberger, Kallman & Morizot 1990)
Etymology:
Xiphophorus: Greek, xiphos = sword + Greek, pherein = to carry
multilineatus: Greek: multi-, many; -lineatus, line; in reference to the prominent vertical bars on the flanks.
First description:
Rauchenberger, Kallman & Morizot 1990
Rauchenberger, M., K. D. Kallman, AND D. C. Morizot (1990) Monophyly and geography of the Rio Panuco basin swordtails (genus Xiphophorus) with descriptions of four new species. American Museum Novitates 2975, 1–41.
Synonyms:
X. nigrensis Rosen, 1979
Common name:
High-Backed Pygmy Swordtail
History:
Collected by K. D. Kallman, D. C. Morizot, V. Borkoski, and G. Peters on February 17th 1979
Group:
Xiphophorus multilineatus is one of nine northern swordtails and belongs to the Pygmaeus clade consisting of consisting of X. pygmaeus, X. nigrensis and X. multilineatus.
Type Locality:
Rio Coy near its confluence with the Rio Tampaon, Rio P’anuco drainage, SLP, Mexico.
Distribution:
Rio Coy system, Rio Panuco drainage, SLP: throughout Rio Coy, Arroyo Tambaque, and Arroyo Oxitipa as far as Octzen.
Habitat:
Found in a fast flowing river with dense aquatic plant growth and overhanging shore vegetation.
Size:
Males: 25mm to 40mm, Females: 40mm
Distinguishing characteristics:
A species with a four known size variations within the male range, the largest variant is the one most often in the hobby. X. multilineatus in its larger form is a small high backed form of swordtail with a medium sized sword of roughly ½ – ¾ total body length.
Colour/Pattern Variability:
Males
There are four size variants ranging from 25mm to 40mm, the larger males develop a high back and vertical barring on the flanks. All males have a body colouring of pale metallic blue and a single bold zigzag midlateral line, (present from birth). A black spot can be found at the base of the pectoral fins on all sizes of male except the smallest size variant. The scales above the lateral have a dark edge giving a net like appearance.
A caudal spot is present but only really prominent on the large males. The caudal fin is edged in black and has is generally clear. The sword length varies according to the size variant, the largest males can have a sword length equal to the body length and the smallest 1-2mm. The sword is distinctly upturned, particularly when small and the colouring does not reach the end of the sword, the sword is edged in black.
The dorsal fin is generally clear, there is a black edge and a black band one third of the way up the fin.
As with all of the Pygmaeus clade a yellow male form can be found, but in X. multilineatus this only exists in the smaller size.
Females
A basic body colour of greyish blue with a single bold zigzag lateral line. The scales above the lateral have a dark edge giving a net like appearance.
The dorsal fin is clear, there is a faint black edge and faint black band one third of the way up the fin.
Behaviour:
A timid species that spends much of its time hidden amongst the foliage.
Husbandry:
A large well planted with filtration, aeration and frequent water changes.
Breeding Notes:
Broods are born on a monthly cycle and number about 5 – 10, 20 being generally the maximum amount, fry are large and normally left alone by the parents.
References:
Rauchenberger, Kallman & Morizot: Monophyly and Geography of the Rio P’anuco Basin Swordtails (Genus Xiphophorus) with descriptions of four new species
Derek and Pat Lambert: Platies and swordtails
