Anm. Naturhist. Mueseum Wien 104 B 5-9 Wien, März 003 Description of Girardinichthys ireneae sp.n. from Zacapu, ALFRED C. RADDA* & MANFRED K. MEYER** * Institut für Virologie, Universität Wien, Kinderspitalgasse 15, A-1095 Vienna (Austria)
Summary After some remarks on systematics and taxonomy of the genera Girardinichthys BLEEKER, 1860 an Hubbsina DE BUEN, 1941 a new species Girardinichthys (Hubbsina) ireneae from Zacapu, Michoacán, Mexiko, is described. Zusammenfassung Nach einigen Anmerkungen zur Systematik und Taxonomie der Gattungen Girardinichthys BLEEKER, 1860 und Hubbsina DE BUEN, 1941 wird eine neue Art, Girardinichthys (Hubbsina) ireneae von Zacapu, Michoacán, Mexiko beschrieben. Resumen Despues de algunas observaciones acerca de la sistematica y taxonomia del genero Girardinichthys BLEEKER, 1860 y Hubbsina DE BUEN, 1941 se puede describir una nueva especie, Girardinichthys (Hubbsina) ireneae de Zacapu, Michoacán, Mexico.
Remarks on Girardinichthys BLEEKER, 1860 an Hubbsina DE BUEN, 1941 Until today two species of the genus Girardinichthys and one species of Hubbsina have been described: Girardinichthys multiradiatus (MEEK, 1904) Hubbsina turneri DE BUEN, 1941 Because of the high similarity of these three species we would therefore strongly suggest to designate Hubbsina as a subgenus of Girardinichtys.
Introduction In February 2001 we made a collection trip to the highlands of Central Mexico in order to collect material of some goodeid species, mainly of the genus Allotoca HUBBS and TURNER, 1937. Our twelve collection sites provided the following species: Neoophorus regalis, Allotoca meeki, Allotoca catarinae, Allotoca dugesii, Ilyodon furcidens and Ilyodon xantusi. Goodea atripinnis, Xenotoca variata, Allotoca sp., Zoogoneticus quitzeoensis and Skiffia lermae were found sympatric and syntopic with a form close to Girardinichthys (Hubbsina) turneri at the Laguna de Zacapu, a pond comprising about 33,5 ha at the northwest end of the town of Zacapu. After examination of our material and two specimens collected by Mr. D. Lambert in 1990 (in the collection of the junior author), we decided to describe this form as a new species.
Material an methods The new species of the genus Girardinichthys is based on 7 specimens caught in the wild and 2 specimens from the collection of M. Meyer. The type specimens will be deposited in the Naturhistorisches Museum Wien an the Museum Senckenberg Frankfurt/Main. 3 specimens were kept alive, in order to produce offspring for further examinations. Comparative material: The types and description of G. (H.) turneri DE BUEN, (1941). Measurements an counts follow standard practice (MILLER 1948). Measurements were made by vernier callipers reading to 0,1 mm. The number of specimens for all counts is equal to 5. The gill-raker count of the first gill arch includes any gill rakers in the angle of the gill arch. The last two rays in the dorsal fin are counted as a single ray. Vertebral count includes the hypural plate as one vertebra. Nomenclature of the sensory canal system of the head follows the standard of GOSLINE (1949), that of the gonopodial system follws ROSEN & BAILEY (1963).
ht = Holotype, pt = Paratype, Sl = Standard length, Pdl = Praedorsal length, Pal = Praeanal length, Pvl = Praeventral length, Bh = Body higth, Hl = Head length, Ed = Eye diametre, Snl = Langth of snouth, D = Dorsal fin rays, A = Anal fin rays, Sql = Scales in a longitudinal row, Vert = Number of vertebra, G.r. = Gill rakers.
Genus Girardinichthys BLEEKER, 1860 Diagnosis: Girardinichthys is characteriszed by the higher number of dorsal rays (18-36) in comparison with all other goodeid genera. The daryotype is 2 n = 48 with subtelotelocentric chromosomes. The lack of sensory pores on the preopercle is considered to be a derived trait of the genus.
Girardinichthys (Hubbsina) ireneae sp.n. Holotype: male (NMW-94578), Sl 22 mm, north end of Laguna de Zacapu Michoacán, Mexico; February 15, 2001, A. C. Radda, Austria an S. M. Calderon, Mexico leg. Paratypes 2 females (NMW-94579) Sl 17 mm; Feb. 14, 2001, A. C. Radda, Austria, an M. K. Meyer, Germany, same locality leg. 2 Paratypes in collection of M. M. from the same locality, collected in July 1990 by D. Lambert, male Sl 29,2 mm, female Sl 31,5 mm. In comparison to G. (H.) turneri the new species is characterized by different data of meristics an morphometrics (Tab. 1 - 3):
Tab. 1: Meristic data of four species of the genus Girardinichthys.
Tab. 2: Morphometric data of types of G. (H.) ireneae sp.n.
Tab. 3: Comparison of the morphometric data of G. (H.) turneri and
While females differ only slightly, the figures of the males are more varied. The picmentation of body and fins is also different in both species. Males of G. (H.) turneri are black in colour of the upper part of the body and in the dorsal; males of G. ireneae sp. n. (as well as females) have numerous dark spots on body an dorsal fin (see Fig. 1). An important feature is the presence of sensory pores on the preopercle (supraorbital section 5-6), which is absent in the three other Girardinichthys species (see FITZSIMONS 1981).
Etymology The new species is named in honor of Mrs. Irene Radda, Vienna, Austria.
Ecology The springfed pond is drained by the Angulo River, about 30-35 km NE of Zacapu, which divides in two streams after 20 km; it forms an exorheic basin. Collections were done on February 14 and 15, 2001. On February 14, air temperature = 21 °C, water temperatur = 17 °C, conductivity = 111 uS and 13° German hardness. In the very densely populated lake the number of specimens of the respective species is very varied: In comparison with G. (H.) ireneae sp.n. and Allotoca sp., we caught almost 10-20 times as many individuals of Zoogoneticus, 10 times as many of Goodea, 5 times as many Skiffia an 2 times as many of Xenotoca. A shortage of food seems to produce dwarf forms of all goodeid species in the pond. The size of adults ist almost half of ther respective counterparts in other habitats.
Acknowledgements We are indebted to Mr. D. Lambert, Lincs, GB, for providing us 2 paratypes of G. (H.) ireneae sp.n. an to Mr. Eduard Pürzl, Vienna, Austria, for providing photographs of the new species.
References
Die Literatur wurde zusammengestellt von Girardinichthys ireneae Radda & Meyer, 2003. Het Aquarium (6): 210-214 A.C. Radda & M.K. Meyer (2003): Description of Girardinichthys ireneae sp.n. from Zacapu, Michoacan, Mexico with remarks on the genera Girardinichthys Bleeker, 1860 and Hubbsina De Buen, 1941. Ann. Naturhist. Mus. Wien |
