The objectives of this study are: (1) to determine whether cyprinodontiform fishes as a whole form a monophyletic group; (2) determine whether each of the five families is monophyletic; (3) define the main subgroups of cyprinodontiforms, with emphasis on the genera Cyprinodontidae; (4) determine the interrelationships of subgroups; (5) present a comprehensive classification of cyprinodontiforms that reflects interrelationships; and (6) provide a hypothesis for the group distribution. Cyprinodontiformes and adrianichthyoids remained as the only constituents of the order Cyprinodontiformes. (4) determine the interrelationships of subgroups; (5) present a comprehensive classification of cyprinodontiforms that reflects interrelationships; and (6) provide a hypothesis for the group distribution.
I propose that Hubbsichthys be removed from the subfamily and placed in synonymy with the genus Poecilia.
OVERVIEW OF PAST INTERNAL CLASSIFICATIONS OF CYPRINODONTIFORM FISHES
Myers (1931) effectively avoided the problem by returning to the placement of the two genera in monotypic families. The Pantandodontinae was removed from the cyprinodontiforms and placed as a close relative of the adrianichthyoids. Foster believed that the fundulines were most closely related to the Anablepidae (which probably included Jenynsia), which together formed the sister group to the poeciliids.
It is also notable for including the implicit statement of the non-monophyletic nature of the family Cyprinodontidae.
DERIVED CHARACTERS OF CYPRINODONTIFORMS
Within cyprinodontiforms, the first pleural rib is located on the parapophysis of the second vertebra. Therefore, the first rib arising on the parapophysis of the second vertebra is a unique feature of cyprinodontiforms. At the posterior tip of the ascending processes of the premaxillae is a large, free rostral cartilage.
Thus, within the cyprinodontiforms there are three basic forms of upper jaw and jaw suspension.
PHYLOGENETIC ANALYSIS
In the genus Nothobranchius, the cartilage attaches directly to the cartilaginous head of the pharyngobranchial (Fig. 24B). Jenynsia is defined by its unique form of gonopodium (anal rays 3, 6, and 7 are extensive, whereas all other anal rays undergo degeneration; and the gonopodium is scaleless) and development (ovarian flaps enter pharyngeal and oral cavities to provide nourishment). Floridichthys and Cualac have an expanded element in the position of the first pharyngobranchial.
CLASSIFICATION
I therefore propose that the superfamily be raised to an order to be known as Cyprinodontiformes Berg, the well-known and still commonly used term for this group of fishes. To make this classification consistent with that of all members of the series Atherinomorpha, Rosen and Parenti (MS) wrote a new classification of atherinomorph fishes. The relationships of these three groups are expressed in the cladogram as an unresolved trichotomy, so each of the three groups has the same rank.
Similarly, the family Goodeidae has traditionally been restricted to the living forms of the Mexican Plain. However, rather than placing the family Profundulidae in its own superfamily, and similarly all other members of the suborder in another superfamily, I have chosen to use the informal section category for this purpose. So there is no change in the definitions of the higher categories, except where the families contain only one genus, but the reason for this has already been stated.
The names Section 1, Division 1 and Sept 1 would all be modifications of the family names already included in them. Conversely, a "disturbing" change in classification would occur if, for example, the family turned out not to be monophyletic, as in the case of the family Cyprinodontidae, as the group name used at the beginning of this study. A reviser of the subfamily Goodeinae (which contains about 36 species in 16 genera) may wish to represent the interrelationships of the species by redefining the genera in the form of a cladistic classification.
A system of prefixes and suffixes (as in Farris, 1976) could be agreed upon to accomplish precisely this task; however, group names would quickly become impractical and therefore ignored in favor of the existing names. If so, the traditional use of the term Cyprinodontidae would have been retained, and the genus Jomeurus would have moved from the Poeciliidae to that egg-laying family.
KEY TO GENERA AND SUPRAGENERIC CATEGORIES
13D); dermosphenotic small, often without a clear sensory tract (Fig. 17C); bony flange present on the second pharyngobranchial at the joint of the interarcual cartilage (Fig. 6A). Family Profundulidae Profundulus (Highlands of western Central America) 16B Premaxillary ascending processes narrow or absent; rostral cartilage small and discoid or absent; inner arms of maxilla not in direct contact with rostral cartilage; lateral ethmoids without anterior flanges (Fig. 57B); autopterotic fossa not enlarged (Fig. 57B) 17A 17A Inner arms of maxillaries directed anteriorly, often with pronounced hooks (Fig. 34), no dorsal projection directed over the premaxillary ascending processes; maxilla twisted, not straight (fig. 5C) Family Fundulidae 18A 18A Posttemporally bifurcated; intestinal convoluted Plancterus (Central North America) 18B Posttemporal right; bowel straight 19A 19A Second pharyngobranchial with extensive articular surface; epipleural ribs meet thoracic ribs rather than the parapophyses of the abdominal vertebrae Fundulus (North and Central America) 19B Second pharyngobranchial without expansion.
3!% 22A 22A Ascending processes of premaxillary long and thin, not shortened; dorsal processes of maxillaries elongate (Fig. 50) Family Valenciidae Valencia (Spain, Italy and Corfu) 22B Ascending processes of premaxillaries shortened; dorsal processes of maxillaries rounded when present 23A 23A Distal arm of maxilla expanded; anterior arm of parasphenoid spatulate; lateral ethmoids not expanded, dorsal processes lying below frontals; premaxillary ascending processes with distinct lateral indentation (Fig. 35); aupterotic fossa not reduced (Fig. 16); inclinators of anal fin not enlarged (Fig. 72) 24A 24A Dentary not enlarged; no pouch created by scales of females around anus and first pair of anal rays; no pectoral ribs on haemal spines; pectoral girdle low on sides, radials placed ventrally or posteriorly (Fig. 8); pelvic fins not set forward;. Oxyzygonectes (Pacific Coast of Costa Rica) 24B Dentary enlarged (Fig. 38C); sternal rib on first haemal spine; pectoral girdle set high on sides, radials placed dorsally (fig. Dar es Salaam and Madagascar) 3IB Pharyngobranchial teeth unicuspid; no spines present; second pharyngobranchial tooth plate not enlarged; outer pelvic fin rays of males normal; exoccipital condyles present; neural spine on first vertebra.
32B Distal arm of premaxilla straight; teeth extend distally along arm 33A 33A Deep in body; first two branchiostegal rays of males not free of branchiostegal membranes Hypsopanchax (east-central Africa) 33B No deep body; first two branchiostegal rays of males free of branchiostegal membranes (fig. 53) Procatopus (Central Africa) 23B Distal arm of the maxilla not expanded; anterior arm of parasphenoid thin; lateral ethmoids expanded medially, dorsal processes not beneath frontals; weaken premaxillary ascending processes; autopterotic fossa reduced (fig. 57); inclinators of the anal fin enlarged (fig. 73) 34A 34A First two to five middle anal radials missing; Subfamily Empetrichthyinae 36A 36A Outer teeth unicuspid; anal and dorsal fin base fleshy; lower pharyngeal teeth enlarged; gill pullers on first arch 12-13 Empetrichthys (Death Valley System) 36B Outer teeth bicuspid; anal and dorsal fin bases fully scaly; inferior pharyngeal teeth normal; gill rakers on first arch more than 20 Crenichthys (Eastern Nevada) 34B All anal radials present; groove in the dorsal processes of the maxillae, extended medially, almost meeting the midline (fig. 41); tooth plate of fourth pharyngobranchial reduced; distal arm of premaxilla bent (fig. 42) 37A 37A. Supraoccipital crest enlarged (fig. 58); dorsal process of autopalatine elongated; parietals present; biserial outer teeth; second pharyngobranchial not reduced;
Meckel's cartilage expanded posteriorly (fig. 43A); transverse processes of vertebrae reduced and cup-shaped Tribe Orestiini 38A. 38A Medial extension of the dentary (fig. 43A, B); neural spine on first vertebra; supra-occipital excluded from formation of foramen magnum; exoccipital condyles present; pharyngobrachial teeth randomly arranged 39A 39A Urohyal not embedded (fig. 13C); dermo- sphenotic not reduced Aphanius (Mediterranean) 39B Urohyal embedded (fig. 141); dermosphenotic reduced or absent 40A 40A Interhial ossified; body completely scaled; post-temporal with lower limb ossified; vertebrae 27 or less "Aphanius".
SYSTEMATIC ACCOUNTS
Gill rakers on the anterior arm of the first arch: 12, Branchiostegal rays: 6; Scales lateral series: 33-37. DIAGNOSIS: Distinguished from all other cyprinodontiforms by an oblique oral cleft caused by a reduction of the anterior ramus of the alveolar arm of the premaxilla. One dorsal ray articulates with each of the first two dorsal radials; The origin of the dorsal fin is opposite to that of the anal fin.
DIAGNOSIS: Distinguished from all other cyprinodontoids by a large aupterotic fossa and a high number of gill rakers on the anterior arm of the first arch (14–23). DIAGNOSIS: Distinguished from all other members of the suborder Cyprinodontoidei by the anteriorly directed ventral arms of the maxillaries often with pronounced hooks;. DIAGNOSIS: Distinguished from all other members of the family Fundulidae by the derived character of a highly convoluted gut.
DIAGNOSIS: Differs from all other cyprinodontiforms by the enlarged cartilaginous articulation point of the second pharyngobranch. DIAGNOSIS: Differs from all other cyprinodontiforms by the first pleural rib on the parapophysis of the first vertebra instead of the second, and by the pronounced quadrangular body shape. DIAGNOSIS: Differs from all other cyprinodontiforms by the elongated and pointed dorsal process of the maxilla.
DIAGNOSIS: Distinguished from all other fish of the order Cyprinodontiformes by robust epiotic and supraoccipital processes;. REMARKS: The anterior displacement of the pelvic fins has been demonstrated in the genus Procatopus (Trewavas, 1974). ETYMOLOGY: Crenichthys from the Greek cren, meaning spring, and ichthys refers to the spring habitat of the genus.
DIAGNOSIS: Differs from all other cyprinodontiforms by the following derived characters: derived form of appendage.
