HOESE: GOBIOIDEI 



589 



Table 152. Selected Meristics for Gobioid Families and Subfamilies. 



Group 



Branchi- 



oslegal 



rays 



Dl 



D2 



PI 



P2 



Epurals 



Segmented 

 caudal rays 



Vertebrae 



Rhyacichthyidae 6 



Eleotrididae 6 



Xenisthmidae 6 



Microdesmidae 



Microdesminae 5 



Oxymetopontinae 5 



Gobiidae 



Oxudercinae 5 



Amblyopinae 5 



Sicydiinae 5 



Gobiinae 5 



Kxaemariidae 5 



VII 1,8-9 1,8-9 21-22 1,5 3 17 12+16 = 28 



III-X 1,6-17 1,6-13 13-21 1,5 1-2 15-17 10-18+11-19 = 24-36 



0-VI 0-1,9-32 1,9-25 17-21 0-1.1-5 1-2 15-17 10-18+16-28 = 26-46 



XX-XXVIII 26-66 23-61 10-15 1.2-4 1 15-17 42-76 



VI 1,9-37 1,9-36 15-26 1,4-5 1 17 10-11 + 15-16 = 26 



V-VIII 0-1,10-30 0-1,10-30 10-21 1,5 2 17 10+16 = 26 



VI-VIIl 16-50 0-1,14-50 13-21 1,5 1-2 17 10+16-26 = 26-36 



VI 1,9-11 1,9-11 15-23 1,5 1 17 10+16 = 26 



0-X 0-1,5-19 0-1,5-19 11-25 1,4-5 1-2 13,16-17 10-16+14-21=25-36 



IV-V 13-19 1,11-15 3-10 1,5 1 11 10-14+16-17 = 26-31 



sibranchials 2 and 3 present; pterosphenoid present, corono- 

 meckelian bone present; pterygiophores of two dorsal fins nor- 

 mally continuous, without an intemeural gap. One group 

 (Leplophilypnits and Gohiomorphus and relatives) are special- 

 ized in having an intemeural gap (an intemeural space without 

 a pterygiophore) between the two dorsal fins. Members of the 

 group also have often lost several eleotridid primitive features, 

 such as the mesopterygoid and dorsal postcleithrum. Some are 

 specialized in having an unossified scapula and a single epural. 

 Other eleotridids consistently have 2 epurals and a well ossified 

 scapula. The group includes about 40 genera and the following 

 named taxa: Butinae, Belobranchinae. Gobiomoridae. Hypse- 

 leotrini, Milyeringidae, Ophiocarinae, and Philypni. Whether 

 any of these are recognizable must await further study. 



Xenisthmidae— This coral reef group, restricted to the Indo- 

 Pacific, is treated extensively by Springer (1983) and is distinc- 

 tive in the following specializations: lower lip with a free ventral 

 margin; ascending process of premaxilla absent or rudimentary; 

 rostral ossified and functionally replacing ascending process of 

 premaxilla; first basibranchial ossified; basibranchials 2-4 ab- 

 sent; no pterosphenoid or coronomeckelian bone; intemeural 

 gap present between two dorsal fins. The two genera studied 

 lack the dorsal postcleithrum and the mesopterygoid. The group 

 includes 4 genera. 



Microdesmidae— The group possesses the following primitive 

 features: maxilla more or less L-shaped, with a very short inner 

 process articulating medially with lateral ethmoid; usually sep- 

 arate pelvic fins, without an interspinal membrane. The group 

 is uniquely specialized in having a very long posterior pelvic 

 process. Other specializations include the strongly compressed 

 head and body, with lateral eyes; 5 branchiostegal rays; one 

 epural; dorsal postcleithrum and mesopterygoid absent. Trends 

 in the group include reduction of pelvic rays, the tendency for 

 the scales to become nonimbricate, and the development of a 

 very long-based second dorsal fin. Two subfamilies are recog- 

 nized here, but further studies may show both to be distinct 

 families. 



Microdesminae.— The specializations include: maxilla with a 

 long strut-like anterior projection; body very elongate, with a 

 single dorsal fin attached to or reaching near caudal fin; dentary 



with a long ventral process at anterior tip. The worldwide group 

 includes 5 genera and the following named taxa: Cerdalidae, 

 Gunnellichthyidae, and Paragobioididae. 



Ptereleotrinae. — The specializations include: mouth almost ver- 

 tical; articular process of premaxilla absent or fused with as- 

 cending process; a single pterygiophore precedes the first hemal 

 spine. The worldwide group includes 6 genera (2 undescribed) 

 and the following named taxa: Nemateleotrinae. Pogonoculinae, 

 Oxymetopontinae. In addition both subfamilies of microdes- 

 mids contain several specializations sometimes found in Go- 

 biidae, such as the interlocking of the anterior preopercular 

 process with the dorsal end of the symplectic and the expanded 

 dorsal flange of the sphenotic reaching to the supraoccipital. 



Gobiidae. — In some genera primitive features are found, such 

 as the ventral postcleithrum. 2 epurals, and separate head canals 

 between the eyes. Specializations include: pelvic fins usually 

 connected to form a cup-shaped disc, often separate in coral 

 reef genera, but interspinal membrane usually present; pelvic 

 spine displaced forward and ventrally, not in line with rays; 

 mesopterygoid and dorsal postcleithrum absent; palatine nor- 

 mally T-shaped, but L-shaped in some specialized genera; eth- 

 moid process of palatine extends across front of lateral ethmoid, 

 articulating with proximal base of lateral ethmoid or more com- 

 monly with median ethmoid; maxilla generally without an an- 

 terior process; median ethmoid displaced ventrally; an inter- 

 neural gap present between two dorsal fins (except in Trypauchen 

 and relatives. There may be one or two dorsal fins, and most 

 genera have 17 segmented caudal rays, rarely 13 or 16. Several 

 subfamilies have been recognized. Four are recognized here, but 

 further studies may considerably expand the number. 



Oxudercinae.— Tongue fused to floor of mouth; a single pte- 

 rygiophore precedes first hemal arch; teeth flattened; second 

 dorsal fin usually long based; eyes displaced forward and up- 

 ward; 2 epurals, lateral process of sphenotic large and not in 

 contact with eye. The group occurs in mud and mangrove areas 

 in all tropical areas, except the New World. The group contains 

 about 10 genera and the following named taxa: Apocrypteidae, 

 Boleophthalminae. Periophthalmidae. 



Amblyopinae.— Tongue fused to floor of mouth; 2 or 3 pteryg- 

 iophores precede first hemal spine; a single dorsal fin reaching 



