SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'bd714bd55dd4989d69dbd3dba04e46ab7a3d618abf32df494749f1d41ee94278' 
  AND token = 'M6eXBFuJZDtOsTC5IFZcmXBfNZ5ieFLgoouveaJBjto=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}