SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '777fffa400a05dbac3d10d18487a237bd9bb98e1fa5207a33e88ac58ce335d58' 
  AND token = 'OiqJc18z212tRweqr1bQ1l3+Qbdg6gR0fFnUJMleLMU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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