SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd01b05bfbbcf9885e7d57f58e4e4e2fb549cb73da283e3c5a70099ef797a737' 
  AND token = 'okb3DNYrcb6OuTsCBvc88LRNWIU4bpnpnuMuHtVLzXg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00093

JSON explain

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