SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '358458050c642d16f97c8fa813c9e64aa3dff47411c95ebc08dd0d4c5d88d2db' 
  AND token = '7FwjIiWIGePIp4VM/l75Ts80ZwY9YbF9b0oJ4a3k30o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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