SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c77e248c9b655575704d286806d8b05e1470ab0adc2397f7fe379c6d9f483cb' 
  AND token = '5W0sN6IXK5B+sYAAGwEA2vpzWfiFgugDrgrHoDLD//M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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