SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c541e13bb6b6eccda7c40ead1957d29f29ce4fc1fbbceb5d41265221672fb0ab' 
  AND token = 'ljmGnKIPSVl8QZzBOXA7kahTYiH78VWHO+ZDZmzQ3Vs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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