SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1eb9cecf5d19b632c5ffbb8bffe36c8775203874472d7549d0c7b403cb103044' 
  AND token = 'FC+r/zqQYg815W95sKsyzCRzJZYPh9L8a3ckD2oNMNg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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