SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2e69a43cb4e3cbee02b383eb2599353d03cca02cdfd3a72c4d6e441e4f16ad2' 
  AND token = 'muhxV/ctO+NXaeBdlmD9nmkVFsO3hEzUld5TNqaewEM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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