SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93a74be4acbc19c2a215325450c99f51809ce725b64e8e353ae1b4bc16f73ed2' 
  AND token = 'XRtk4YfjLRogkkWM3wgKAL0HgAs0pbpzE+dKqOC3ba0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}