SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4bd917f66541edfc10c47565ce02a1b6da70f85f6dfcc9f89c57d5f4ea42fa1' 
  AND token = 'XPUJzqrQnhNlexffQop12EVDx1jdSD/ZUa6cF9vy2Os=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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