SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a14c6824585a3e1850542bab00cd2b3ca1038e820725ef808250a5001f46b93' 
  AND token = 'cpTyzoge6BmKHml18mv8CADJIGsjTM1zMgr0ATqQWnU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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