SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a44f75476db60af8b8a8e1bcd5f1dd9fca08d3444020dd4ec0c5f8c1ac38c000' 
  AND token = 'Cdfg89RJ53GZTjj2ioVfGAjW+4yX56IUfJevKDkEP+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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