SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '652c2b51e98dca6b4517346ab3d3a117a3e2ef4794bed71686eda7de7b548efb' 
  AND token = 'VqkYal1CFHt4eE//1G+xTTgIdUJtq36rAmRDkcMMlew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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