SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13967f49527c7885d2ae96a9469d5425eb35b9e13ca4bfbea945327c2b27fbfb' 
  AND token = 'qwt9ZThMTBlW1y04Y2moqwN+kXCaGeWAjUIeRUaKkEc=' 
  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"
    }
  }
}