SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4cdcbfbaab55d4de8e9c56e9a75ab2ed27d36d1ad29f1bae585b1d69a6167504' 
  AND token = 'bYwYQdNXlX7x+f9Vjv/PfOfSGGEFdpt4DGyto4xtXmU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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