SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8334579e774d62af65ed2bd16a8b1431a9c60d47aa5aa6c4b542059236ca81b7' 
  AND token = 'fr40/x0cHD6CA1pKNbI7LMQ7vk7dBuqOkzBaEOfHsPo=' 
  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"
    }
  }
}