SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be71cddc29fddc86d51c8d3b05db41b590e5f846e9c52f09bb6a5116cb33044f' 
  AND token = 'RoeRO1TgdjNFr0mDcVPwTqe7hAI59NxTqrHoGGXAiAs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}