SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fb654309dd5ac033dd087bdc8237fe15af1c893478bfe13a3deb6f75dbc4be6' 
  AND token = 'ett7bOd0r6SijPWr8NaC5t6WdNyYKSsz8L1LlnZIRw8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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